Other: Bridge James 1.8.3

- [x] write tests to check that IMAP and SMTP servers are closed when there
  is no internet
- [x] always create new go-smtp instance during listenAndServe(int)

.golangci.yml

@@ -1,3 +1,4 @@
+---
 run:
   timeout: 10m
   build-tags:
@@ -8,9 +9,11 @@ run:
 issues:
   exclude-use-default: false
   exclude:
-     - Using the variable on range scope `tt` in function literal
+    - Using the variable on range scope `tt` in function literal
-     - should have comment (\([^)]+\) )?or be unexported # For now we are missing a lot of comments.
+    # For now we are missing a lot of comments.
-     - at least one file in a package should have a package comment # For now we are missing a lot of comments.
+    - should have comment (\([^)]+\) )?or be unexported
+    # For now we are missing a lot of comments.
+    - at least one file in a package should have a package comment
 
   exclude-rules:
     - path: _test\.go
@@ -30,7 +33,7 @@ linters-settings:
 linters:
   # setting disable-all will make only explicitly enabled linters run
   disable-all: true
-  
+
   enable:
     - deadcode          # Finds unused code [fast: true, auto-fix: false]
     - errcheck          # Errcheck is a program for checking for unchecked errors in go programs. These unchecked errors can be critical bugs in some cases [fast: true, auto-fix: false]
@@ -49,7 +52,6 @@ linters:
     - funlen            # Tool for detection of long functions [fast: true, auto-fix: false]
     - gochecknoglobals  # Checks that no globals are present in Go code [fast: true, auto-fix: false]
     - gochecknoinits    # Checks that no init functions are present in Go code [fast: true, auto-fix: false]
-    #- gocognit          # Computes and checks the cognitive complexity of functions [fast: true, auto-fix: false]
     - goconst           # Finds repeated strings that could be replaced by a constant [fast: true, auto-fix: false]
     - gocritic          # The most opinionated Go source code linter [fast: true, auto-fix: false]
     - gocyclo           # Computes and checks the cyclomatic complexity of functions [fast: true, auto-fix: false]
@@ -58,15 +60,52 @@ linters:
     - goimports         # Goimports does everything that gofmt does. Additionally it checks unused imports [fast: true, auto-fix: true]
     - golint            # Golint differs from gofmt. Gofmt reformats Go source code, whereas golint prints out style mistakes [fast: true, auto-fix: false]
     - gosec             # Inspects source code for security problems [fast: true, auto-fix: false]
-    - interfacer        # Linter that suggests narrower interface types [fast: true, auto-fix: false]
-    - maligned          # Tool to detect Go structs that would take less memory if their fields were sorted [fast: true, auto-fix: false]
     - misspell          # Finds commonly misspelled English words in comments [fast: true, auto-fix: true]
     - nakedret          # Finds naked returns in functions greater than a specified function length [fast: true, auto-fix: false]
     - prealloc          # Finds slice declarations that could potentially be preallocated [fast: true, auto-fix: false]
-    - scopelint         # Scopelint checks for unpinned variables in go programs [fast: true, auto-fix: false]
     - stylecheck        # Stylecheck is a replacement for golint [fast: true, auto-fix: false]
     - unconvert         # Remove unnecessary type conversions [fast: true, auto-fix: false]
     - unparam           # Reports unused function parameters [fast: true, auto-fix: false]
     - whitespace        # Tool for detection of leading and trailing whitespace [fast: true, auto-fix: true]
-    #- wsl               # Whitespace Linter - Forces you to use empty lines! [fast: true, auto-fix: false]
+    - asciicheck        # Simple linter to check that your code does not contain non-ASCII identifiers [fast: true, auto-fix: false]
-    #- lll               # Reports long lines [fast: true, auto-fix: false]
+    - durationcheck     # check for two durations multiplied together [fast: false, auto-fix: false]
+    - exhaustive        # check exhaustiveness of enum switch statements [fast: false, auto-fix: false]
+    - exportloopref     # checks for pointers to enclosing loop variables [fast: false, auto-fix: false]
+    - forcetypeassert   # finds forced type assertions [fast: true, auto-fix: false]
+    - godot             # Check if comments end in a period [fast: true, auto-fix: true]
+    - goheader          # Checks is file header matches to pattern [fast: true, auto-fix: false]
+    - gomodguard        # Allow and block list linter for direct Go module dependencies. This is different from depguard where there are different block types for example version constraints and module recommendations. [fast: true, auto-fix: false]
+    - goprintffuncname  # Checks that printf-like functions are named with `f` at the end [fast: true, auto-fix: false]
+    - importas          # Enforces consistent import aliases [fast: false, auto-fix: false]
+    - makezero          # Finds slice declarations with non-zero initial length [fast: false, auto-fix: false]
+    - nilerr            # Finds the code that returns nil even if it checks that the error is not nil. [fast: false, auto-fix: false]
+    - predeclared       # find code that shadows one of Go's predeclared identifiers [fast: true, auto-fix: false]
+    - revive            # Fast, configurable, extensible, flexible, and beautiful linter for Go. Drop-in replacement of golint. [fast: false, auto-fix: false]
+    - rowserrcheck      # checks whether Err of rows is checked successfully [fast: false, auto-fix: false]
+    - sqlclosecheck     # Checks that sql.Rows and sql.Stmt are closed. [fast: false, auto-fix: false]
+    - tparallel         # tparallel detects inappropriate usage of t.Parallel() method in your Go test codes [fast: false, auto-fix: false]
+    - wastedassign      # wastedassign finds wasted assignment statements. [fast: false, auto-fix: false]
+    # - wsl               # Whitespace Linter - Forces you to use empty lines! [fast: true, auto-fix: false]
+    # - lll               # Reports long lines [fast: true, auto-fix: false]
+    # Consider to include:
+    # - gocognit          # Computes and checks the cognitive complexity of functions [fast: true, auto-fix: false]
+    # - cyclop            # checks function and package cyclomatic complexity [fast: false, auto-fix: false]
+    # - errorlint         # go-errorlint is a source code linter for Go software that can be used to find code that will cause problems with the error wrapping scheme introduced in Go 1.13. [fast: false, auto-fix: false]
+    # - exhaustivestruct  # Checks if all struct's fields are initialized [fast: false, auto-fix: false]
+    # - forbidigo         # Forbids identifiers [fast: true, auto-fix: false]
+    # - gci               # Gci control golang package import order and make it always deterministic. [fast: true, auto-fix: true]
+    # - gocognit          # Computes and checks the cognitive complexity of functions [fast: true, auto-fix: false]
+    # - goerr113          # Golang linter to check the errors handling expressions [fast: false, auto-fix: false]
+    # - gofumpt           # Gofumpt checks whether code was gofumpt-ed. [fast: true, auto-fix: true]
+    # - gomnd             # An analyzer to detect magic numbers. [fast: true, auto-fix: false]
+    # - gomoddirectives   # Manage the use of 'replace', 'retract', and 'excludes' directives in go.mod. [fast: true, auto-fix: false]
+    # - ifshort           # Checks that your code uses short syntax for if-statements whenever possible [fast: true, auto-fix: false]
+    # - nestif            # Reports deeply nested if statements [fast: true, auto-fix: false]
+    # - nlreturn          # nlreturn checks for a new line before return and branch statements to increase code clarity [fast: true, auto-fix: false]
+    # - noctx             # noctx finds sending http request without context.Context [fast: false, auto-fix: false]
+    # - nolintlint        # Reports ill-formed or insufficient nolint directives [fast: true, auto-fix: false]
+    # - paralleltest      # paralleltest detects missing usage of t.Parallel() method in your Go test [fast: true, auto-fix: false]
+    # - testpackage       # linter that makes you use a separate _test package [fast: true, auto-fix: false]
+    # - thelper           # thelper detects golang test helpers without t.Helper() call and checks the consistency of test helpers [fast: false, auto-fix: false]
+    # - wrapcheck         # Checks that errors returned from external packages are wrapped [fast: false, auto-fix: false]
+

Changelog.md

@@ -2,6 +2,129 @@
 
 Changelog [format](http://keepachangelog.com/en/1.0.0/)
 
+## [Bridge 1.8.3] James
+
+### Fixed
+* GODT-1182: Use correct contact route.
+
+
+## [Bridge 1.8.2] James
+
+### Fixed
+* GODT-1175: Bug reporting.
+
+
+## [Bridge 1.8.1] James
+
+### Fixed
+* GODT-1165: Handle UID FETCH with sequence range of empty mailbox.
+
+
+## [Bridge 1.8.0] James
+
+### Added
+* GODT-1056 Check encrypted size of the message before upload.
+* GODT-1143 Turn off SMTP server while no connection.
+* GODT-1089 Explicitly open system preferences window on BigSur.
+
+### Fixed
+* GODT-1159 SMTP server not restarting after restored internet.
+* GODT-1146 Refactor handling of fetching BODY[HEADER] (and similar) regarding trailing newline.
+* GODT-1152 Correctly resolve wildcard sequence/UID set.
+* Other: Avoid API jail.
+
+
+## [Bridge 1.7.1] Iron
+
+### Fixed
+* GODT-1081 Properly return newlines when returning headers.
+* GODT-1150 Externally encrypted messages with missing private key would not be built with custom message.
+* GODT-1141 Attachment is named as attachment.bin in some cases.
+
+
+## [Bridge 1.7.0] Iron
+
+### Added
+* GODT-213 New message builder:
+* Preserve Content-Type for undecryptable message body.
+* Use application/octet-stream for encrypted parts.
+* Force no transfer encoding for embedded message/rfc822 parts.
+* Remove dead code GetRelatedHeader/GetRelatedBoundary.
+* Correctly expect text/plain in custom message text parts.
+* Force text/plain for custom message text part.
+* Complex external encrypted tests (multipart/alternative, message/rfc822 attachment).
+
+### Fixed
+* GODT-1136 DB Cache header from builder and test.
+* GODT-1113 Fix tray icon size on macOS Big Sur.
+* GODT-947 Force colors in logs.
+
+
+## [Bridge 1.6.9] HZM
+
+### Fixed
+* GODT-1121 'Keep the application up to date' switches off after restarting Bridge.
+
+
+## [Bridge 1.6.8] HZM
+
+### Fixed
+* GODT-1120 Use Info level in internal/app logs.
+
+
+## [IE 1.3.3] Farg
+
+### Fixed
+* GODT-1120 Use Info level in internal/app logs.
+
+
+## [Bridge 1.6.7] HZM
+
+### Added
+* GODT-1111 Add correct metadata to Windows executables.
+* GODT-1112 Add application to Windows Firewall exclusion list on install.
+* GODT-1077 Track how many times message is built to help understand re-syncs.
+
+### Changed
+* GODT-247 Revise all storage locations (cache, config, local etc).
+
+### Fixed
+* GODT-948 Parser does not handle embedding of Content-Type: message/rfc822.
+* GODT-1079 Correct 9001 error handling on login.
+
+### Security
+* GODT-1105 Dylib Hijacking security fix.
+
+
+## [IE 1.3.2] Farg
+
+### Added
+* GODT-1111 Add correct metadata to Windows executables.
+* GODT-1112 Add application to Windows Firewall exclusion list on install.
+
+### Changed
+* GODT-247 Revise all storage locations (cache, config, local etc).
+
+### Fixed
+* GODT-1079 Correct 9001 error handling on login.
+
+### Security
+* GODT-1105 Dylib Hijacking security fix.
+
+
+## [IE 1.3.1] Farg
+
+### Changed
+* GODT-1047 No silent updates for Import-Export app.
+* GODT-247 Cache and update files moved from user's cache to config.
+
+### Fixed
+* Other: include latest go.mod/go.sum changes.
+* GODT-803 Fix import to wrong target address.
+* GODT-948 Embedded messages.
+* GODT-1043 Fix showing long login error in GUI dialog.
+
+
 ## [Bridge 1.6.6] HZM
 
 ### Added

Makefile

@@ -10,8 +10,8 @@ TARGET_OS?=${GOOS}
 .PHONY: build build-ie build-nogui build-ie-nogui build-launcher build-launcher-ie  versioner hasher
 
 # Keep version hardcoded so app build works also without Git repository.
-BRIDGE_APP_VERSION?=1.6.6+git
+BRIDGE_APP_VERSION?=1.8.3+git
-IE_APP_VERSION?=1.3.0+git
+IE_APP_VERSION?=1.3.3+git
 APP_VERSION:=${BRIDGE_APP_VERSION}
 SRC_ICO:=logo.ico
 SRC_ICNS:=Bridge.icns
@@ -19,6 +19,7 @@ SRC_SVG:=logo.svg
 TGT_ICNS:=Bridge.icns
 EXE_NAME:=proton-bridge
 CONFIGNAME:=bridge
+WINDRES_DEFINE:=BUILD_BRIDGE
 ifeq "${TARGET_CMD}" "Import-Export"
     APP_VERSION:=${IE_APP_VERSION}
     SRC_ICO:=ie.ico
@@ -27,6 +28,7 @@ ifeq "${TARGET_CMD}" "Import-Export"
     TGT_ICNS:=ImportExport.icns
     EXE_NAME:=proton-ie
     CONFIGNAME:=importExport
+	WINDRES_DEFINE:=BUILD_IE
 endif
 REVISION:=$(shell git rev-parse --short=10 HEAD)
 BUILD_TIME:=$(shell date +%FT%T%z)
@@ -56,7 +58,7 @@ EXE_QT:=${DIRNAME}
 ifeq "${TARGET_OS}" "windows"
     EXE:=${EXE}.exe
     EXE_QT:=${EXE_QT}.exe
-    ICO_FILES:=${SRC_ICO} icon.rc icon_windows.syso
+    RESOURCE_FILE:=resource.syso
 endif
 ifeq "${TARGET_OS}" "darwin"
     DARWINAPP_CONTENTS:=${DEPLOY_DIR}/darwin/${EXE}.app/Contents
@@ -89,8 +91,14 @@ build-nogui: gofiles
 build-ie-nogui:
 	TARGET_CMD=Import-Export $(MAKE) build-nogui
 
-build-launcher:
+ifeq "${GOOS}" "windows"
-	go build ${BUILD_FLAGS_LAUNCHER} -o launcher-${APP} cmd/launcher/main.go
+  	PRERESOURCECMD:=cp ./resource.syso ./cmd/launcher/resource.syso
+	POSTRESOURCECMD:=rm -f ./cmd/launcher/resource.syso
+endif
+build-launcher: ${RESOURCE_FILE}
+	${PRERESOURCECMD}
+	go build ${BUILD_FLAGS_LAUNCHER} -o launcher-${EXE} ./cmd/launcher/
+	${POSTRESOURCECMD}
 
 build-launcher-ie:
 	TARGET_CMD=Import-Export $(MAKE) build-launcher
@@ -134,7 +142,7 @@ ifneq "${GOOS}" "${TARGET_OS}"
   endif
 endif
 
-${EXE_TARGET}: check-has-go gofiles ${ICO_FILES} ${VENDOR_TARGET}
+${EXE_TARGET}: check-has-go gofiles ${RESOURCE_FILE} ${VENDOR_TARGET}
 	rm -rf deploy ${TARGET_OS} ${DEPLOY_DIR}
 	cp cmd/${TARGET_CMD}/main.go .
 	qtdeploy ${BUILD_FLAGS_GUI} ${QT_BUILD_TARGET}
@@ -142,13 +150,12 @@ ${EXE_TARGET}: check-has-go gofiles ${ICO_FILES} ${VENDOR_TARGET}
 	if [ "${EXE_QT_TARGET}" != "${EXE_TARGET}" ]; then mv ${EXE_QT_TARGET} ${EXE_TARGET}; fi
 	rm -rf ${TARGET_OS} main.go
 
-logo.ico ie.ico: ./internal/frontend/share/icons/${SRC_ICO}
-	cp $^ $@
-icon.rc: ./internal/frontend/share/icon.rc
-	cp $^ .
-icon_windows.syso: icon.rc logo.ico
-	windres --target=pe-x86-64 -o $@ $<
 
+WINDRES_YEAR:=$(shell date +%Y)
+APP_VERSION_COMMA:=$(shell echo "${APP_VERSION}" | sed -e 's/[^0-9,.]*//g' -e 's/\./,/g')
+resource.syso: ./internal/frontend/share/info.rc ./internal/frontend/share/icons/${SRC_ICO} .FORCE
+	rm -f ./*.syso
+	windres --target=pe-x86-64 -I ./internal/frontend/share/icons/ -D ${WINDRES_DEFINE} -D ICO_FILE=${SRC_ICO} -D EXE_NAME="${EXE_NAME}" -D FILE_VERSION="${APP_VERSION}" -D ORIGINAL_FILE_NAME="${EXE}" -D PRODUCT_VERSION="${APP_VERSION}" -D FILE_VERSION_COMMA=${APP_VERSION_COMMA} -D YEAR=${WINDRES_YEAR} -o $@ $<
 
 ## Rules for therecipe/qt
 .PHONY: prepare-vendor update-vendor update-qt-docs
@@ -158,6 +165,7 @@ THERECIPE_ENV:=github.com/therecipe/env_${TARGET_OS}_amd64_513
 # therecipe/env in order to download it only once
 vendor-cache/${THERECIPE_ENV}:
 	git clone https://${THERECIPE_ENV}.git vendor-cache/${THERECIPE_ENV}
+	if [ "${TARGET_OS}" == "darwin" ]; then cp -f "./utils/QTBUG-88600/libqcocoa.dylib" "./vendor-cache/${THERECIPE_ENV}/5.13.0/clang_64/plugins/platforms/"; fi;
 
 # The command used to make symlinks is different on windows.
 # So if the GOOS is windows and we aren't crossbuilding (in which case the host os would still be *nix)
@@ -181,7 +189,7 @@ update-qt-docs:
 
 ## Dev dependencies
 .PHONY: install-devel-tools install-linter install-go-mod-outdated install-git-hooks
-LINTVER:="v1.29.0"
+LINTVER:="v1.39.0"
 LINTSRC:="https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh"
 
 install-dev-dependencies: install-devel-tools install-linter install-go-mod-outdated
@@ -245,12 +253,17 @@ bench:
 coverage: test
 	go tool cover -html=/tmp/coverage.out -o=coverage.html
 
+integration-test-bridge:
+	${MAKE} -C test test-bridge
+
 mocks:
-	mockgen --package mocks github.com/ProtonMail/proton-bridge/internal/users Locator,PanicHandler,ClientManager,CredentialsStorer,StoreMaker > internal/users/mocks/mocks.go
+	mockgen --package mocks github.com/ProtonMail/proton-bridge/internal/users Locator,PanicHandler,CredentialsStorer,StoreMaker > internal/users/mocks/mocks.go
-	mockgen --package mocks github.com/ProtonMail/proton-bridge/internal/transfer PanicHandler,ClientManager,IMAPClientProvider > internal/transfer/mocks/mocks.go
+	mockgen --package mocks github.com/ProtonMail/proton-bridge/pkg/listener Listener > internal/users/mocks/listener_mocks.go
-	mockgen --package mocks github.com/ProtonMail/proton-bridge/internal/store PanicHandler,ClientManager,BridgeUser,ChangeNotifier > internal/store/mocks/mocks.go
+	mockgen --package mocks github.com/ProtonMail/proton-bridge/internal/transfer PanicHandler,IMAPClientProvider > internal/transfer/mocks/mocks.go
+	mockgen --package mocks github.com/ProtonMail/proton-bridge/internal/store PanicHandler,BridgeUser,ChangeNotifier > internal/store/mocks/mocks.go
 	mockgen --package mocks github.com/ProtonMail/proton-bridge/pkg/listener Listener > internal/store/mocks/utils_mocks.go
-	mockgen --package mocks github.com/ProtonMail/proton-bridge/pkg/pmapi Client > pkg/pmapi/mocks/mocks.go
+	mockgen --package mocks github.com/ProtonMail/proton-bridge/pkg/pmapi Client,Manager > pkg/pmapi/mocks/mocks.go
+	mockgen --package mocks github.com/ProtonMail/proton-bridge/pkg/message Fetcher > pkg/message/mocks/mocks.go
 
 lint: gofiles lint-golang lint-license lint-changelog
 
@@ -294,6 +307,7 @@ LOG?=debug
 LOG_IMAP?=client # client/server/all, or empty to turn it off
 LOG_SMTP?=--log-smtp # empty to turn it off
 RUN_FLAGS?=-m -l=${LOG} --log-imap=${LOG_IMAP} ${LOG_SMTP}
+RUN_FLAGS_IE?=-m -l=${LOG}
 
 run: run-nogui-cli
 
@@ -316,11 +330,11 @@ run-ie-qml-preview:
 	$(MAKE) -C internal/frontend/qt-ie -f Makefile.local qmlpreview
 
 run-ie:
-	TARGET_CMD=Import-Export $(MAKE) run
+	TARGET_CMD=Import-Export RUN_FLAGS="${RUN_FLAGS_IE}" $(MAKE) run
 run-ie-qt:
-	TARGET_CMD=Import-Export $(MAKE) run-qt
+	TARGET_CMD=Import-Export RUN_FLAGS="${RUN_FLAGS_IE}" $(MAKE) run-qt
 run-ie-nogui:
-	TARGET_CMD=Import-Export $(MAKE) run-nogui
+	TARGET_CMD=Import-Export RUN_FLAGS="${RUN_FLAGS_IE}" $(MAKE) run-nogui
 
 clean-frontend-qt:
 	$(MAKE) -C internal/frontend/qt -f Makefile.local clean
@@ -337,7 +351,7 @@ clean: clean-vendor
 	rm -rf cmd/Desktop-Bridge/deploy
 	rm -rf cmd/Import-Export/deploy
 	rm -f build last.log mem.pprof main.go
-	rm -rf logo.ico icon.rc icon_windows.syso internal/frontend/qt/icon_windows.syso
+	rm -f resource.syso
 	rm -f release-notes/bridge.html
 	rm -f release-notes/import-export.html
 
@@ -345,3 +359,5 @@ clean: clean-vendor
 generate:
 	go generate ./...
 	$(MAKE) add-license
+
+.FORCE:

go.mod

@@ -40,7 +40,7 @@ require (
 	github.com/fatih/color v1.9.0
 	github.com/flynn-archive/go-shlex v0.0.0-20150515145356-3f9db97f8568 // indirect
 	github.com/getsentry/sentry-go v0.8.0
-	github.com/go-resty/resty/v2 v2.3.0
+	github.com/go-resty/resty/v2 v2.6.0
 	github.com/golang/mock v1.4.4
 	github.com/google/go-cmp v0.5.1
 	github.com/google/uuid v1.1.1
@@ -50,20 +50,21 @@ require (
 	github.com/keybase/go-keychain v0.0.0-20200502122510-cda31fe0c86d
 	github.com/logrusorgru/aurora v2.0.3+incompatible
 	github.com/mattn/go-runewidth v0.0.9 // indirect
-	github.com/miekg/dns v1.1.30
+	github.com/miekg/dns v1.1.41
 	github.com/nsf/jsondiff v0.0.0-20200515183724-f29ed568f4ce
 	github.com/olekukonko/tablewriter v0.0.4 // indirect
 	github.com/pkg/errors v0.9.1
-	github.com/pkg/math v0.0.0-20141027224758-f2ed9e40e245
 	github.com/sirupsen/logrus v1.7.0
 	github.com/skratchdot/open-golang v0.0.0-20200116055534-eef842397966
 	github.com/ssor/bom v0.0.0-20170718123548-6386211fdfcf // indirect
 	github.com/stretchr/testify v1.6.1
 	github.com/therecipe/qt v0.0.0-20200701200531-7f61353ee73e
+	github.com/therecipe/qt/internal/binding/files/docs/5.12.0 v0.0.0-20200904063919-c0c124a5770d // indirect
+	github.com/therecipe/qt/internal/binding/files/docs/5.13.0 v0.0.0-20200904063919-c0c124a5770d // indirect
 	github.com/urfave/cli/v2 v2.2.0
 	github.com/vmihailenco/msgpack/v5 v5.1.3
 	go.etcd.io/bbolt v1.3.5
-	golang.org/x/net v0.0.0-20200707034311-ab3426394381
+	golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4
 	golang.org/x/text v0.3.5-0.20201125200606-c27b9fd57aec
 )
 

go.sum

@@ -113,8 +113,8 @@ github.com/go-check/check v0.0.0-20180628173108-788fd7840127/go.mod h1:9ES+weclK
 github.com/go-errors/errors v1.0.1 h1:LUHzmkK3GUKUrL/1gfBUxAHzcev3apQlezX/+O7ma6w=
 github.com/go-errors/errors v1.0.1/go.mod h1:f4zRHt4oKfwPJE5k8C9vpYG+aDHdBFUsgrm6/TyX73Q=
 github.com/go-martini/martini v0.0.0-20170121215854-22fa46961aab/go.mod h1:/P9AEU963A2AYjv4d1V5eVL1CQbEJq6aCNHDDjibzu8=
-github.com/go-resty/resty/v2 v2.3.0 h1:JOOeAvjSlapTT92p8xiS19Zxev1neGikoHsXJeOq8So=
+github.com/go-resty/resty/v2 v2.6.0 h1:joIR5PNLM2EFqqESUjCMGXrWmXNHEU9CEiK813oKYS4=
-github.com/go-resty/resty/v2 v2.3.0/go.mod h1:UpN9CgLZNsv4e9XG50UU8xdI0F43UQ4HmxLBDwaroHU=
+github.com/go-resty/resty/v2 v2.6.0/go.mod h1:PwvJS6hvaPkjtjNg9ph+VrSD92bi5Zq73w/BIH7cC3Q=
 github.com/gobwas/httphead v0.0.0-20180130184737-2c6c146eadee/go.mod h1:L0fX3K22YWvt/FAX9NnzrNzcI4wNYi9Yku4O0LKYflo=
 github.com/gobwas/pool v0.2.0/go.mod h1:q8bcK0KcYlCgd9e7WYLm9LpyS+YeLd8JVDW6WezmKEw=
 github.com/gobwas/ws v1.0.2/go.mod h1:szmBTxLgaFppYjEmNtny/v3w89xOydFnnZMcgRRu/EM=
@@ -195,8 +195,8 @@ github.com/mattn/go-runewidth v0.0.9/go.mod h1:H031xJmbD/WCDINGzjvQ9THkh0rPKHF+m
 github.com/mattn/goveralls v0.0.2/go.mod h1:8d1ZMHsd7fW6IRPKQh46F2WRpyib5/X4FOpevwGNQEw=
 github.com/mediocregopher/radix/v3 v3.4.2/go.mod h1:8FL3F6UQRXHXIBSPUs5h0RybMF8i4n7wVopoX3x7Bv8=
 github.com/microcosm-cc/bluemonday v1.0.2/go.mod h1:iVP4YcDBq+n/5fb23BhYFvIMq/leAFZyRl6bYmGDlGc=
-github.com/miekg/dns v1.1.30 h1:Qww6FseFn8PRfw07jueqIXqodm0JKiiKuK0DeXSqfyo=
+github.com/miekg/dns v1.1.41 h1:WMszZWJG0XmzbK9FEmzH2TVcqYzFesusSIB41b8KHxY=
-github.com/miekg/dns v1.1.30/go.mod h1:KNUDUusw/aVsxyTYZM1oqvCicbwhgbNgztCETuNZ7xM=
+github.com/miekg/dns v1.1.41/go.mod h1:p6aan82bvRIyn+zDIv9xYNUpwa73JcSh9BKwknJysuI=
 github.com/mitchellh/go-homedir v1.1.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
 github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=
 github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
@@ -223,8 +223,6 @@ github.com/pingcap/errors v0.11.4/go.mod h1:Oi8TUi2kEtXXLMJk9l1cGmz20kV3TaQ0usTw
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
-github.com/pkg/math v0.0.0-20141027224758-f2ed9e40e245 h1:gk/AF9SGRj+RafNCoDcS3RRscb8S4BVbvqODOgWA7/8=
-github.com/pkg/math v0.0.0-20141027224758-f2ed9e40e245/go.mod h1:2dhPPj2Li3DXrSY2U2ADdZy2B7sjQsT57lqENx1+FSE=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/russross/blackfriday v1.5.2 h1:HyvC0ARfnZBqnXwABFeSZHpKvJHJJfPz81GNueLj0oo=
@@ -264,6 +262,11 @@ github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/therecipe/qt v0.0.0-20200701200531-7f61353ee73e h1:G0DQ/TRQyrEZjtLlLwevFjaRiG8eeCMlq9WXQ2OO2bk=
 github.com/therecipe/qt v0.0.0-20200701200531-7f61353ee73e/go.mod h1:SUUR2j3aE1z6/g76SdD6NwACEpvCxb3fvG82eKbD6us=
+github.com/therecipe/qt v0.0.0-20200904063919-c0c124a5770d h1:T+d8FnaLSvM/1BdlDXhW4d5dr2F07bAbB+LpgzMxx+o=
+github.com/therecipe/qt/internal/binding/files/docs/5.12.0 v0.0.0-20200904063919-c0c124a5770d h1:hAZyEG2swPRWjF0kqqdGERXUazYnRJdAk4a58f14z7Y=
+github.com/therecipe/qt/internal/binding/files/docs/5.12.0 v0.0.0-20200904063919-c0c124a5770d/go.mod h1:7m8PDYDEtEVqfjoUQc2UrFqhG0CDmoVJjRlQxexndFc=
+github.com/therecipe/qt/internal/binding/files/docs/5.13.0 v0.0.0-20200904063919-c0c124a5770d h1:AJRoBel/g9cDS+yE8BcN3E+TDD/xNAguG21aoR8DAIE=
+github.com/therecipe/qt/internal/binding/files/docs/5.13.0 v0.0.0-20200904063919-c0c124a5770d/go.mod h1:mH55Ek7AZcdns5KPp99O0bg+78el64YCYWHiQKrOdt4=
 github.com/ugorji/go v1.1.4/go.mod h1:uQMGLiO92mf5W77hV/PUCpI3pbzQx3CRekS0kk+RGrc=
 github.com/ugorji/go v1.1.7/go.mod h1:kZn38zHttfInRq0xu/PH0az30d+z6vm202qpg1oXVMw=
 github.com/ugorji/go/codec v0.0.0-20181204163529-d75b2dcb6bc8/go.mod h1:VFNgLljTbGfSG7qAOspJ7OScBnGdDN/yBr0sguwnwf0=
@@ -307,16 +310,18 @@ golang.org/x/net v0.0.0-20190420063019-afa5a82059c6/go.mod h1:t9HGtf8HONx5eT2rtn
 golang.org/x/net v0.0.0-20190503192946-f4e77d36d62c/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20190827160401-ba9fcec4b297/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
-golang.org/x/net v0.0.0-20190923162816-aa69164e4478/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20191209160850-c0dbc17a3553/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20200202094626-16171245cfb2/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
-golang.org/x/net v0.0.0-20200513185701-a91f0712d120/go.mod h1:qpuaurCH72eLCgpAm/N6yyVIVM9cpaDIP3A8BGJEC5A=
+golang.org/x/net v0.0.0-20210226172049-e18ecbb05110 h1:qWPm9rbaAMKs8Bq/9LRpbMqxWRVUAQwMI9fVrssnTfw=
-golang.org/x/net v0.0.0-20200707034311-ab3426394381 h1:VXak5I6aEWmAXeQjA+QSZzlgNrpq9mjcfDemuexIKsU=
+golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
-golang.org/x/net v0.0.0-20200707034311-ab3426394381/go.mod h1:/O7V0waA8r7cgGh81Ro3o1hOxt32SMVPicZroKQ2sZA=
+golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4 h1:4nGaVu0QrbjT/AK2PRLuQfQuh6DJve+pELhqTdAj3x0=
+golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4/go.mod h1:p54w0d4576C0XHj96bSt6lcn1PtDYWL6XObtHCRCNQM=
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20190911185100-cd5d95a43a6e h1:vcxGaoTs7kV8m5Np9uUNQin4BrLOthgV7252N8V+FwY=
 golang.org/x/sync v0.0.0-20190911185100-cd5d95a43a6e/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20210220032951-036812b2e83c h1:5KslGYwFpkhGh+Q16bwMP3cOontH8FOep7tGV86Y7SQ=
+golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20180905080454-ebe1bf3edb33/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20180909124046-d0be0721c37e/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20181205085412-a5c9d58dba9a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
@@ -327,14 +332,19 @@ golang.org/x/sys v0.0.0-20190419153524-e8e3143a4f4a/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20190422165155-953cdadca894/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190626221950-04f50cda93cb/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190813064441-fde4db37ae7a/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20190924154521-2837fb4f24fe/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20191026070338-33540a1f6037/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200202164722-d101bd2416d5/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd h1:xhmwyvizuTgC2qz7ZlMluP20uW+C3Rm0FD/WLDX8884=
+golang.org/x/sys v0.0.0-20201119102817-f84b799fce68 h1:nxC68pudNYkKU6jWhgrqdreuFiOQWj1Fs7T3VrH4Pjw=
-golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210303074136-134d130e1a04 h1:cEhElsAv9LUt9ZUUocxzWe05oFLVd+AA2nstydTeI8g=
+golang.org/x/sys v0.0.0-20210303074136-134d130e1a04/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210330210617-4fbd30eecc44 h1:Bli41pIlzTzf3KEY06n+xnzK/BESIg2ze4Pgfh/aI8c=
+golang.org/x/sys v0.0.0-20210330210617-4fbd30eecc44/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/term v0.0.0-20201117132131-f5c789dd3221/go.mod h1:Nr5EML6q2oocZ2LXRh80K7BxOlk5/8JxuGnuhpl+muw=
+golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
+golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.5-0.20201125200606-c27b9fd57aec h1:A1qYjneJuzBZZ2gIB8rd6zrfq6l7SoEMJ8EsSilNK/U=
 golang.org/x/text v0.3.5-0.20201125200606-c27b9fd57aec/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
@@ -345,7 +355,6 @@ golang.org/x/tools v0.0.0-20190328211700-ab21143f2384/go.mod h1:LCzVGOaR6xXOjkQ3
 golang.org/x/tools v0.0.0-20190420181800-aa740d480789/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs=
 golang.org/x/tools v0.0.0-20190425150028-36563e24a262/go.mod h1:RgjU9mgBXZiqYHBnxXauZ1Gv1EHHAz9KjViQ78xBX0Q=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
-golang.org/x/tools v0.0.0-20191216052735-49a3e744a425/go.mod h1:TB2adYChydJhpapKDTa4BR/hXlZSLoq2Wpct/0txZ28=
 golang.org/x/tools v0.0.0-20200117012304-6edc0a871e69 h1:yBHHx+XZqXJBm6Exke3N7V9gnlsyXxoCPEb1yVenjfk=
 golang.org/x/tools v0.0.0-20200117012304-6edc0a871e69/go.mod h1:TB2adYChydJhpapKDTa4BR/hXlZSLoq2Wpct/0txZ28=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

internal/app/base/base.go

@@ -23,7 +23,7 @@
 //  - persistent settings
 //  - event listener
 //  - credentials store
-//  - pmapi ClientManager
+//  - pmapi Manager
 // In addition, the base initialises logging and reacts to command line arguments
 // which control the log verbosity and enable cpu/memory profiling.
 package base
@@ -69,7 +69,7 @@ const (
 	flagMemProfileShort = "m"
 	flagLogLevel        = "log-level"
 	flagLogLevelShort   = "l"
-	// FlagCLI indicate to start with command line interface
+	// FlagCLI indicate to start with command line interface.
 	FlagCLI      = "cli"
 	flagCLIShort = "c"
 	flagRestart  = "restart"
@@ -85,7 +85,7 @@ type Base struct {
 	Cache          *cache.Cache
 	Listener       listener.Listener
 	Creds          *credentials.Store
-	CM             *pmapi.ClientManager
+	CM             pmapi.Manager
 	CookieJar      *cookies.Jar
 	UserAgent      *useragent.UserAgent
 	Updater        *updater.Updater
@@ -181,13 +181,23 @@ func New( // nolint[funlen]
 		kc = keychain.NewMissingKeychain()
 	}
 
+	cfg := pmapi.NewConfig(configName, constants.Version)
+	cfg.GetUserAgent = userAgent.String
+	cfg.UpgradeApplicationHandler = func() { listener.Emit(events.UpgradeApplicationEvent, "") }
+	cfg.TLSIssueHandler = func() { listener.Emit(events.TLSCertIssue, "") }
+
+	cm := pmapi.New(cfg)
+
+	cm.AddConnectionObserver(pmapi.NewConnectionObserver(
+		func() { listener.Emit(events.InternetOffEvent, "") },
+		func() { listener.Emit(events.InternetOnEvent, "") },
+	))
+
 	jar, err := cookies.NewCookieJar(settingsObj)
 	if err != nil {
 		return nil, err
 	}
 
-	cm := pmapi.NewClientManager(getAPIConfig(configName, listener), userAgent)
-	cm.SetRoundTripper(pmapi.GetRoundTripper(cm, listener))
 	cm.SetCookieJar(jar)
 
 	key, err := crypto.NewKeyFromArmored(updater.DefaultPublicKey)
@@ -328,6 +338,7 @@ func (b *Base) run(appMainLoop func(*Base, *cli.Context) error) cli.ActionFunc {
 		}
 
 		logging.SetLevel(c.String(flagLogLevel))
+		b.CM.SetLogging(logrus.WithField("pkg", "pmapi"), logrus.GetLevel() == logrus.TraceLevel)
 
 		logrus.
 			WithField("appName", b.Name).
@@ -375,13 +386,3 @@ func (b *Base) doTeardown() error {
 
 	return nil
 }
-
-func getAPIConfig(configName string, listener listener.Listener) *pmapi.ClientConfig {
-	apiConfig := pmapi.GetAPIConfig(configName, constants.Version)
-
-	apiConfig.ConnectionOffHandler = func() { listener.Emit(events.InternetOffEvent, "") }
-	apiConfig.ConnectionOnHandler = func() { listener.Emit(events.InternetOnEvent, "") }
-	apiConfig.UpgradeApplicationHandler = func() { listener.Emit(events.UpgradeApplicationEvent, "") }
-
-	return apiConfig
-}

internal/app/base/migration.go

@@ -29,10 +29,12 @@ import (
 // migrateFiles migrates files from their old (pre-refactor) locations to their new locations.
 // We can remove this eventually.
 //
-// | entity |               old location                |            new location                |
+// | entity    |               old location                |            new location                |
-// |--------|-------------------------------------------|----------------------------------------|
+// |-----------|-------------------------------------------|----------------------------------------|
-// | prefs  | ~/.cache/protonmail/<app>/c11/prefs.json  | ~/.config/protonmail/<app>/prefs.json  |
+// | prefs     | ~/.cache/protonmail/<app>/c11/prefs.json  | ~/.config/protonmail/<app>/prefs.json  |
-// | c11    | ~/.cache/protonmail/<app>/c11             | ~/.cache/protonmail/<app>/cache/c11    |
+// | c11 1.5.x | ~/.cache/protonmail/<app>/c11             | ~/.cache/protonmail/<app>/cache/c11    |
+// | c11 1.6.x | ~/.cache/protonmail/<app>/cache/c11       | ~/.config/protonmail/<app>/cache/c11   |
+// | updates   | ~/.cache/protonmail/<app>/updates         | ~/.config/protonmail/<app>/updates     |.
 func migrateFiles(configName string) error {
 	locationsProvider, err := locations.NewDefaultProvider(filepath.Join(constants.VendorName, configName))
 	if err != nil {
@@ -41,43 +43,89 @@ func migrateFiles(configName string) error {
 
 	locations := locations.New(locationsProvider, configName)
 	userCacheDir := locationsProvider.UserCache()
+
+	if err := migratePrefsFrom15x(locations, userCacheDir); err != nil {
+		return err
+	}
+	if err := migrateCacheFromBoth15xAnd16x(locations, userCacheDir); err != nil {
+		return err
+	}
+	if err := migrateUpdatesFrom16x(configName, locations); err != nil { //nolint[revive] It is more clear to structure this way
+		return err
+	}
+	return nil
+}
+
+func migratePrefsFrom15x(locations *locations.Locations, userCacheDir string) error {
 	newSettingsDir, err := locations.ProvideSettingsPath()
 	if err != nil {
 		return err
 	}
 
-	if err := moveIfExists(
+	return moveIfExists(
 		filepath.Join(userCacheDir, "c11", "prefs.json"),
 		filepath.Join(newSettingsDir, "prefs.json"),
-	); err != nil {
+	)
-		return err
+}
-	}
 
-	newCacheDir, err := locations.ProvideCachePath()
+func migrateCacheFromBoth15xAnd16x(locations *locations.Locations, userCacheDir string) error {
+	olderCacheDir := userCacheDir
+	newerCacheDir := locations.GetOldCachePath()
+	latestCacheDir, err := locations.ProvideCachePath()
 	if err != nil {
 		return err
 	}
 
+	// Migration for versions before 1.6.x.
 	if err := moveIfExists(
-		filepath.Join(userCacheDir, "c11"),
+		filepath.Join(olderCacheDir, "c11"),
-		filepath.Join(newCacheDir, "c11"),
+		filepath.Join(latestCacheDir, "c11"),
 	); err != nil {
 		return err
 	}
 
-	return nil
+	// Migration for versions 1.6.x.
+	return moveIfExists(
+		filepath.Join(newerCacheDir, "c11"),
+		filepath.Join(latestCacheDir, "c11"),
+	)
+}
+
+func migrateUpdatesFrom16x(configName string, locations *locations.Locations) error {
+	// In order to properly update Bridge 1.6.X and higher we need to
+	// change the launcher first. Since this is not part of automatic
+	// updates the migration must wait until manual update. Until that
+	// we need to keep old path.
+	if configName == "bridge" {
+		return nil
+	}
+
+	oldUpdatesPath := locations.GetOldUpdatesPath()
+	// Do not use ProvideUpdatesPath, that creates dir right away.
+	newUpdatesPath := locations.GetUpdatesPath()
+
+	return moveIfExists(oldUpdatesPath, newUpdatesPath)
 }
 
 func moveIfExists(source, destination string) error {
+	l := logrus.WithField("source", source).WithField("destination", destination)
+
 	if _, err := os.Stat(source); os.IsNotExist(err) {
-		logrus.WithField("source", source).WithField("destination", destination).Debug("No need to migrate file")
+		l.Info("No need to migrate file, source doesn't exist")
 		return nil
 	}
 
 	if _, err := os.Stat(destination); !os.IsNotExist(err) {
-		logrus.WithField("source", source).WithField("destination", destination).Debug("No need to migrate file")
+		// Once migrated, files should not stay in source anymore. Therefore
+		// if some files are still in source location but target already exist,
+		// it's suspicious. Could happen by installing new version, then the
+		// old one because of some reason, and then the new one again.
+		// Good to see as warning because it could be a reason why Bridge is
+		// behaving weirdly, like wrong configuration, or db re-sync and so on.
+		l.Warn("No need to migrate file, target already exists")
 		return nil
 	}
 
+	l.Info("Migrating files")
 	return os.Rename(source, destination)
 }

internal/app/bridge/bridge.go

@@ -95,6 +95,7 @@ func run(b *base.Base, c *cli.Context) error { // nolint[funlen]
 		smtpPort := b.Settings.GetInt(settings.SMTPPortKey)
 		useSSL := b.Settings.GetBool(settings.SMTPSSLKey)
 		smtp.NewSMTPServer(
+			b.CrashHandler,
 			c.Bool(flagLogSMTP),
 			smtpPort, useSSL, tlsConfig, smtpBackend, b.Listener).ListenAndServe()
 	}()
@@ -189,9 +190,10 @@ func generateTLSCerts(b *base.Base) error {
 }
 
 func checkAndHandleUpdate(u types.Updater, f frontend.Frontend, autoUpdate bool) {
+	log := logrus.WithField("pkg", "app/bridge")
 	version, err := u.Check()
 	if err != nil {
-		logrus.WithError(err).Error("An error occurred while checking for updates")
+		log.WithError(err).Error("An error occurred while checking for updates")
 		return
 	}
 
@@ -201,11 +203,11 @@ func checkAndHandleUpdate(u types.Updater, f frontend.Frontend, autoUpdate bool)
 	f.SetVersion(version)
 
 	if !u.IsUpdateApplicable(version) {
-		logrus.Debug("No need to update")
+		log.Info("No need to update")
 		return
 	}
 
-	logrus.WithField("version", version.Version).Info("An update is available")
+	log.WithField("version", version.Version).Info("An update is available")
 
 	if !autoUpdate {
 		f.NotifyManualUpdate(version, u.CanInstall(version))
@@ -213,16 +215,16 @@ func checkAndHandleUpdate(u types.Updater, f frontend.Frontend, autoUpdate bool)
 	}
 
 	if !u.CanInstall(version) {
-		logrus.Info("A manual update is required")
+		log.Info("A manual update is required")
 		f.NotifySilentUpdateError(updater.ErrManualUpdateRequired)
 		return
 	}
 
 	if err := u.InstallUpdate(version); err != nil {
 		if errors.Cause(err) == updater.ErrDownloadVerify {
-			logrus.WithError(err).Warning("Skipping update installation due to temporary error")
+			log.WithError(err).Warning("Skipping update installation due to temporary error")
 		} else {
-			logrus.WithError(err).Error("The update couldn't be installed")
+			log.WithError(err).Error("The update couldn't be installed")
 			f.NotifySilentUpdateError(err)
 		}
 

internal/app/ie/ie.go

@@ -28,8 +28,6 @@ import (
 	"github.com/ProtonMail/proton-bridge/internal/frontend"
 	"github.com/ProtonMail/proton-bridge/internal/frontend/types"
 	"github.com/ProtonMail/proton-bridge/internal/importexport"
-	"github.com/ProtonMail/proton-bridge/internal/updater"
-	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 	"github.com/urfave/cli/v2"
 )
@@ -88,10 +86,11 @@ func run(b *base.Base, c *cli.Context) error {
 	return f.Loop()
 }
 
-func checkAndHandleUpdate(u types.Updater, f frontend.Frontend, autoUpdate bool) {
+func checkAndHandleUpdate(u types.Updater, f frontend.Frontend, autoUpdate bool) { //nolint[unparam]
+	log := logrus.WithField("pkg", "app/ie")
 	version, err := u.Check()
 	if err != nil {
-		logrus.WithError(err).Error("An error occurred while checking for updates")
+		log.WithError(err).Error("An error occurred while checking for updates")
 		return
 	}
 
@@ -101,33 +100,11 @@ func checkAndHandleUpdate(u types.Updater, f frontend.Frontend, autoUpdate bool)
 	f.SetVersion(version)
 
 	if !u.IsUpdateApplicable(version) {
-		logrus.Debug("No need to update")
+		log.Info("No need to update")
 		return
 	}
 
-	logrus.WithField("version", version.Version).Info("An update is available")
+	log.WithField("version", version.Version).Info("An update is available")
 
-	if !autoUpdate {
+	f.NotifyManualUpdate(version, u.CanInstall(version))
-		f.NotifyManualUpdate(version, u.CanInstall(version))
-		return
-	}
-
-	if !u.CanInstall(version) {
-		logrus.Info("A manual update is required")
-		f.NotifySilentUpdateError(updater.ErrManualUpdateRequired)
-		return
-	}
-
-	if err := u.InstallUpdate(version); err != nil {
-		if errors.Cause(err) == updater.ErrDownloadVerify {
-			logrus.WithError(err).Warning("Skipping update installation due to temporary error")
-		} else {
-			logrus.WithError(err).Error("The update couldn't be installed")
-			f.NotifySilentUpdateError(err)
-		}
-
-		return
-	}
-
-	f.NotifySilentUpdateInstalled()
 }

internal/bridge/bridge.go

@@ -19,6 +19,7 @@
 package bridge
 
 import (
+	"context"
 	"fmt"
 	"strconv"
 	"time"
@@ -44,7 +45,7 @@ type Bridge struct {
 
 	locations     Locator
 	settings      SettingsProvider
-	clientManager users.ClientManager
+	clientManager pmapi.Manager
 	updater       Updater
 	versioner     Versioner
 }
@@ -56,7 +57,7 @@ func New(
 	sentryReporter *sentry.Reporter,
 	panicHandler users.PanicHandler,
 	eventListener listener.Listener,
-	clientManager users.ClientManager,
+	clientManager pmapi.Manager,
 	credStorer users.CredentialsStorer,
 	updater Updater,
 	versioner Versioner,
@@ -67,7 +68,7 @@ func New(
 		clientManager.AllowProxy()
 	}
 
-	storeFactory := newStoreFactory(cache, sentryReporter, panicHandler, clientManager, eventListener)
+	storeFactory := newStoreFactory(cache, sentryReporter, panicHandler, eventListener)
 	u := users.New(locations, panicHandler, eventListener, clientManager, credStorer, storeFactory, true)
 	b := &Bridge{
 		Users: u,
@@ -118,28 +119,15 @@ func (b *Bridge) heartbeat() {
 
 // ReportBug reports a new bug from the user.
 func (b *Bridge) ReportBug(osType, osVersion, description, accountName, address, emailClient string) error {
-	c := b.clientManager.GetAnonymousClient()
+	return b.clientManager.ReportBug(context.Background(), pmapi.ReportBugReq{
-	defer c.Logout()
-
-	title := "[Bridge] Bug"
-	report := pmapi.ReportReq{
 		OS:          osType,
 		OSVersion:   osVersion,
 		Browser:     emailClient,
-		Title:       title,
+		Title:       "[Bridge] Bug",
 		Description: description,
 		Username:    accountName,
 		Email:       address,
-	}
+	})
-
-	if err := c.Report(report); err != nil {
-		log.Error("Reporting bug failed: ", err)
-		return err
-	}
-
-	log.Info("Bug successfully reported")
-
-	return nil
 }
 
 // GetUpdateChannel returns currently set update channel.

internal/bridge/store_factory.go

@@ -31,7 +31,6 @@ type storeFactory struct {
 	cache          Cacher
 	sentryReporter *sentry.Reporter
 	panicHandler   users.PanicHandler
-	clientManager  users.ClientManager
 	eventListener  listener.Listener
 	storeCache     *store.Cache
 }
@@ -40,14 +39,12 @@ func newStoreFactory(
 	cache Cacher,
 	sentryReporter *sentry.Reporter,
 	panicHandler users.PanicHandler,
-	clientManager users.ClientManager,
 	eventListener listener.Listener,
 ) *storeFactory {
 	return &storeFactory{
 		cache:          cache,
 		sentryReporter: sentryReporter,
 		panicHandler:   panicHandler,
-		clientManager:  clientManager,
 		eventListener:  eventListener,
 		storeCache:     store.NewCache(cache.GetIMAPCachePath()),
 	}
@@ -56,7 +53,7 @@ func newStoreFactory(
 // New creates new store for given user.
 func (f *storeFactory) New(user store.BridgeUser) (*store.Store, error) {
 	storePath := getUserStorePath(f.cache.GetDBDir(), user.ID())
-	return store.New(f.sentryReporter, f.panicHandler, user, f.clientManager, f.eventListener, storePath, f.storeCache)
+	return store.New(f.sentryReporter, f.panicHandler, user, f.eventListener, storePath, f.storeCache)
 }
 
 // Remove removes all store files for given user.

internal/config/settings/settings.go

@@ -78,7 +78,7 @@ func (s *Settings) setDefaultValues() {
 	s.setDefault(ReportOutgoingNoEncKey, "false")
 	s.setDefault(LastVersionKey, "")
 	s.setDefault(UpdateChannelKey, "")
-	s.setDefault(RolloutKey, fmt.Sprintf("%v", rand.Float64()))
+	s.setDefault(RolloutKey, fmt.Sprintf("%v", rand.Float64())) //nolint[gosec] G404 It is OK to use weak random number generator here
 	s.setDefault(PreferredKeychainKey, "")
 
 	s.setDefault(APIPortKey, DefaultAPIPort)

internal/config/tls/tls.go

@@ -122,11 +122,7 @@ func (t *TLS) GenerateCerts(template *x509.Certificate) error {
 	}
 	defer keyOut.Close() // nolint[errcheck]
 
-	if err := pem.Encode(keyOut, &pem.Block{Type: "RSA PRIVATE KEY", Bytes: x509.MarshalPKCS1PrivateKey(priv)}); err != nil {
+	return pem.Encode(keyOut, &pem.Block{Type: "RSA PRIVATE KEY", Bytes: x509.MarshalPKCS1PrivateKey(priv)})
-		return err
-	}
-
-	return nil
 }
 
 // GetConfig tries to load TLS config or generate new one which is then returned.
@@ -148,6 +144,7 @@ func (t *TLS) GetConfig() (*tls.Config, error) {
 	caCertPool := x509.NewCertPool()
 	caCertPool.AddCert(c.Leaf)
 
+	// nolint[gosec]: We need to support older TLS versions for AppleMail and Outlook.
 	return &tls.Config{
 		Certificates: []tls.Certificate{c},
 		ServerName:   "127.0.0.1",

internal/config/useragent/platform.go

@@ -25,8 +25,20 @@ import (
 	"github.com/Masterminds/semver/v3"
 )
 
-// IsCatalinaOrNewer checks whether host is MacOS Catalina 10.15.x or higher.
+// IsCatalinaOrNewer checks whether the host is MacOS Catalina 10.15.x or higher.
 func IsCatalinaOrNewer() bool {
+	return isThisDarwinNewerOrEqual(getMinCatalina())
+}
+
+// IsBigSurOrNewer checks whether the host is MacOS BigSur 10.16.x or higher.
+func IsBigSurOrNewer() bool {
+	return isThisDarwinNewerOrEqual(getMinBigSur())
+}
+
+func getMinCatalina() *semver.Version { return semver.MustParse("10.15.0") }
+func getMinBigSur() *semver.Version   { return semver.MustParse("10.16.0") }
+
+func isThisDarwinNewerOrEqual(minVersion *semver.Version) bool {
 	if runtime.GOOS != "darwin" {
 		return false
 	}
@@ -36,16 +48,14 @@ func IsCatalinaOrNewer() bool {
 		return false
 	}
 
-	return isVersionCatalinaOrNewer(strings.TrimSpace(string(rawVersion)))
+	return isVersionEqualOrNewer(minVersion, strings.TrimSpace(string(rawVersion)))
 }
 
-func isVersionCatalinaOrNewer(rawVersion string) bool {
+// isVersionEqualOrNewer is separated to be able to run test on other than darwin.
+func isVersionEqualOrNewer(minVersion *semver.Version, rawVersion string) bool {
 	semVersion, err := semver.NewVersion(rawVersion)
 	if err != nil {
 		return false
 	}
-
-	minVersion := semver.MustParse("10.15.0")
-
 	return semVersion.GreaterThan(minVersion) || semVersion.Equal(minVersion)
 }

internal/config/useragent/platform_test.go

@@ -38,7 +38,27 @@ func TestIsVersionCatalinaOrNewer(t *testing.T) {
 	}
 
 	for args, exp := range testData {
-		got := isVersionCatalinaOrNewer(args.version)
+		got := isVersionEqualOrNewer(getMinCatalina(), args.version)
+		assert.Equal(t, exp, got, "version %v", args.version)
+	}
+}
+
+func TestIsVersionBigSurOrNewer(t *testing.T) {
+	testData := map[struct{ version string }]bool{
+		{""}:         false,
+		{"9.0.0"}:    false,
+		{"9.15.0"}:   false,
+		{"10.13.0"}:  false,
+		{"10.14.0"}:  false,
+		{"10.14.99"}: false,
+		{"10.15.0"}:  false,
+		{"10.16.0"}:  true,
+		{"11.0.0"}:   true,
+		{"11.1"}:     true,
+	}
+
+	for args, exp := range testData {
+		got := isVersionEqualOrNewer(getMinBigSur(), args.version)
 		assert.Equal(t, exp, got, "version %v", args.version)
 	}
 }

internal/frontend/autoconfig/applemail.go

@@ -29,10 +29,15 @@ import (
 	"time"
 
 	"github.com/ProtonMail/proton-bridge/internal/bridge"
+	"github.com/ProtonMail/proton-bridge/internal/config/useragent"
 	"github.com/ProtonMail/proton-bridge/internal/frontend/types"
 	"github.com/ProtonMail/proton-bridge/pkg/mobileconfig"
 )
 
+const (
+	bigSurPreferncesPane = "/System/Library/PreferencePanes/Profiles.prefPane"
+)
+
 func init() { //nolint[gochecknoinit]
 	available = append(available, &appleMail{})
 }
@@ -43,7 +48,22 @@ func (c *appleMail) Name() string {
 	return "Apple Mail"
 }
 
-func (c *appleMail) Configure(imapPort, smtpPort int, imapSSL, smtpSSL bool, user types.User, addressIndex int) error { //nolint[funlen]
+func (c *appleMail) Configure(imapPort, smtpPort int, imapSSL, smtpSSL bool, user types.User, addressIndex int) error {
+	mc := prepareMobileConfig(imapPort, smtpPort, imapSSL, smtpSSL, user, addressIndex)
+
+	confPath, err := saveConfigTemporarily(mc)
+	if err != nil {
+		return err
+	}
+
+	if useragent.IsBigSurOrNewer() {
+		return exec.Command("open", bigSurPreferncesPane, confPath).Run() //nolint[gosec] G204: open command is safe, mobileconfig is generated by us
+	}
+
+	return exec.Command("open", confPath).Run() //nolint[gosec] G204: open command is safe, mobileconfig is generated by us
+}
+
+func prepareMobileConfig(imapPort, smtpPort int, imapSSL, smtpSSL bool, user types.User, addressIndex int) *mobileconfig.Config {
 	var addresses string
 	var displayName string
 
@@ -62,7 +82,7 @@ func (c *appleMail) Configure(imapPort, smtpPort int, imapSSL, smtpSSL bool, use
 
 	timestamp := strconv.FormatInt(time.Now().Unix(), 10)
 
-	mc := &mobileconfig.Config{
+	return &mobileconfig.Config{
 		EmailAddress: addresses,
 		DisplayName:  displayName,
 		Identifier:   "protonmail " + displayName + timestamp,
@@ -80,10 +100,12 @@ func (c *appleMail) Configure(imapPort, smtpPort int, imapSSL, smtpSSL bool, use
 			Username: displayName,
 		},
 	}
+}
 
+func saveConfigTemporarily(mc *mobileconfig.Config) (fname string, err error) {
 	dir, err := ioutil.TempDir("", "protonmail-autoconfig")
 	if err != nil {
-		return err
+		return
 	}
 
 	// Make sure the temporary file is deleted.
@@ -93,16 +115,17 @@ func (c *appleMail) Configure(imapPort, smtpPort int, imapSSL, smtpSSL bool, use
 	})()
 
 	// Make sure the file is only readable for the current user.
-	f, err := os.OpenFile(filepath.Join(dir, "protonmail.mobileconfig"), os.O_RDWR|os.O_CREATE, 0600)
+	fname = filepath.Clean(filepath.Join(dir, "protonmail.mobileconfig"))
+	f, err := os.OpenFile(fname, os.O_RDWR|os.O_CREATE, 0600)
 	if err != nil {
-		return err
+		return
 	}
 
-	if err := mc.WriteOut(f); err != nil {
+	if err = mc.WriteOut(f); err != nil {
 		_ = f.Close()
-		return err
+		return
 	}
 	_ = f.Close()
 
-	return exec.Command("open", f.Name()).Run() // nolint[gosec]
+	return
 }

internal/frontend/cli-ie/accounts.go

@@ -18,6 +18,7 @@
 package cliie
 
 import (
+	"context"
 	"strings"
 
 	"github.com/abiosoft/ishell"
@@ -25,7 +26,7 @@ import (
 
 func (f *frontendCLI) listAccounts(c *ishell.Context) {
 	spacing := "%-2d: %-20s (%-15s, %-15s)\n"
-	f.Printf(bold(strings.Replace(spacing, "d", "s", -1)), "#", "account", "status", "address mode")
+	f.Printf(bold(strings.ReplaceAll(spacing, "d", "s")), "#", "account", "status", "address mode")
 	for idx, user := range f.ie.GetUsers() {
 		connected := "disconnected"
 		if user.IsConnected() {
@@ -79,7 +80,7 @@ func (f *frontendCLI) loginAccount(c *ishell.Context) { // nolint[funlen]
 			return
 		}
 
-		err = client.Auth2FA(twoFactor, auth)
+		err = client.Auth2FA(context.Background(), twoFactor)
 		if err != nil {
 			f.processAPIError(err)
 			return

internal/frontend/cli-ie/frontend.go

@@ -84,11 +84,6 @@ func New( //nolint[funlen]
 		Aliases: []string{"u", "version", "v"},
 		Func:    fe.checkUpdates,
 	})
-	checkCmd.AddCmd(&ishell.Cmd{Name: "internet",
-		Help:    "check internet connection. (aliases: i, conn, connection)",
-		Aliases: []string{"i", "con", "connection"},
-		Func:    fe.checkInternetConnection,
-	})
 	fe.AddCmd(checkCmd)
 
 	// Print info commands.
@@ -177,13 +172,13 @@ func New( //nolint[funlen]
 }
 
 func (f *frontendCLI) watchEvents() {
-	errorCh := f.getEventChannel(events.ErrorEvent)
+	errorCh := f.eventListener.ProvideChannel(events.ErrorEvent)
-	credentialsErrorCh := f.getEventChannel(events.CredentialsErrorEvent)
+	credentialsErrorCh := f.eventListener.ProvideChannel(events.CredentialsErrorEvent)
-	internetOffCh := f.getEventChannel(events.InternetOffEvent)
+	internetOffCh := f.eventListener.ProvideChannel(events.InternetOffEvent)
-	internetOnCh := f.getEventChannel(events.InternetOnEvent)
+	internetOnCh := f.eventListener.ProvideChannel(events.InternetOnEvent)
-	addressChangedLogoutCh := f.getEventChannel(events.AddressChangedLogoutEvent)
+	addressChangedLogoutCh := f.eventListener.ProvideChannel(events.AddressChangedLogoutEvent)
-	logoutCh := f.getEventChannel(events.LogoutEvent)
+	logoutCh := f.eventListener.ProvideChannel(events.LogoutEvent)
-	certIssue := f.getEventChannel(events.TLSCertIssue)
+	certIssue := f.eventListener.ProvideChannel(events.TLSCertIssue)
 	for {
 		select {
 		case errorDetails := <-errorCh:
@@ -208,13 +203,6 @@ func (f *frontendCLI) watchEvents() {
 	}
 }
 
-func (f *frontendCLI) getEventChannel(event string) <-chan string {
-	ch := make(chan string)
-	f.eventListener.Add(event, ch)
-	f.eventListener.RetryEmit(event)
-	return ch
-}
-
 // Loop starts the frontend loop with an interactive shell.
 func (f *frontendCLI) Loop() error {
 	f.Print(`

internal/frontend/cli-ie/importexport.go

@@ -38,7 +38,7 @@ func (f *frontendCLI) importLocalMessages(c *ishell.Context) {
 		return
 	}
 
-	t, err := f.ie.GetLocalImporter(user.GetPrimaryAddress(), path)
+	t, err := f.ie.GetLocalImporter(user.Username(), user.GetPrimaryAddress(), path)
 	f.transfer(t, err, false, true)
 }
 
@@ -68,7 +68,7 @@ func (f *frontendCLI) importRemoteMessages(c *ishell.Context) {
 		return
 	}
 
-	t, err := f.ie.GetRemoteImporter(user.GetPrimaryAddress(), username, password, host, port)
+	t, err := f.ie.GetRemoteImporter(user.Username(), user.GetPrimaryAddress(), username, password, host, port)
 	f.transfer(t, err, false, true)
 }
 
@@ -81,7 +81,7 @@ func (f *frontendCLI) exportMessagesToEML(c *ishell.Context) {
 		return
 	}
 
-	t, err := f.ie.GetEMLExporter(user.GetPrimaryAddress(), path)
+	t, err := f.ie.GetEMLExporter(user.Username(), user.GetPrimaryAddress(), path)
 	f.transfer(t, err, true, false)
 }
 
@@ -94,7 +94,7 @@ func (f *frontendCLI) exportMessagesToMBOX(c *ishell.Context) {
 		return
 	}
 
-	t, err := f.ie.GetMBOXExporter(user.GetPrimaryAddress(), path)
+	t, err := f.ie.GetMBOXExporter(user.Username(), user.GetPrimaryAddress(), path)
 	f.transfer(t, err, true, false)
 }
 

internal/frontend/cli-ie/system.go

@@ -29,14 +29,6 @@ func (f *frontendCLI) restart(c *ishell.Context) {
 	}
 }
 
-func (f *frontendCLI) checkInternetConnection(c *ishell.Context) {
-	if f.ie.CheckConnection() == nil {
-		f.Println("Internet connection is available.")
-	} else {
-		f.Println("Can not contact the server, please check your internet connection.")
-	}
-}
-
 func (f *frontendCLI) printLogDir(c *ishell.Context) {
 	if path, err := f.locations.ProvideLogsPath(); err != nil {
 		f.Println("Failed to determine location of log files")

internal/frontend/cli-ie/utils.go

@@ -20,7 +20,7 @@ package cliie
 import (
 	"strings"
 
-	pmapi "github.com/ProtonMail/proton-bridge/pkg/pmapi"
+	"github.com/ProtonMail/proton-bridge/pkg/pmapi"
 	"github.com/fatih/color"
 )
 
@@ -71,7 +71,7 @@ func (f *frontendCLI) printAndLogError(args ...interface{}) {
 func (f *frontendCLI) processAPIError(err error) {
 	log.Warn("API error: ", err)
 	switch err {
-	case pmapi.ErrAPINotReachable:
+	case pmapi.ErrNoConnection:
 		f.notifyInternetOff()
 	case pmapi.ErrUpgradeApplication:
 		f.notifyNeedUpgrade()

internal/frontend/cli/accounts.go

@@ -18,6 +18,7 @@
 package cli
 
 import (
+	"context"
 	"strings"
 
 	"github.com/ProtonMail/proton-bridge/internal/bridge"
@@ -28,7 +29,7 @@ import (
 
 func (f *frontendCLI) listAccounts(c *ishell.Context) {
 	spacing := "%-2d: %-20s (%-15s, %-15s)\n"
-	f.Printf(bold(strings.Replace(spacing, "d", "s", -1)), "#", "account", "status", "address mode")
+	f.Printf(bold(strings.ReplaceAll(spacing, "d", "s")), "#", "account", "status", "address mode")
 	for idx, user := range f.bridge.GetUsers() {
 		connected := "disconnected"
 		if user.IsConnected() {
@@ -126,7 +127,7 @@ func (f *frontendCLI) loginAccount(c *ishell.Context) { // nolint[funlen]
 			return
 		}
 
-		err = client.Auth2FA(twoFactor, auth)
+		err = client.Auth2FA(context.Background(), twoFactor)
 		if err != nil {
 			f.processAPIError(err)
 			return

internal/frontend/cli/frontend.go

@@ -157,15 +157,6 @@ func New( //nolint[funlen]
 	})
 	fe.AddCmd(updatesCmd)
 
-	// Check commands.
-	checkCmd := &ishell.Cmd{Name: "check", Help: "check internet connection or new version."}
-	checkCmd.AddCmd(&ishell.Cmd{Name: "internet",
-		Help:    "check internet connection. (aliases: i, conn, connection)",
-		Aliases: []string{"i", "con", "connection"},
-		Func:    fe.checkInternetConnection,
-	})
-	fe.AddCmd(checkCmd)
-
 	// Print info commands.
 	fe.AddCmd(&ishell.Cmd{Name: "log-dir",
 		Help:    "print path to directory with logs. (aliases: log, logs)",
@@ -228,14 +219,14 @@ func New( //nolint[funlen]
 }
 
 func (f *frontendCLI) watchEvents() {
-	errorCh := f.getEventChannel(events.ErrorEvent)
+	errorCh := f.eventListener.ProvideChannel(events.ErrorEvent)
-	credentialsErrorCh := f.getEventChannel(events.CredentialsErrorEvent)
+	credentialsErrorCh := f.eventListener.ProvideChannel(events.CredentialsErrorEvent)
-	internetOffCh := f.getEventChannel(events.InternetOffEvent)
+	internetOffCh := f.eventListener.ProvideChannel(events.InternetOffEvent)
-	internetOnCh := f.getEventChannel(events.InternetOnEvent)
+	internetOnCh := f.eventListener.ProvideChannel(events.InternetOnEvent)
-	addressChangedCh := f.getEventChannel(events.AddressChangedEvent)
+	addressChangedCh := f.eventListener.ProvideChannel(events.AddressChangedEvent)
-	addressChangedLogoutCh := f.getEventChannel(events.AddressChangedLogoutEvent)
+	addressChangedLogoutCh := f.eventListener.ProvideChannel(events.AddressChangedLogoutEvent)
-	logoutCh := f.getEventChannel(events.LogoutEvent)
+	logoutCh := f.eventListener.ProvideChannel(events.LogoutEvent)
-	certIssue := f.getEventChannel(events.TLSCertIssue)
+	certIssue := f.eventListener.ProvideChannel(events.TLSCertIssue)
 	for {
 		select {
 		case errorDetails := <-errorCh:
@@ -262,13 +253,6 @@ func (f *frontendCLI) watchEvents() {
 	}
 }
 
-func (f *frontendCLI) getEventChannel(event string) <-chan string {
-	ch := make(chan string)
-	f.eventListener.Add(event, ch)
-	f.eventListener.RetryEmit(event)
-	return ch
-}
-
 // Loop starts the frontend loop with an interactive shell.
 func (f *frontendCLI) Loop() error {
 	f.Print(`

internal/frontend/cli/system.go

@@ -39,14 +39,6 @@ func (f *frontendCLI) restart(c *ishell.Context) {
 	}
 }
 
-func (f *frontendCLI) checkInternetConnection(c *ishell.Context) {
-	if f.bridge.CheckConnection() == nil {
-		f.Println("Internet connection is available.")
-	} else {
-		f.Println("Can not contact the server, please check your internet connection.")
-	}
-}
-
 func (f *frontendCLI) printLogDir(c *ishell.Context) {
 	if path, err := f.locations.ProvideLogsPath(); err != nil {
 		f.Println("Failed to determine location of log files")
@@ -161,7 +153,7 @@ func (f *frontendCLI) disallowProxy(c *ishell.Context) {
 }
 
 func (f *frontendCLI) isPortFree(port string) bool {
-	port = strings.Replace(port, ":", "", -1)
+	port = strings.ReplaceAll(port, ":", "")
 	if port == "" || port == currentPort {
 		return true
 	}

internal/frontend/cli/utils.go

@@ -71,7 +71,7 @@ func (f *frontendCLI) printAndLogError(args ...interface{}) {
 func (f *frontendCLI) processAPIError(err error) {
 	log.Warn("API error: ", err)
 	switch err {
-	case pmapi.ErrAPINotReachable:
+	case pmapi.ErrNoConnection:
 		f.notifyInternetOff()
 	case pmapi.ErrUpgradeApplication:
 		f.notifyNeedUpgrade()

internal/frontend/qml/GuiIE.qml

@@ -215,7 +215,7 @@ Item {
             }
             go.updateState = "updateRestart"
             winMain.dialogUpdate.finished(false)
-
+        
             // after manual update - just retart immidiatly
             go.setToRestart()
             Qt.quit()
@@ -236,13 +236,13 @@ Item {
             }
         }
 
-        onNotifySilentUpdateRestartNeeded: {
+        //onNotifySilentUpdateRestartNeeded: {
-            go.updateState = "updateRestart"
+        //    go.updateState = "updateRestart"
-        }
+        //}
-
+        //
-        onNotifySilentUpdateError: {
+        //onNotifySilentUpdateError: {
-            go.updateState = "updateError"
+        //    go.updateState = "updateError"
-        }
+        //}
 
         onNotifyLogout : {
             go.notifyBubble(0, qsTr("Account %1 has been disconnected. Please log in to continue to use the Import-Export app with this account.").arg(accname) )

internal/frontend/qml/ImportExportUI/AccountDelegate.qml

@@ -165,6 +165,7 @@ Column {
             textColor : Style.main.textBlue
             onClicked: {
                 dialogExport.currentIndex = 0
+                dialogExport.account = account
                 dialogExport.address = account
                 dialogExport.show()
             }
@@ -321,6 +322,7 @@ Column {
                         textBold: true
                         textColor: Style.main.textBlue
                         onClicked: {
+                            dialogExport.account = account
                             dialogExport.address = listalias[index]
                             dialogExport.show()
                         }
@@ -339,6 +341,7 @@ Column {
                         textBold: true
                         textColor: enabled ? Style.main.textBlue : Style.main.textDisabled
                         onClicked: {
+                            dialogImport.account = account
                             dialogImport.address = listalias[index]
                             dialogImport.show()
                         }

internal/frontend/qml/ImportExportUI/DialogExport.qml

@@ -35,6 +35,7 @@ Dialog {
 
     title : set_title()
 
+    property string account
     property string address
     property alias finish: finish
 
@@ -408,7 +409,6 @@ Dialog {
 
     onShow: {
         if (winMain.updateState==gui.enums.statusNoInternet) {
-            go.checkInternet()
             if (winMain.updateState==gui.enums.statusNoInternet) {
                 go.notifyError(gui.enums.errNoInternet)
                 root.hide()
@@ -428,7 +428,7 @@ Dialog {
         onTriggered : {
             switch (currentIndex) {
                 case 0:
-                go.loadStructureForExport(root.address)
+                go.loadStructureForExport(root.account, root.address)
                 sourceFoldersInput.hasItems = (transferRules.rowCount() > 0)
                 break
                 case 2:

internal/frontend/qml/ImportExportUI/DialogImport.qml

@@ -34,6 +34,7 @@ Dialog {
 
     isDialogBusy: currentIndex==3 || currentIndex==4
 
+    property string account
     property string address
     property string inputPath  : ""
     property bool   isFromFile : inputEmail.text == "" && root.inputPath != ""
@@ -856,14 +857,12 @@ Dialog {
                 inputPort     . checkIsANumber()
                 //emailProvider . currentIndex!=0
             )) isOK = false
-            go.checkInternet()
             if (winMain.updateState == gui.enums.statusNoInternet) { // todo: use main error dialog for this
                 errorPopup.show(qsTr("Please check your internet connection."))
                 return false
             }
             break
             case 2: // loading structure
-            go.checkInternet()
             if (winMain.updateState == gui.enums.statusNoInternet) {
                 errorPopup.show(qsTr("Please check your internet connection."))
                 return false
@@ -948,7 +947,6 @@ Dialog {
     onShow : {
         root.clear()
         if (winMain.updateState==gui.enums.statusNoInternet) {
-            go.checkInternet()
             if (winMain.updateState==gui.enums.statusNoInternet) {
                 winMain.popupMessage.show(go.canNotReachAPI)
                 root.hide()
@@ -1032,6 +1030,7 @@ Dialog {
                     root.isFromIMAP,
                     root.inputPath,
                     inputEmail.text, inputPassword.text, inputServer.text, inputPort.text,
+                    root.account,
                     root.address
                 )
                 break

internal/frontend/qml/ImportExportUI/SettingsView.qml

@@ -96,6 +96,8 @@ Item {
                 onClicked: bugreportWin.show()
             }
 
+            /*
+
             ButtonIconText {
                 id: autoUpdates
                 text: qsTr("Keep the application up to date", "label for toggle that activates and disables the automatic updates")
@@ -115,8 +117,6 @@ Item {
                 }
             }
 
-            /*
-
              ButtonIconText {
                  id: cacheClear
                  text: qsTr("Clear Cache")

internal/frontend/qml/ProtonUI/Dialog.qml

@@ -18,6 +18,7 @@
 // Dialog with adding new user
 
 import QtQuick 2.8
+import QtQuick.Controls 2.1
 import QtQuick.Layouts 1.3
 import ProtonUI 1.0
 
@@ -83,6 +84,9 @@ StackLayout {
             text : ""
             color: Style.main.textBlue
             visible: false
+            width: root.width
+            horizontalAlignment: Text.AlignHCenter
+            wrapMode: Text.WordWrap
         }
 
         // prevent any action below

internal/frontend/qml/ProtonUI/DialogAddUser.qml

@@ -70,7 +70,8 @@ Dialog {
             id: topSep
             color  : "transparent"
             width  : Style.main.dummy
-            height : root.height/2 - (dialogNameAndPassword.heightInputs)/2
+            // Hacky hack: +10 is to make title of Dialog bigger so longer error can fit just fine.
+            height : root.height/2 + 10 - (dialogNameAndPassword.heightInputs)/2
         }
 
         InputField {

internal/frontend/qml/ProtonUI/DialogUpdate.qml

@@ -107,7 +107,7 @@ Dialog {
                 text: qsTr("Automatically update in the future", "Checkbox label for using autoupdates later on")
                 checked: go.isAutoUpdate
                 onToggled: go.toggleAutoUpdate()
-                visible: !root.forceUpdate
+                visible: !root.forceUpdate && (go.isAutoUpdate != undefined)
             }
 
             Row {

internal/frontend/qml/ProtonUI/InformationBar.qml

@@ -25,33 +25,12 @@ import ProtonUI 1.0
 Rectangle {
     id: root
     property var iTry: 0
-    property var secLeft: 0
     property var second: 1000 // convert millisecond to second
-    property var checkInterval: [ 5, 10, 30, 60, 120, 300, 600 ] // seconds
     property bool isVisible: true
     property var fontSize : 1.2 * Style.main.fontSize
     color : "black"
     state: "upToDate"
 
-    Timer {
-        id: retryInternet
-        interval: second
-        triggeredOnStart: false
-        repeat: true
-        onTriggered : {
-            secLeft--
-            if (secLeft <= 0) {
-                retryInternet.stop()
-                go.checkInternet()
-                if (iTry < checkInterval.length-1) {
-                    iTry++
-                }
-                secLeft=checkInterval[iTry]
-                retryInternet.start()
-            }
-        }
-    }
-
     Row {
         id: messageRow
         anchors.centerIn: root
@@ -110,16 +89,12 @@ Rectangle {
             case "internetCheck":
                 break;
             case "noInternet" :
-                retryInternet.start()
-                secLeft=checkInterval[iTry]
                 break;
             case "oldVersion":
                 break;
             case "forceUpdate":
                 break;
             case "upToDate":
-                iTry = 0
-                secLeft=checkInterval[iTry]
                 break;
             case "updateRestart":
                 break;
@@ -128,24 +103,6 @@ Rectangle {
             default :
                 break;
         }
-
-        if (root.state!="noInternet") {
-            retryInternet.stop()
-        }
-    }
-
-    function timeToRetry() {
-        if (secLeft==1){
-            return qsTr("a second", "time to wait till internet connection is retried")
-        } else if (secLeft<60){
-            return secLeft + " " + qsTr("seconds", "time to wait till internet connection is retried")
-        } else {
-            var leading = ""+secLeft%60
-            if (leading.length < 2) {
-                leading = "0" + leading
-            }
-            return Math.floor(secLeft/60) + ":" + leading
-        }
     }
 
     states: [
@@ -194,23 +151,15 @@ Rectangle {
             PropertyChanges {
                 target: message
                 color: Style.main.line
-                text: qsTr("Cannot contact server. Retrying in ", "displayed when the app is disconnected from the internet or server has problems")+timeToRetry()+"."
+                text: qsTr("Cannot contact server. Please wait...", "displayed when the app is disconnected from the internet or server has problems")
             }
             PropertyChanges {
                 target: linkText
                 visible: false
             }
-            PropertyChanges {
-                target: actionText
-                visible: true
-                text: qsTr("Retry now", "click to try to connect to the internet when the app is disconnected from the internet")
-                onClicked: {
-                    go.checkInternet()
-                }
-            }
             PropertyChanges {
                 target: separatorText
-                visible: true
+                visible: false
                 text: "|"
             }
             PropertyChanges {

internal/frontend/qml/tst_GuiIE.qml

@@ -23,13 +23,13 @@ import QtQuick.Window 2.2
 
 Window {
     id      : testroot
-    width   : 100
+    width   : 150
     height  : 600
     flags   : Qt.Window | Qt.Dialog | Qt.FramelessWindowHint
     visible : true
     title   : "GUI test Window"
     color   : "transparent"
-    x       : testgui.winMain.x - 120
+    x       : testgui.winMain.x - 170
     y       : testgui.winMain.y
 
     property bool newVersion : true
@@ -110,8 +110,8 @@ Window {
         ListElement { title: "NotifyManualUpdateRestart" }
         ListElement { title: "NotifyManualUpdateError" }
         ListElement { title: "ForceUpdate" }
-        ListElement { title: "NotifySilentUpdateRestartNeeded" }
+        //ListElement { title: "NotifySilentUpdateRestartNeeded" }
-        ListElement { title: "NotifySilentUpdateError" }
+        //ListElement { title: "NotifySilentUpdateError" }
         ListElement { title : "ImportStructure"     }
         ListElement { title : "DraftImpFailed"      }
         ListElement { title : "NoInterImp"          }
@@ -183,12 +183,12 @@ Window {
                     case "ForceUpdate" :
                     go.notifyForceUpdate()
                     break;
-                    case "NotifySilentUpdateRestartNeeded" :
+                    //case "NotifySilentUpdateRestartNeeded" :
-                    go.notifySilentUpdateRestartNeeded()
+                    //go.notifySilentUpdateRestartNeeded()
-                    break;
+                    //break;
-                    case "NotifySilentUpdateError" :
+                    //case "NotifySilentUpdateError" :
-                    go.notifySilentUpdateError()
+                    //go.notifySilentUpdateError()
-                    break;
+                    //break;
                     case "ImportStructure" :
                     testgui.winMain.dialogImport.address = "cuto@pm.com"
                     testgui.winMain.dialogImport.show()
@@ -836,7 +836,7 @@ Window {
         id: go
 
         property int isAutoStart : 1
-        property bool isAutoUpdate : false
+        //property bool isAutoUpdate : false
         property bool isFirstStart : false
         property string currentAddress : "none"
         //property string goos : "windows"
@@ -858,15 +858,15 @@ Window {
 
         property string updateState
         property string updateVersion : "q0.1.0"
-        property bool updateCanInstall: true
+        property bool updateCanInstall: false
         property string updateLandingPage : "https://protonmail.com/import-export/download/"
         property string updateReleaseNotesLink  : "https://protonmail.com/download/ie/release_notes.html"
         signal notifyManualUpdate()
         signal notifyManualUpdateRestartNeeded()
         signal notifyManualUpdateError()
         signal notifyForceUpdate()
-        signal notifySilentUpdateRestartNeeded()
+        //signal notifySilentUpdateRestartNeeded()
-        signal notifySilentUpdateError()
+        //signal notifySilentUpdateError()
         function checkForUpdates() {
             console.log("checkForUpdates")
             go.notifyVersionIsTheLatest()
@@ -1331,10 +1331,6 @@ Window {
             return (fname!="fail")
         }
 
-        function checkInternet() {
-            // nothing to do
-        }
-
         function loadImportReports(fname) {
             console.log("load import reports for ", fname)
         }
@@ -1355,10 +1351,10 @@ Window {
             return !fname.includes("fail")
         }
 
-        onToggleAutoUpdate: {
+        //onToggleAutoUpdate: {
-            workAndClose()
+        //    workAndClose()
-            isAutoUpdate = (isAutoUpdate!=false) ? false : true
+        //    isAutoUpdate = (isAutoUpdate!=false) ? false : true
-            console.log (" Test: onToggleAutoUpdate "+isAutoUpdate)
+        //    console.log (" Test: onToggleAutoUpdate "+isAutoUpdate)
-        }
+        //}
     }
 }

internal/frontend/qt-common/accounts.go

@@ -20,6 +20,7 @@
 package qtcommon
 
 import (
+	"context"
 	"fmt"
 	"strings"
 	"sync"
@@ -164,7 +165,7 @@ func (a *Accounts) showLoginError(err error, scope string) bool {
 		return false
 	}
 	log.Warnf("%s: %v", scope, err)
-	if err == pmapi.ErrAPINotReachable {
+	if err == pmapi.ErrNoConnection {
 		a.qml.SetConnectionStatus(false)
 		SendNotification(a.qml, TabAccount, a.qml.CanNotReachAPI())
 		a.qml.ProcessFinished()
@@ -207,7 +208,7 @@ func (a *Accounts) Auth2FA(twoFacAuth string) int {
 	if a.auth == nil || a.authClient == nil {
 		err = fmt.Errorf("missing authentication in auth2FA %p %p", a.auth, a.authClient)
 	} else {
-		err = a.authClient.Auth2FA(twoFacAuth, a.auth)
+		err = a.authClient.Auth2FA(context.Background(), twoFacAuth)
 	}
 
 	if a.showLoginError(err, "auth2FA") {

internal/frontend/qt-common/common.go

@@ -113,10 +113,3 @@ type Listener interface {
 	Add(string, chan<- string)
 	RetryEmit(string)
 }
-
-func MakeAndRegisterEvent(eventListener Listener, event string) <-chan string {
-	ch := make(chan string)
-	eventListener.Add(event, ch)
-	eventListener.RetryEmit(event)
-	return ch
-}

internal/frontend/qt-ie/export.go

@@ -29,7 +29,7 @@ const (
 	TypeMBOX = "MBOX"
 )
 
-func (f *FrontendQt) LoadStructureForExport(addressOrID string) {
+func (f *FrontendQt) LoadStructureForExport(username, addressOrID string) {
 	errCode := errUnknownError
 	var err error
 	defer func() {
@@ -41,7 +41,7 @@ func (f *FrontendQt) LoadStructureForExport(addressOrID string) {
 		}
 	}()
 
-	if f.transfer, err = f.ie.GetEMLExporter(addressOrID, ""); err != nil {
+	if f.transfer, err = f.ie.GetEMLExporter(username, addressOrID, ""); err != nil {
 		// The only error can be problem to load PM user and address.
 		errCode = errPMLoadFailed
 		return

internal/frontend/qt-ie/frontend.go

@@ -135,24 +135,24 @@ func (f *FrontendQt) SetVersion(version updater.VersionInfo) {
 }
 
 func (f *FrontendQt) NotifySilentUpdateInstalled() {
-	f.Qml.NotifySilentUpdateRestartNeeded()
+	//f.Qml.NotifySilentUpdateRestartNeeded()
 }
 
 func (f *FrontendQt) NotifySilentUpdateError(err error) {
-	f.Qml.NotifySilentUpdateError()
+	//f.Qml.NotifySilentUpdateError()
 }
 
 func (f *FrontendQt) watchEvents() {
-	credentialsErrorCh := qtcommon.MakeAndRegisterEvent(f.eventListener, events.CredentialsErrorEvent)
+	credentialsErrorCh := f.eventListener.ProvideChannel(events.CredentialsErrorEvent)
-	internetOffCh := qtcommon.MakeAndRegisterEvent(f.eventListener, events.InternetOffEvent)
+	internetOffCh := f.eventListener.ProvideChannel(events.InternetOffEvent)
-	internetOnCh := qtcommon.MakeAndRegisterEvent(f.eventListener, events.InternetOnEvent)
+	internetOnCh := f.eventListener.ProvideChannel(events.InternetOnEvent)
-	secondInstanceCh := qtcommon.MakeAndRegisterEvent(f.eventListener, events.SecondInstanceEvent)
+	secondInstanceCh := f.eventListener.ProvideChannel(events.SecondInstanceEvent)
-	restartBridgeCh := qtcommon.MakeAndRegisterEvent(f.eventListener, events.RestartBridgeEvent)
+	restartBridgeCh := f.eventListener.ProvideChannel(events.RestartBridgeEvent)
-	addressChangedCh := qtcommon.MakeAndRegisterEvent(f.eventListener, events.AddressChangedEvent)
+	addressChangedCh := f.eventListener.ProvideChannel(events.AddressChangedEvent)
-	addressChangedLogoutCh := qtcommon.MakeAndRegisterEvent(f.eventListener, events.AddressChangedLogoutEvent)
+	addressChangedLogoutCh := f.eventListener.ProvideChannel(events.AddressChangedLogoutEvent)
-	logoutCh := qtcommon.MakeAndRegisterEvent(f.eventListener, events.LogoutEvent)
+	logoutCh := f.eventListener.ProvideChannel(events.LogoutEvent)
-	updateApplicationCh := qtcommon.MakeAndRegisterEvent(f.eventListener, events.UpgradeApplicationEvent)
+	updateApplicationCh := f.eventListener.ProvideChannel(events.UpgradeApplicationEvent)
-	newUserCh := qtcommon.MakeAndRegisterEvent(f.eventListener, events.UserRefreshEvent)
+	newUserCh := f.eventListener.ProvideChannel(events.UserRefreshEvent)
 	for {
 		select {
 		case <-credentialsErrorCh:
@@ -245,11 +245,11 @@ func (f *FrontendQt) QtExecute(Procedure func(*FrontendQt) error) error {
 	f.Qml.SetCredits(importexport.Credits)
 	f.Qml.SetFullversion(f.buildVersion)
 
-	if f.settings.GetBool(settings.AutoUpdateKey) {
+	//if f.settings.GetBool(settings.AutoUpdateKey) {
-		f.Qml.SetIsAutoUpdate(true)
+	//	f.Qml.SetIsAutoUpdate(true)
-	} else {
+	//} else {
-		f.Qml.SetIsAutoUpdate(false)
+	//	f.Qml.SetIsAutoUpdate(false)
-	}
+	//}
 
 	go func() {
 		defer f.panicHandler.HandlePanic()
@@ -339,22 +339,17 @@ func (f *FrontendQt) sendBug(description, emailClient, address string) bool {
 	return true
 }
 
-func (f *FrontendQt) toggleAutoUpdate() {
+//func (f *FrontendQt) toggleAutoUpdate() {
-	defer f.Qml.ProcessFinished()
+//	defer f.Qml.ProcessFinished()
-
+//
-	if f.settings.GetBool(settings.AutoUpdateKey) {
+//	if f.settings.GetBool(settings.AutoUpdateKey) {
-		f.settings.SetBool(settings.AutoUpdateKey, false)
+//		f.settings.SetBool(settings.AutoUpdateKey, false)
-		f.Qml.SetIsAutoUpdate(false)
+//		f.Qml.SetIsAutoUpdate(false)
-	} else {
+//	} else {
-		f.settings.SetBool(settings.AutoUpdateKey, true)
+//		f.settings.SetBool(settings.AutoUpdateKey, true)
-		f.Qml.SetIsAutoUpdate(true)
+//		f.Qml.SetIsAutoUpdate(true)
-	}
+//	}
-}
+//}
-
-// checkInternet is almost idetical to bridge
-func (f *FrontendQt) checkInternet() {
-	f.Qml.SetConnectionStatus(f.ie.CheckConnection() == nil)
-}
 
 func (f *FrontendQt) showError(code int, err error) {
 	f.Qml.SetErrorDescription(err.Error())

internal/frontend/qt-ie/import.go

@@ -26,7 +26,7 @@ import (
 )
 
 // wrapper for QML
-func (f *FrontendQt) setupAndLoadForImport(isFromIMAP bool, sourcePath, sourceEmail, sourcePassword, sourceServer, sourcePort, targetAddress string) {
+func (f *FrontendQt) setupAndLoadForImport(isFromIMAP bool, sourcePath, sourceEmail, sourcePassword, sourceServer, sourcePort, targetUsername, targetAddress string) {
 	errCode := errUnknownError
 	var err error
 	defer func() {
@@ -39,7 +39,7 @@ func (f *FrontendQt) setupAndLoadForImport(isFromIMAP bool, sourcePath, sourceEm
 	}()
 
 	if isFromIMAP {
-		f.transfer, err = f.ie.GetRemoteImporter(targetAddress, sourceEmail, sourcePassword, sourceServer, sourcePort)
+		f.transfer, err = f.ie.GetRemoteImporter(targetUsername, targetAddress, sourceEmail, sourcePassword, sourceServer, sourcePort)
 		if err != nil {
 			switch {
 			case errors.Is(err, &transfer.ErrIMAPConnection{}):
@@ -54,7 +54,7 @@ func (f *FrontendQt) setupAndLoadForImport(isFromIMAP bool, sourcePath, sourceEm
 			return
 		}
 	} else {
-		f.transfer, err = f.ie.GetLocalImporter(targetAddress, sourcePath)
+		f.transfer, err = f.ie.GetLocalImporter(targetUsername, targetAddress, sourcePath)
 		if err != nil {
 			// The only error can be problem to load PM user and address.
 			errCode = errPMLoadFailed

internal/frontend/qt-ie/ui.go

@@ -33,7 +33,7 @@ type GoQMLInterface struct {
 
 	_ func() `constructor:"init"`
 
-	_ bool   `property:"isAutoUpdate"`
+	//_ bool   `property:"isAutoUpdate"`
 	_ string `property:"currentAddress"`
 	_ string `property:"goos"`
 	_ string `property:"credits"`
@@ -62,8 +62,8 @@ type GoQMLInterface struct {
 	_ func() `signal:"notifyManualUpdateRestartNeeded"`
 	_ func() `signal:"notifyManualUpdateError"`
 	_ func() `signal:"notifyForceUpdate"`
-	_ func() `signal:"notifySilentUpdateRestartNeeded"`
+	//_ func() `signal:"notifySilentUpdateRestartNeeded"`
-	_ func() `signal:"notifySilentUpdateError"`
+	//_ func() `signal:"notifySilentUpdateError"`
 	_ func() `slot:"checkForUpdates"`
 	_ func() `slot:"checkAndOpenReleaseNotes"`
 	_ func() `signal:"openReleaseNotesExternally"`
@@ -77,8 +77,7 @@ type GoQMLInterface struct {
 	_ string `property:"credentialsNotRemoved"`
 	_ string `property:"versionCheckFailed"`
 	//
-	_ func(isAvailable bool)   `signal:"setConnectionStatus"`
+	_ func(isAvailable bool) `signal:"setConnectionStatus"`
-	_ func()                   `slot:"checkInternet"`
 
 	_ func() `slot:"setToRestart"`
 
@@ -93,7 +92,7 @@ type GoQMLInterface struct {
 
 	_ func() `signal:"showWindow"`
 
-	_ func() `slot:"toggleAutoUpdate"`
+	//_ func() `slot:"toggleAutoUpdate"`
 	_ func() `slot:"quit"`
 	_ func() `slot:"loadAccounts"`
 	_ func() `slot:"openLogs"`
@@ -108,14 +107,14 @@ type GoQMLInterface struct {
 
 	_ func(description, client, address string) bool                                       `slot:"sendBug"`
 	_ func(address string) bool                                                            `slot:"sendImportReport"`
-	_ func(address string)                                                                 `slot:"loadStructureForExport"`
+	_ func(username, address string)                                                       `slot:"loadStructureForExport"`
 	_ func() string                                                                        `slot:"leastUsedColor"`
 	_ func(username string, name string, color string, isLabel bool, sourceID string) bool `slot:"createLabelOrFolder"`
 	_ func(fpath, address, fileType string, attachEncryptedBody bool)                      `slot:"startExport"`
 	_ func(email string, importEncrypted bool)                                             `slot:"startImport"`
 	_ func()                                                                               `slot:"resetSource"`
 
-	_ func(isFromIMAP bool, sourcePath, sourceEmail, sourcePassword, sourceServe, sourcePort, targetAddress string) `slot:"setupAndLoadForImport"`
+	_ func(isFromIMAP bool, sourcePath, sourceEmail, sourcePassword, sourceServe, sourcePort, targetUsername, targetAddress string) `slot:"setupAndLoadForImport"`
 
 	_ string `property:"progressInit"`
 
@@ -162,7 +161,7 @@ func (s *GoQMLInterface) init() {}
 func (s *GoQMLInterface) SetFrontend(f *FrontendQt) {
 	s.ConnectQuit(f.App.Quit)
 
-	s.ConnectToggleAutoUpdate(f.toggleAutoUpdate)
+	//s.ConnectToggleAutoUpdate(f.toggleAutoUpdate)
 	s.ConnectLoadAccounts(f.Accounts.LoadAccounts)
 	s.ConnectOpenLogs(f.openLogs)
 	s.ConnectOpenDownloadLink(f.openDownloadLink)
@@ -189,8 +188,6 @@ func (s *GoQMLInterface) SetFrontend(f *FrontendQt) {
 		return f.programVersion
 	})
 
-	s.ConnectCheckInternet(f.checkInternet)
-
 	s.ConnectSetToRestart(f.restarter.SetToRestart)
 
 	s.ConnectLoadStructureForExport(f.LoadStructureForExport)
@@ -207,4 +204,6 @@ func (s *GoQMLInterface) SetFrontend(f *FrontendQt) {
 	s.ConnectCheckPathStatus(CheckPathStatus)
 
 	s.ConnectEmitEvent(f.emitEvent)
+
+	s.ConnectStartManualUpdate(f.startManualUpdate)
 }

internal/frontend/qt/accounts.go

@@ -20,6 +20,7 @@
 package qt
 
 import (
+	"context"
 	"fmt"
 	"strings"
 
@@ -130,7 +131,7 @@ func (s *FrontendQt) showLoginError(err error, scope string) bool {
 		return false
 	}
 	log.Warnf("%s: %v", scope, err)
-	if err == pmapi.ErrAPINotReachable {
+	if err == pmapi.ErrNoConnection {
 		s.Qml.SetConnectionStatus(false)
 		s.SendNotification(TabAccount, s.Qml.CanNotReachAPI())
 		s.Qml.ProcessFinished()
@@ -173,7 +174,7 @@ func (s *FrontendQt) auth2FA(twoFacAuth string) int {
 	if s.auth == nil || s.authClient == nil {
 		err = fmt.Errorf("missing authentication in auth2FA %p %p", s.auth, s.authClient)
 	} else {
-		err = s.authClient.Auth2FA(twoFacAuth, s.auth)
+		err = s.authClient.Auth2FA(context.Background(), twoFacAuth)
 	}
 
 	if s.showLoginError(err, "auth2FA") {

internal/frontend/qt/frontend.go

@@ -191,20 +191,20 @@ func (s *FrontendQt) NotifySilentUpdateError(err error) {
 func (s *FrontendQt) watchEvents() {
 	s.WaitUntilFrontendIsReady()
 
-	errorCh := s.getEventChannel(events.ErrorEvent)
+	errorCh := s.eventListener.ProvideChannel(events.ErrorEvent)
-	credentialsErrorCh := s.getEventChannel(events.CredentialsErrorEvent)
+	credentialsErrorCh := s.eventListener.ProvideChannel(events.CredentialsErrorEvent)
-	outgoingNoEncCh := s.getEventChannel(events.OutgoingNoEncEvent)
+	outgoingNoEncCh := s.eventListener.ProvideChannel(events.OutgoingNoEncEvent)
-	noActiveKeyForRecipientCh := s.getEventChannel(events.NoActiveKeyForRecipientEvent)
+	noActiveKeyForRecipientCh := s.eventListener.ProvideChannel(events.NoActiveKeyForRecipientEvent)
-	internetOffCh := s.getEventChannel(events.InternetOffEvent)
+	internetOffCh := s.eventListener.ProvideChannel(events.InternetOffEvent)
-	internetOnCh := s.getEventChannel(events.InternetOnEvent)
+	internetOnCh := s.eventListener.ProvideChannel(events.InternetOnEvent)
-	secondInstanceCh := s.getEventChannel(events.SecondInstanceEvent)
+	secondInstanceCh := s.eventListener.ProvideChannel(events.SecondInstanceEvent)
-	restartBridgeCh := s.getEventChannel(events.RestartBridgeEvent)
+	restartBridgeCh := s.eventListener.ProvideChannel(events.RestartBridgeEvent)
-	addressChangedCh := s.getEventChannel(events.AddressChangedEvent)
+	addressChangedCh := s.eventListener.ProvideChannel(events.AddressChangedEvent)
-	addressChangedLogoutCh := s.getEventChannel(events.AddressChangedLogoutEvent)
+	addressChangedLogoutCh := s.eventListener.ProvideChannel(events.AddressChangedLogoutEvent)
-	logoutCh := s.getEventChannel(events.LogoutEvent)
+	logoutCh := s.eventListener.ProvideChannel(events.LogoutEvent)
-	updateApplicationCh := s.getEventChannel(events.UpgradeApplicationEvent)
+	updateApplicationCh := s.eventListener.ProvideChannel(events.UpgradeApplicationEvent)
-	newUserCh := s.getEventChannel(events.UserRefreshEvent)
+	newUserCh := s.eventListener.ProvideChannel(events.UserRefreshEvent)
-	certIssue := s.getEventChannel(events.TLSCertIssue)
+	certIssue := s.eventListener.ProvideChannel(events.TLSCertIssue)
 	for {
 		select {
 		case errorDetails := <-errorCh:
@@ -254,13 +254,6 @@ func (s *FrontendQt) watchEvents() {
 	}
 }
 
-func (s *FrontendQt) getEventChannel(event string) <-chan string {
-	ch := make(chan string)
-	s.eventListener.Add(event, ch)
-	s.eventListener.RetryEmit(event)
-	return ch
-}
-
 // Loop function for tests.
 //
 // It runs QtExecute in new thread with function returning itself after setup.
@@ -370,24 +363,15 @@ func (s *FrontendQt) qtExecute(Procedure func(*FrontendQt) error) error {
 	}
 	s.Qml.SetIsAutoStart(s.autostart.IsEnabled())
 
-	if s.settings.GetBool(settings.AllowProxyKey) {
+	s.Qml.SetIsAutoUpdate(s.settings.GetBool(settings.AutoUpdateKey))
-		s.Qml.SetIsProxyAllowed(true)
+	s.Qml.SetIsProxyAllowed(s.settings.GetBool(settings.AllowProxyKey))
-	} else {
+	s.Qml.SetIsEarlyAccess(updater.UpdateChannel(s.settings.Get(settings.UpdateChannelKey)) == updater.EarlyChannel)
-		s.Qml.SetIsProxyAllowed(false)
-	}
-
-	if updater.UpdateChannel(s.settings.Get(settings.UpdateChannelKey)) == updater.EarlyChannel {
-		s.Qml.SetIsEarlyAccess(true)
-	} else {
-		s.Qml.SetIsEarlyAccess(false)
-	}
 
 	availableKeychain := []string{}
 	for chain := range keychain.Helpers {
 		availableKeychain = append(availableKeychain, chain)
 	}
 	s.Qml.SetAvailableKeychain(availableKeychain)
-
 	s.Qml.SetSelectedKeychain(s.settings.Get(settings.PreferredKeychainKey))
 
 	// Set reporting of outgoing email without encryption.
@@ -662,10 +646,6 @@ func (s *FrontendQt) isSMTPSTARTTLS() bool {
 	return !s.settings.GetBool(settings.SMTPSSLKey)
 }
 
-func (s *FrontendQt) checkInternet() {
-	s.Qml.SetConnectionStatus(s.bridge.CheckConnection() == nil)
-}
-
 func (s *FrontendQt) switchAddressModeUser(iAccount int) {
 	defer s.Qml.ProcessFinished()
 	userID := s.Accounts.get(iAccount).UserID()

internal/frontend/qt/ui.go

@@ -84,7 +84,6 @@ type GoQMLInterface struct {
 	_ string  `property:"progressDescription"`
 
 	_ func(isAvailable bool) `signal:"setConnectionStatus"`
-	_ func()                 `slot:"checkInternet"`
 
 	_ func() `slot:"setToRestart"`
 
@@ -205,8 +204,6 @@ func (s *GoQMLInterface) SetFrontend(f *FrontendQt) {
 		return f.programVer
 	})
 
-	s.ConnectCheckInternet(f.checkInternet)
-
 	s.ConnectSetToRestart(f.restarter.SetToRestart)
 
 	s.ConnectToggleIsReportingOutgoingNoEnc(f.toggleIsReportingOutgoingNoEnc)

internal/frontend/share/icon.rc

@@ -1 +0,0 @@
-IDI_ICON1 ICON DISCARDABLE "logo.ico"

internal/frontend/share/info.rc

@@ -0,0 +1,45 @@
+#define STRINGIZE_(x) #x
+#define STRINGIZE(x) STRINGIZE_(x)
+
+IDI_ICON1 ICON DISCARDABLE STRINGIZE(ICO_FILE)
+
+#if defined BUILD_BRIDGE
+    #define FILE_COMMENTS "The Bridge is an application that runs on your computer in the background and seamlessly encrypts and decrypts your mail as it enters and leaves your computer."
+    #define FILE_DESCRIPTION "ProtonMail Bridge"
+    #define INTERNAL_NAME STRINGIZE(EXE_NAME)
+    #define PRODUCT_NAME "ProtonMail Bridge for Windows"
+#elif defined BUILD_IE
+    #define FILE_COMMENTS "The Import-Export app helps you to migrate your emails from local files or remote IMAP servers to ProtonMail or simply export emails to local folder."
+    #define FILE_DESCRIPTION "ProtonMail Import-Export app"
+    #define INTERNAL_NAME STRINGIZE(EXE_NAME)
+    #define PRODUCT_NAME "ProtonMail Import-Export app for Windows"
+#else
+    #error No target specified
+#endif
+
+#define LEGAL_COPYRIGHT "(C) " STRINGIZE(YEAR) " Proton Technologies AG"
+
+1 VERSIONINFO
+FILEVERSION     FILE_VERSION_COMMA,0
+PRODUCTVERSION  FILE_VERSION_COMMA,0
+BEGIN
+    BLOCK "StringFileInfo"
+    BEGIN
+        BLOCK "040904b0"
+        BEGIN
+            VALUE "Comments", FILE_COMMENTS
+            VALUE "CompanyName", "Proton Technologies AG"
+            VALUE "FileDescription", FILE_DESCRIPTION
+            VALUE "FileVersion", STRINGIZE(FILE_VERSION)
+            VALUE "InternalName", INTERNAL_NAME
+            VALUE "LegalCopyright", LEGAL_COPYRIGHT
+            VALUE "OriginalFilename", STRINGIZE(ORIGINAL_FILE_NAME)
+            VALUE "ProductName", PRODUCT_NAME
+            VALUE "ProductVersion", STRINGIZE(PRODUCT_VERSION)
+        END
+    END
+    BLOCK "VarFileInfo"
+    BEGIN
+        VALUE "Translation", 0x0409, 0x04B0
+    END
+END

internal/frontend/types/types.go

@@ -55,7 +55,6 @@ type UserManager interface {
 	GetUser(query string) (User, error)
 	DeleteUser(userID string, clearCache bool) error
 	ClearData() error
-	CheckConnection() error
 }
 
 // User is an interface of user needed by frontend.
@@ -114,10 +113,10 @@ func (b *bridgeWrap) GetUser(query string) (User, error) {
 type ImportExporter interface {
 	UserManager
 
-	GetLocalImporter(string, string) (*transfer.Transfer, error)
+	GetLocalImporter(string, string, string) (*transfer.Transfer, error)
-	GetRemoteImporter(string, string, string, string, string) (*transfer.Transfer, error)
+	GetRemoteImporter(string, string, string, string, string, string) (*transfer.Transfer, error)
-	GetEMLExporter(string, string) (*transfer.Transfer, error)
+	GetEMLExporter(string, string, string) (*transfer.Transfer, error)
-	GetMBOXExporter(string, string) (*transfer.Transfer, error)
+	GetMBOXExporter(string, string, string) (*transfer.Transfer, error)
 	ReportBug(osType, osVersion, description, accountName, address, emailClient string) error
 	ReportFile(osType, osVersion, accountName, address string, logdata []byte) error
 }

internal/imap/backend.go

@@ -16,6 +16,19 @@
 // along with ProtonMail Bridge.  If not, see <https://www.gnu.org/licenses/>.
 
 // Package imap provides IMAP server of the Bridge.
+//
+// Methods are called by the go-imap library in parallel.
+// Additional parallelism is achieved while handling each IMAP request.
+//
+// For example, ListMessages internally uses `fetchWorkers` workers to resolve each requested item.
+// When IMAP clients request message literals (or parts thereof), we sometimes need to build RFC822 message literals.
+// To do this, we pass build jobs to the message builder, which internally manages its own parallelism.
+// Summary:
+//  - each IMAP fetch request is handled in parallel,
+//  - within each IMAP fetch request, individual items are handled by a pool of `fetchWorkers` workers,
+//  - within each worker, build jobs are posted to the message builder,
+//  - the message builder handles build jobs using its own, independent worker pool,
+// The builder will handle jobs in parallel up to its own internal limit. This prevents it from overwhelming API.
 package imap
 
 import (
@@ -26,10 +39,19 @@ import (
 	"github.com/ProtonMail/proton-bridge/internal/bridge"
 	"github.com/ProtonMail/proton-bridge/internal/events"
 	"github.com/ProtonMail/proton-bridge/pkg/listener"
+	"github.com/ProtonMail/proton-bridge/pkg/message"
 	"github.com/emersion/go-imap"
 	goIMAPBackend "github.com/emersion/go-imap/backend"
 )
 
+const (
+	// NOTE: Each fetch worker has its own set of attach workers so there can be up to 20*5=100 API requests at once.
+	// This is a reasonable limit to not overwhelm API while still maintaining as much parallelism as possible.
+	fetchWorkers  = 20 // In how many workers to fetch message (group list on IMAP).
+	attachWorkers = 5  // In how many workers to fetch attachments (for one message).
+	buildWorkers  = 20 // In how many workers to build messages.
+)
+
 type panicHandler interface {
 	HandlePanic()
 }
@@ -43,6 +65,8 @@ type imapBackend struct {
 	users       map[string]*imapUser
 	usersLocker sync.Locker
 
+	builder *message.Builder
+
 	imapCache     map[string]map[string]string
 	imapCachePath string
 	imapCacheLock *sync.RWMutex
@@ -78,6 +102,8 @@ func newIMAPBackend(
 		users:       map[string]*imapUser{},
 		usersLocker: &sync.Mutex{},
 
+		builder: message.NewBuilder(fetchWorkers, attachWorkers, buildWorkers),
+
 		imapCachePath: cache.GetIMAPCachePath(),
 		imapCacheLock: &sync.RWMutex{},
 	}

internal/imap/bridge.go

@@ -38,11 +38,10 @@ type bridgeUser interface {
 	IsCombinedAddressMode() bool
 	GetAddressID(address string) (string, error)
 	GetPrimaryAddress() string
-	UpdateUser() error
 	Logout() error
 	CloseConnection(address string)
 	GetStore() storeUserProvider
-	GetTemporaryPMAPIClient() pmapi.Client
+	GetClient() pmapi.Client
 }
 
 type bridgeWrap struct {
@@ -61,7 +60,7 @@ func (b *bridgeWrap) GetUser(query string) (bridgeUser, error) {
 	if err != nil {
 		return nil, err
 	}
-	return newBridgeUserWrap(user), nil
+	return newBridgeUserWrap(user), nil //nolint[typecheck] missing methods are inherited
 }
 
 type bridgeUserWrap struct {
@@ -77,5 +76,5 @@ func (u *bridgeUserWrap) GetStore() storeUserProvider {
 	if store == nil {
 		return nil
 	}
-	return newStoreUserWrap(store)
+	return newStoreUserWrap(store) //nolint[typecheck] missing methods are inherited
 }

internal/imap/id/extension.go

@@ -26,7 +26,7 @@ type currentClientSetter interface {
 	SetClient(name, version string)
 }
 
-// Extension for IMAP server
+// Extension for IMAP server.
 type extension struct {
 	extID        imapserver.ConnExtension
 	clientSetter currentClientSetter

internal/imap/imap.go

@@ -19,11 +19,4 @@ package imap
 
 import "github.com/sirupsen/logrus"
 
-const (
+var log = logrus.WithField("pkg", "imap") //nolint[gochecknoglobals]
-	fetchMessagesWorkers    = 5 // In how many workers to fetch message (group list on IMAP).
-	fetchAttachmentsWorkers = 5 // In how many workers to fetch attachments (for one message).
-)
-
-var (
-	log = logrus.WithField("pkg", "imap") //nolint[gochecknoglobals]
-)

internal/imap/mailbox.go

@@ -37,10 +37,12 @@ type imapMailbox struct {
 	storeUser    storeUserProvider
 	storeAddress storeAddressProvider
 	storeMailbox storeMailboxProvider
+
+	builder *message.Builder
 }
 
 // newIMAPMailbox returns struct implementing go-imap/mailbox interface.
-func newIMAPMailbox(panicHandler panicHandler, user *imapUser, storeMailbox storeMailboxProvider) *imapMailbox {
+func newIMAPMailbox(panicHandler panicHandler, user *imapUser, storeMailbox storeMailboxProvider, builder *message.Builder) *imapMailbox {
 	return &imapMailbox{
 		panicHandler: panicHandler,
 		user:         user,
@@ -54,6 +56,8 @@ func newIMAPMailbox(panicHandler panicHandler, user *imapUser, storeMailbox stor
 		storeUser:    user.storeUser,
 		storeAddress: user.storeAddress,
 		storeMailbox: storeMailbox,
+
+		builder: builder,
 	}
 }
 

internal/imap/mailbox_append.go

@@ -0,0 +1,198 @@
+// Copyright (c) 2021 Proton Technologies AG
+//
+// This file is part of ProtonMail Bridge.
+//
+// ProtonMail Bridge is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// ProtonMail Bridge is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with ProtonMail Bridge.  If not, see <https://www.gnu.org/licenses/>.
+
+package imap
+
+import (
+	"io"
+	"net/mail"
+	"strings"
+	"time"
+
+	"github.com/ProtonMail/gopenpgp/v2/crypto"
+	"github.com/ProtonMail/proton-bridge/internal/imap/uidplus"
+	"github.com/ProtonMail/proton-bridge/pkg/message"
+	"github.com/ProtonMail/proton-bridge/pkg/pmapi"
+	"github.com/emersion/go-imap"
+	"github.com/pkg/errors"
+)
+
+// CreateMessage appends a new message to this mailbox. The \Recent flag will
+// be added regardless of whether flags is empty or not. If date is nil, the
+// current time will be used.
+//
+// If the Backend implements Updater, it must notify the client immediately
+// via a mailbox update.
+func (im *imapMailbox) CreateMessage(flags []string, date time.Time, body imap.Literal) error {
+	return im.logCommand(func() error {
+		return im.createMessage(flags, date, body)
+	}, "APPEND", flags, date)
+}
+
+func (im *imapMailbox) createMessage(flags []string, date time.Time, body imap.Literal) error { //nolint[funlen]
+	// Called from go-imap in goroutines - we need to handle panics for each function.
+	defer im.panicHandler.HandlePanic()
+
+	m, _, _, readers, err := message.Parse(body)
+	if err != nil {
+		return err
+	}
+
+	addr := im.storeAddress.APIAddress()
+	if addr == nil {
+		return errors.New("no available address for encryption")
+	}
+	m.AddressID = addr.ID
+
+	kr, err := im.user.client().KeyRingForAddressID(addr.ID)
+	if err != nil {
+		return err
+	}
+
+	// Handle imported messages which have no "Sender" address.
+	// This sometimes occurs with outlook which reports errors as imported emails or for drafts.
+	if m.Sender == nil {
+		im.log.Warning("Append: Missing email sender. Will use main address")
+		m.Sender = &mail.Address{
+			Name:    "",
+			Address: addr.Email,
+		}
+	}
+
+	// "Drafts" needs to call special API routes.
+	// Clients always append the whole message again and remove the old one.
+	if im.storeMailbox.LabelID() == pmapi.DraftLabel {
+		// Sender address needs to be sanitised (drafts need to match cases exactly).
+		m.Sender.Address = pmapi.ConstructAddress(m.Sender.Address, addr.Email)
+
+		draft, _, err := im.user.storeUser.CreateDraft(kr, m, readers, "", "", "")
+		if err != nil {
+			return errors.Wrap(err, "failed to create draft")
+		}
+
+		targetSeq := im.storeMailbox.GetUIDList([]string{draft.ID})
+		return uidplus.AppendResponse(im.storeMailbox.UIDValidity(), targetSeq)
+	}
+
+	// We need to make sure this is an import, and not a sent message from this account
+	// (sent messages from the account will be added by the event loop).
+	if im.storeMailbox.LabelID() == pmapi.SentLabel {
+		sanitizedSender := pmapi.SanitizeEmail(m.Sender.Address)
+
+		// Check whether this message was sent by a bridge user.
+		user, err := im.user.backend.bridge.GetUser(sanitizedSender)
+		if err == nil && user.ID() == im.storeUser.UserID() {
+			logEntry := im.log.WithField("addr", sanitizedSender).WithField("extID", m.Header.Get("Message-Id"))
+
+			// If we find the message in the store already, we can skip importing it.
+			if foundUID := im.storeMailbox.GetUIDByHeader(&m.Header); foundUID != uint32(0) {
+				logEntry.Info("Ignoring APPEND of duplicate to Sent folder")
+				return uidplus.AppendResponse(im.storeMailbox.UIDValidity(), &uidplus.OrderedSeq{foundUID})
+			}
+
+			// We didn't find the message in the store, so we are currently sending it.
+			logEntry.WithField("time", date).Info("No matching UID, continuing APPEND to Sent")
+		}
+	}
+
+	message.ParseFlags(m, flags)
+	if !date.IsZero() {
+		m.Time = date.Unix()
+	}
+
+	internalID := m.Header.Get("X-Pm-Internal-Id")
+	references := m.Header.Get("References")
+	referenceList := strings.Fields(references)
+
+	// In case there is a mail client which corrupts headers, try
+	// "References" too.
+	if internalID == "" && len(referenceList) > 0 {
+		lastReference := referenceList[len(referenceList)-1]
+		match := pmapi.RxInternalReferenceFormat.FindStringSubmatch(lastReference)
+		if len(match) == 2 {
+			internalID = match[1]
+		}
+	}
+
+	im.user.appendExpungeLock.Lock()
+	defer im.user.appendExpungeLock.Unlock()
+
+	// Avoid appending a message which is already on the server. Apply the
+	// new label instead. This always happens with Outlook (it uses APPEND
+	// instead of COPY).
+	if internalID != "" {
+		// Check to see if this belongs to a different address in split mode or another ProtonMail account.
+		msg, err := im.storeMailbox.GetMessage(internalID)
+		if err == nil && (im.user.user.IsCombinedAddressMode() || (im.storeAddress.AddressID() == msg.Message().AddressID)) {
+			IDs := []string{internalID}
+
+			// See the comment bellow.
+			if msg.IsMarkedDeleted() {
+				if err := im.storeMailbox.MarkMessagesUndeleted(IDs); err != nil {
+					log.WithError(err).Error("Failed to undelete re-imported internal message")
+				}
+			}
+
+			err = im.storeMailbox.LabelMessages(IDs)
+			if err != nil {
+				return err
+			}
+
+			targetSeq := im.storeMailbox.GetUIDList(IDs)
+			return uidplus.AppendResponse(im.storeMailbox.UIDValidity(), targetSeq)
+		}
+	}
+
+	im.log.Info("Importing external message")
+	if err := im.importMessage(m, readers, kr); err != nil {
+		im.log.Error("Import failed: ", err)
+		return err
+	}
+
+	// IMAP clients can move message to local folder (setting \Deleted flag)
+	// and then move it back (IMAP client does not remember the message,
+	// so instead removing the flag it imports duplicate message).
+	// Regular IMAP server would keep the message twice and later EXPUNGE would
+	// not delete the message (EXPUNGE would delete the original message and
+	// the new duplicate one would stay). API detects duplicates; therefore
+	// we need to remove \Deleted flag if IMAP client re-imports.
+	msg, err := im.storeMailbox.GetMessage(m.ID)
+	if err == nil && msg.IsMarkedDeleted() {
+		if err := im.storeMailbox.MarkMessagesUndeleted([]string{m.ID}); err != nil {
+			log.WithError(err).Error("Failed to undelete re-imported message")
+		}
+	}
+
+	targetSeq := im.storeMailbox.GetUIDList([]string{m.ID})
+	return uidplus.AppendResponse(im.storeMailbox.UIDValidity(), targetSeq)
+}
+
+func (im *imapMailbox) importMessage(m *pmapi.Message, readers []io.Reader, kr *crypto.KeyRing) (err error) {
+	body, err := message.BuildEncrypted(m, readers, kr)
+	if err != nil {
+		return err
+	}
+
+	labels := []string{}
+	for _, l := range m.LabelIDs {
+		if l == pmapi.StarredLabel {
+			labels = append(labels, pmapi.StarredLabel)
+		}
+	}
+
+	return im.storeMailbox.ImportMessage(m, body, labels)
+}

internal/imap/mailbox_fetch.go

@@ -0,0 +1,322 @@
+// Copyright (c) 2021 Proton Technologies AG
+//
+// This file is part of ProtonMail Bridge.
+//
+// ProtonMail Bridge is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// ProtonMail Bridge is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with ProtonMail Bridge.  If not, see <https://www.gnu.org/licenses/>.
+
+package imap
+
+import (
+	"bytes"
+	"context"
+
+	"github.com/ProtonMail/proton-bridge/internal/imap/cache"
+	"github.com/ProtonMail/proton-bridge/pkg/message"
+	"github.com/ProtonMail/proton-bridge/pkg/pmapi"
+	"github.com/emersion/go-imap"
+	"github.com/pkg/errors"
+	"github.com/sirupsen/logrus"
+)
+
+func (im *imapMailbox) getMessage(
+	storeMessage storeMessageProvider,
+	items []imap.FetchItem,
+	msgBuildCountHistogram *msgBuildCountHistogram,
+) (msg *imap.Message, err error) {
+	msglog := im.log.WithField("msgID", storeMessage.ID())
+	msglog.Trace("Getting message")
+
+	seqNum, err := storeMessage.SequenceNumber()
+	if err != nil {
+		return
+	}
+
+	m := storeMessage.Message()
+
+	msg = imap.NewMessage(seqNum, items)
+	for _, item := range items {
+		switch item {
+		case imap.FetchEnvelope:
+			// No need to check IsFullHeaderCached here. API header
+			// contain enough information to build the envelope.
+			msg.Envelope = message.GetEnvelope(m, storeMessage.GetMIMEHeader())
+		case imap.FetchBody, imap.FetchBodyStructure:
+			structure, err := im.getBodyStructure(storeMessage)
+			if err != nil {
+				return nil, err
+			}
+			if msg.BodyStructure, err = structure.IMAPBodyStructure([]int{}); err != nil {
+				return nil, err
+			}
+		case imap.FetchFlags:
+			msg.Flags = message.GetFlags(m)
+			if storeMessage.IsMarkedDeleted() {
+				msg.Flags = append(msg.Flags, imap.DeletedFlag)
+			}
+		case imap.FetchInternalDate:
+			// Apple Mail crashes fetching messages with date older than 1970.
+			// There is no point having message older than RFC itself, it's not possible.
+			msg.InternalDate = message.SanitizeMessageDate(m.Time)
+		case imap.FetchRFC822Size:
+			if msg.Size, err = im.getSize(storeMessage); err != nil {
+				return nil, err
+			}
+		case imap.FetchUid:
+			if msg.Uid, err = storeMessage.UID(); err != nil {
+				return nil, err
+			}
+		case imap.FetchAll, imap.FetchFast, imap.FetchFull, imap.FetchRFC822, imap.FetchRFC822Header, imap.FetchRFC822Text:
+			fallthrough // this is list of defined items by go-imap, but items can be also sections generated from requests
+		default:
+			if err = im.getLiteralForSection(item, msg, storeMessage, msgBuildCountHistogram); err != nil {
+				return
+			}
+		}
+	}
+
+	return msg, err
+}
+
+// getSize returns cached size or it will build the message, save the size in
+// DB and then returns the size after build.
+//
+// We are storing size in DB as part of pmapi messages metada. The size
+// attribute on the server represents size of encrypted body. The value is
+// cleared in Bridge and the final decrypted size (including header, attachment
+// and MIME structure) is computed after building the message.
+func (im *imapMailbox) getSize(storeMessage storeMessageProvider) (uint32, error) {
+	m := storeMessage.Message()
+	if m.Size <= 0 {
+		im.log.WithField("msgID", m.ID).Debug("Size unknown - downloading body")
+		// We are sure the size is not a problem right now. Clients
+		// might not first check sizes of all messages so we couldn't
+		// be sure if seeing 1st or 2nd sync is all right or not.
+		// Therefore, it's better to exclude getting size from the
+		// counting and see build count as real message build.
+		if _, _, err := im.getBodyAndStructure(storeMessage, nil); err != nil {
+			return 0, err
+		}
+	}
+	return uint32(m.Size), nil
+}
+
+func (im *imapMailbox) getLiteralForSection(
+	itemSection imap.FetchItem,
+	msg *imap.Message,
+	storeMessage storeMessageProvider,
+	msgBuildCountHistogram *msgBuildCountHistogram,
+) error {
+	section, err := imap.ParseBodySectionName(itemSection)
+	if err != nil {
+		log.WithError(err).Warn("Failed to parse body section name; part will be skipped")
+		return nil //nolint[nilerr] ignore error
+	}
+
+	var literal imap.Literal
+	if literal, err = im.getMessageBodySection(storeMessage, section, msgBuildCountHistogram); err != nil {
+		return err
+	}
+
+	msg.Body[section] = literal
+	return nil
+}
+
+// getBodyStructure returns the cached body structure or it will build the message,
+// save the structure in DB and then returns the structure after build.
+//
+// Apple Mail requests body structure for all messages irregularly. We cache
+// bodystructure in local database in order to not re-download all messages
+// from server.
+func (im *imapMailbox) getBodyStructure(storeMessage storeMessageProvider) (bs *message.BodyStructure, err error) {
+	bs, err = storeMessage.GetBodyStructure()
+	if err != nil {
+		im.log.WithError(err).Debug("Fail to retrieve bodystructure from database")
+	}
+	if bs == nil {
+		// We are sure the body structure is not a problem right now.
+		// Clients might do first fetch body structure so we couldn't
+		// be sure if seeing 1st or 2nd sync is all right or not.
+		// Therefore, it's better to exclude first body structure fetch
+		// from the counting and see build count as real message build.
+		if bs, _, err = im.getBodyAndStructure(storeMessage, nil); err != nil {
+			return
+		}
+	}
+	return
+}
+
+func (im *imapMailbox) getBodyAndStructure(
+	storeMessage storeMessageProvider, msgBuildCountHistogram *msgBuildCountHistogram,
+) (
+	structure *message.BodyStructure, bodyReader *bytes.Reader, err error,
+) {
+	m := storeMessage.Message()
+	id := im.storeUser.UserID() + m.ID
+	cache.BuildLock(id)
+	defer cache.BuildUnlock(id)
+	bodyReader, structure = cache.LoadMail(id)
+
+	// return the message which was found in cache
+	if bodyReader.Len() != 0 && structure != nil {
+		return structure, bodyReader, nil
+	}
+
+	structure, body, err := im.buildMessage(m)
+	bodyReader = bytes.NewReader(body)
+	size := int64(len(body))
+	l := im.log.WithField("newSize", size).WithField("msgID", m.ID)
+
+	if err != nil || structure == nil || size == 0 {
+		l.WithField("hasStructure", structure != nil).Warn("Failed to build message")
+		return structure, bodyReader, err
+	}
+
+	// Save the size, body structure and header even for messages which
+	// were unable to decrypt. Hence they doesn't have to be computed every
+	// time.
+	m.Size = size
+	cacheMessageInStore(storeMessage, structure, body, l)
+
+	if msgBuildCountHistogram != nil {
+		times, errCount := storeMessage.IncreaseBuildCount()
+		if errCount != nil {
+			l.WithError(errCount).Warn("Cannot increase build count")
+		}
+		msgBuildCountHistogram.add(times)
+	}
+
+	// Drafts can change therefore we don't want to cache them.
+	if !isMessageInDraftFolder(m) {
+		cache.SaveMail(id, body, structure)
+	}
+
+	return structure, bodyReader, err
+}
+
+func cacheMessageInStore(storeMessage storeMessageProvider, structure *message.BodyStructure, body []byte, l *logrus.Entry) {
+	m := storeMessage.Message()
+	if errSize := storeMessage.SetSize(m.Size); errSize != nil {
+		l.WithError(errSize).Warn("Cannot update size while building")
+	}
+	if structure != nil && !isMessageInDraftFolder(m) {
+		if errStruct := storeMessage.SetBodyStructure(structure); errStruct != nil {
+			l.WithError(errStruct).Warn("Cannot update bodystructure while building")
+		}
+	}
+	header, errHead := structure.GetMailHeaderBytes(bytes.NewReader(body))
+	if errHead == nil && len(header) != 0 {
+		if errStore := storeMessage.SetHeader(header); errStore != nil {
+			l.WithError(errStore).Warn("Cannot update header in store")
+		}
+	} else {
+		l.WithError(errHead).Warn("Cannot get header bytes from structure")
+	}
+}
+
+func isMessageInDraftFolder(m *pmapi.Message) bool {
+	for _, labelID := range m.LabelIDs {
+		if labelID == pmapi.DraftLabel {
+			return true
+		}
+	}
+	return false
+}
+
+// This will download message (or read from cache) and pick up the section,
+// extract data (header,body, both) and trim the output if needed.
+//
+// In order to speed up (avoid download and decryptions) we
+// cache the header. If a mail header was requested and DB
+// contains full header (it means it was already built once)
+// the DB header can be used without downloading and decrypting.
+// Otherwise header is incomplete and clients would have issues
+// e.g. AppleMail expects `text/plain` in HTML mails.
+//
+// For all other cases it is necessary to download and decrypt the message
+// and drop the header which was obtained from cache. The header will
+// will be stored in DB once successfully built. Check `getBodyAndStructure`.
+func (im *imapMailbox) getMessageBodySection(
+	storeMessage storeMessageProvider,
+	section *imap.BodySectionName,
+	msgBuildCountHistogram *msgBuildCountHistogram,
+) (imap.Literal, error) {
+	var header []byte
+	var response []byte
+
+	im.log.WithField("msgID", storeMessage.ID()).Trace("Getting message body")
+
+	isMainHeaderRequested := len(section.Path) == 0 && section.Specifier == imap.HeaderSpecifier
+	if isMainHeaderRequested && storeMessage.IsFullHeaderCached() {
+		header = storeMessage.GetHeader()
+	} else {
+		structure, bodyReader, err := im.getBodyAndStructure(storeMessage, msgBuildCountHistogram)
+		if err != nil {
+			return nil, err
+		}
+
+		switch {
+		case section.Specifier == imap.EntireSpecifier && len(section.Path) == 0:
+			//  An empty section specification refers to the entire message, including the header.
+			response, err = structure.GetSection(bodyReader, section.Path)
+		case section.Specifier == imap.TextSpecifier || (section.Specifier == imap.EntireSpecifier && len(section.Path) != 0):
+			// The TEXT specifier refers to the content of the message (or section), omitting the [RFC-2822] header.
+			// Non-empty section with no specifier (imap.EntireSpecifier) refers to section content without header.
+			response, err = structure.GetSectionContent(bodyReader, section.Path)
+		case section.Specifier == imap.MIMESpecifier: // The MIME part specifier refers to the [MIME-IMB] header for this part.
+			fallthrough
+		case section.Specifier == imap.HeaderSpecifier:
+			header, err = structure.GetSectionHeaderBytes(bodyReader, section.Path)
+		default:
+			err = errors.New("Unknown specifier " + string(section.Specifier))
+		}
+
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	if header != nil {
+		response = filterHeader(header, section)
+	}
+
+	// Trim any output if requested.
+	return bytes.NewBuffer(section.ExtractPartial(response)), nil
+}
+
+// buildMessage from PM to IMAP.
+func (im *imapMailbox) buildMessage(m *pmapi.Message) (*message.BodyStructure, []byte, error) {
+	body, err := im.builder.NewJobWithOptions(
+		context.Background(),
+		im.user.client(),
+		m.ID,
+		message.JobOptions{
+			IgnoreDecryptionErrors: true, // Whether to ignore decryption errors and create a "custom message" instead.
+			SanitizeDate:           true, // Whether to replace all dates before 1970 with RFC822's birthdate.
+			AddInternalID:          true, // Whether to include MessageID as X-Pm-Internal-Id.
+			AddExternalID:          true, // Whether to include ExternalID as X-Pm-External-Id.
+			AddMessageDate:         true, // Whether to include message time as X-Pm-Date.
+			AddMessageIDReference:  true, // Whether to include the MessageID in References.
+		},
+	).GetResult()
+	if err != nil {
+		return nil, nil, err
+	}
+
+	structure, err := message.NewBodyStructure(bytes.NewReader(body))
+	if err != nil {
+		return nil, nil, err
+	}
+
+	return structure, body, nil
+}

internal/imap/mailbox_fetch_test.go

@@ -0,0 +1,67 @@
+// Copyright (c) 2021 Proton Technologies AG
+//
+// This file is part of ProtonMail Bridge.
+//
+// ProtonMail Bridge is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// ProtonMail Bridge is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with ProtonMail Bridge.  If not, see <https://www.gnu.org/licenses/>.
+
+package imap
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestFilterHeader(t *testing.T) {
+	const header = "To: somebody\r\nFrom: somebody else\r\nSubject: this is\r\n\ta multiline field\r\n\r\n"
+
+	assert.Equal(t, "To: somebody\r\n\r\n", string(filterHeaderLines([]byte(header), func(field string) bool {
+		return strings.EqualFold(field, "To")
+	})))
+
+	assert.Equal(t, "From: somebody else\r\n\r\n", string(filterHeaderLines([]byte(header), func(field string) bool {
+		return strings.EqualFold(field, "From")
+	})))
+
+	assert.Equal(t, "To: somebody\r\nFrom: somebody else\r\n\r\n", string(filterHeaderLines([]byte(header), func(field string) bool {
+		return strings.EqualFold(field, "To") || strings.EqualFold(field, "From")
+	})))
+
+	assert.Equal(t, "Subject: this is\r\n\ta multiline field\r\n\r\n", string(filterHeaderLines([]byte(header), func(field string) bool {
+		return strings.EqualFold(field, "Subject")
+	})))
+}
+
+// TestFilterHeaderNoNewline tests that we don't include a trailing newline when filtering
+// if the original header also lacks one (which it can legally do if there is no body).
+func TestFilterHeaderNoNewline(t *testing.T) {
+	const header = "To: somebody\r\nFrom: somebody else\r\nSubject: this is\r\n\ta multiline field\r\n"
+
+	assert.Equal(t, "To: somebody\r\n", string(filterHeaderLines([]byte(header), func(field string) bool {
+		return strings.EqualFold(field, "To")
+	})))
+
+	assert.Equal(t, "From: somebody else\r\n", string(filterHeaderLines([]byte(header), func(field string) bool {
+		return strings.EqualFold(field, "From")
+	})))
+
+	assert.Equal(t, "To: somebody\r\nFrom: somebody else\r\n", string(filterHeaderLines([]byte(header), func(field string) bool {
+		return strings.EqualFold(field, "To") || strings.EqualFold(field, "From")
+	})))
+
+	assert.Equal(t, "Subject: this is\r\n\ta multiline field\r\n", string(filterHeaderLines([]byte(header), func(field string) bool {
+		return strings.EqualFold(field, "Subject")
+	})))
+}

internal/imap/mailbox_header.go

@@ -0,0 +1,104 @@
+// Copyright (c) 2021 Proton Technologies AG
+//
+// This file is part of ProtonMail Bridge.
+//
+// ProtonMail Bridge is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// ProtonMail Bridge is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with ProtonMail Bridge.  If not, see <https://www.gnu.org/licenses/>.
+
+package imap
+
+import (
+	"bufio"
+	"bytes"
+	"io"
+	"strings"
+
+	"github.com/emersion/go-imap"
+	"github.com/pkg/errors"
+)
+
+func filterHeader(header []byte, section *imap.BodySectionName) []byte {
+	// Empty section.Fields means BODY[HEADER] was requested so we should return the full header.
+	if len(section.Fields) == 0 {
+		return header
+	}
+
+	fieldMap := make(map[string]struct{})
+
+	for _, field := range section.Fields {
+		fieldMap[strings.ToLower(field)] = struct{}{}
+	}
+
+	return filterHeaderLines(header, func(field string) bool {
+		_, ok := fieldMap[strings.ToLower(field)]
+
+		if section.NotFields {
+			ok = !ok
+		}
+
+		return ok
+	})
+}
+
+func filterHeaderLines(header []byte, wantField func(string) bool) []byte {
+	var res []byte
+
+	for _, line := range headerLines(header) {
+		if len(bytes.TrimSpace(line)) == 0 {
+			res = append(res, line...)
+		} else {
+			split := bytes.SplitN(line, []byte(": "), 2)
+
+			if len(split) != 2 {
+				continue
+			}
+
+			if wantField(string(bytes.ToLower(split[0]))) {
+				res = append(res, line...)
+			}
+		}
+	}
+
+	return res
+}
+
+// NOTE: This sucks because we trim and split stuff here already, only to do it again when we use this function!
+func headerLines(header []byte) [][]byte {
+	var lines [][]byte
+
+	r := bufio.NewReader(bytes.NewReader(header))
+
+	for {
+		b, err := r.ReadBytes('\n')
+		if err != nil {
+			if err != io.EOF {
+				panic(errors.Wrap(err, "failed to read header line"))
+			}
+
+			break
+		}
+
+		switch {
+		case len(bytes.TrimSpace(b)) == 0:
+			lines = append(lines, b)
+
+		case len(bytes.SplitN(b, []byte(": "), 2)) != 2:
+			lines[len(lines)-1] = append(lines[len(lines)-1], b...)
+
+		default:
+			lines = append(lines, b)
+		}
+	}
+
+	return lines
+}

internal/imap/mailbox_message.go

@@ -1,790 +0,0 @@
-// Copyright (c) 2021 Proton Technologies AG
-//
-// This file is part of ProtonMail Bridge.
-//
-// ProtonMail Bridge is free software: you can redistribute it and/or modify
-// it under the terms of the GNU General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// ProtonMail Bridge is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU General Public License for more details.
-//
-// You should have received a copy of the GNU General Public License
-// along with ProtonMail Bridge.  If not, see <https://www.gnu.org/licenses/>.
-
-package imap
-
-import (
-	"bytes"
-	"fmt"
-	"io"
-	"mime/multipart"
-	"net/mail"
-	"net/textproto"
-	"sort"
-	"strings"
-	"time"
-
-	"github.com/ProtonMail/gopenpgp/v2/crypto"
-	"github.com/ProtonMail/proton-bridge/internal/imap/cache"
-	"github.com/ProtonMail/proton-bridge/internal/imap/uidplus"
-	"github.com/ProtonMail/proton-bridge/pkg/message"
-	"github.com/ProtonMail/proton-bridge/pkg/parallel"
-	"github.com/ProtonMail/proton-bridge/pkg/pmapi"
-	"github.com/emersion/go-imap"
-	"github.com/hashicorp/go-multierror"
-	"github.com/pkg/errors"
-	openpgperrors "golang.org/x/crypto/openpgp/errors"
-)
-
-var (
-	rfc822Birthday = time.Date(1982, 8, 13, 0, 0, 0, 0, time.UTC) //nolint[gochecknoglobals]
-)
-
-type doNotCacheError struct{ e error }
-
-func (dnc *doNotCacheError) Error() string { return dnc.e.Error() }
-func (dnc *doNotCacheError) add(err error) { dnc.e = multierror.Append(dnc.e, err) }
-func (dnc *doNotCacheError) errorOrNil() error {
-	if dnc == nil {
-		return nil
-	}
-
-	if dnc.e != nil {
-		return dnc
-	}
-
-	return nil
-}
-
-// CreateMessage appends a new message to this mailbox. The \Recent flag will
-// be added regardless of whether flags is empty or not. If date is nil, the
-// current time will be used.
-//
-// If the Backend implements Updater, it must notify the client immediately
-// via a mailbox update.
-func (im *imapMailbox) CreateMessage(flags []string, date time.Time, body imap.Literal) error {
-	return im.logCommand(func() error {
-		return im.createMessage(flags, date, body)
-	}, "APPEND", flags, date)
-}
-
-func (im *imapMailbox) createMessage(flags []string, date time.Time, body imap.Literal) error { // nolint[funlen]
-	// Called from go-imap in goroutines - we need to handle panics for each function.
-	defer im.panicHandler.HandlePanic()
-
-	m, _, _, readers, err := message.Parse(body)
-	if err != nil {
-		return err
-	}
-
-	addr := im.storeAddress.APIAddress()
-	if addr == nil {
-		return errors.New("no available address for encryption")
-	}
-	m.AddressID = addr.ID
-
-	kr, err := im.user.client().KeyRingForAddressID(addr.ID)
-	if err != nil {
-		return err
-	}
-
-	// Handle imported messages which have no "Sender" address.
-	// This sometimes occurs with outlook which reports errors as imported emails or for drafts.
-	if m.Sender == nil {
-		im.log.Warning("Append: Missing email sender. Will use main address")
-		m.Sender = &mail.Address{
-			Name:    "",
-			Address: addr.Email,
-		}
-	}
-
-	// "Drafts" needs to call special API routes.
-	// Clients always append the whole message again and remove the old one.
-	if im.storeMailbox.LabelID() == pmapi.DraftLabel {
-		// Sender address needs to be sanitised (drafts need to match cases exactly).
-		m.Sender.Address = pmapi.ConstructAddress(m.Sender.Address, addr.Email)
-
-		draft, _, err := im.user.storeUser.CreateDraft(kr, m, readers, "", "", "")
-		if err != nil {
-			return errors.Wrap(err, "failed to create draft")
-		}
-
-		targetSeq := im.storeMailbox.GetUIDList([]string{draft.ID})
-		return uidplus.AppendResponse(im.storeMailbox.UIDValidity(), targetSeq)
-	}
-
-	// We need to make sure this is an import, and not a sent message from this account
-	// (sent messages from the account will be added by the event loop).
-	if im.storeMailbox.LabelID() == pmapi.SentLabel {
-		sanitizedSender := pmapi.SanitizeEmail(m.Sender.Address)
-
-		// Check whether this message was sent by a bridge user.
-		user, err := im.user.backend.bridge.GetUser(sanitizedSender)
-		if err == nil && user.ID() == im.storeUser.UserID() {
-			logEntry := im.log.WithField("addr", sanitizedSender).WithField("extID", m.Header.Get("Message-Id"))
-
-			// If we find the message in the store already, we can skip importing it.
-			if foundUID := im.storeMailbox.GetUIDByHeader(&m.Header); foundUID != uint32(0) {
-				logEntry.Info("Ignoring APPEND of duplicate to Sent folder")
-				return uidplus.AppendResponse(im.storeMailbox.UIDValidity(), &uidplus.OrderedSeq{foundUID})
-			}
-
-			// We didn't find the message in the store, so we are currently sending it.
-			logEntry.WithField("time", date).Info("No matching UID, continuing APPEND to Sent")
-		}
-	}
-
-	message.ParseFlags(m, flags)
-	if !date.IsZero() {
-		m.Time = date.Unix()
-	}
-
-	internalID := m.Header.Get("X-Pm-Internal-Id")
-	references := m.Header.Get("References")
-	referenceList := strings.Fields(references)
-
-	// In case there is a mail client which corrupts headers, try
-	// "References" too.
-	if internalID == "" && len(referenceList) > 0 {
-		lastReference := referenceList[len(referenceList)-1]
-		match := pmapi.RxInternalReferenceFormat.FindStringSubmatch(lastReference)
-		if len(match) == 2 {
-			internalID = match[1]
-		}
-	}
-
-	im.user.appendExpungeLock.Lock()
-	defer im.user.appendExpungeLock.Unlock()
-
-	// Avoid appending a message which is already on the server. Apply the
-	// new label instead. This always happens with Outlook (it uses APPEND
-	// instead of COPY).
-	if internalID != "" {
-		// Check to see if this belongs to a different address in split mode or another ProtonMail account.
-		msg, err := im.storeMailbox.GetMessage(internalID)
-		if err == nil && (im.user.user.IsCombinedAddressMode() || (im.storeAddress.AddressID() == msg.Message().AddressID)) {
-			IDs := []string{internalID}
-
-			// See the comment bellow.
-			if msg.IsMarkedDeleted() {
-				if err := im.storeMailbox.MarkMessagesUndeleted(IDs); err != nil {
-					log.WithError(err).Error("Failed to undelete re-imported internal message")
-				}
-			}
-
-			err = im.storeMailbox.LabelMessages(IDs)
-			if err != nil {
-				return err
-			}
-
-			targetSeq := im.storeMailbox.GetUIDList([]string{m.ID})
-			return uidplus.AppendResponse(im.storeMailbox.UIDValidity(), targetSeq)
-		}
-	}
-
-	im.log.Info("Importing external message")
-	if err := im.importMessage(m, readers, kr); err != nil {
-		im.log.Error("Import failed: ", err)
-		return err
-	}
-
-	// IMAP clients can move message to local folder (setting \Deleted flag)
-	// and then move it back (IMAP client does not remember the message,
-	// so instead removing the flag it imports duplicate message).
-	// Regular IMAP server would keep the message twice and later EXPUNGE would
-	// not delete the message (EXPUNGE would delete the original message and
-	// the new duplicate one would stay). API detects duplicates; therefore
-	// we need to remove \Deleted flag if IMAP client re-imports.
-	msg, err := im.storeMailbox.GetMessage(m.ID)
-	if err == nil && msg.IsMarkedDeleted() {
-		if err := im.storeMailbox.MarkMessagesUndeleted([]string{m.ID}); err != nil {
-			log.WithError(err).Error("Failed to undelete re-imported message")
-		}
-	}
-
-	targetSeq := im.storeMailbox.GetUIDList([]string{m.ID})
-	return uidplus.AppendResponse(im.storeMailbox.UIDValidity(), targetSeq)
-}
-
-func (im *imapMailbox) importMessage(m *pmapi.Message, readers []io.Reader, kr *crypto.KeyRing) (err error) { // nolint[funlen]
-	body, err := message.BuildEncrypted(m, readers, kr)
-	if err != nil {
-		return err
-	}
-
-	labels := []string{}
-	for _, l := range m.LabelIDs {
-		if l == pmapi.StarredLabel {
-			labels = append(labels, pmapi.StarredLabel)
-		}
-	}
-
-	return im.storeMailbox.ImportMessage(m, body, labels)
-}
-
-func (im *imapMailbox) getMessage(storeMessage storeMessageProvider, items []imap.FetchItem) (msg *imap.Message, err error) {
-	im.log.WithField("msgID", storeMessage.ID()).Trace("Getting message")
-
-	seqNum, err := storeMessage.SequenceNumber()
-	if err != nil {
-		return
-	}
-
-	m := storeMessage.Message()
-
-	msg = imap.NewMessage(seqNum, items)
-	for _, item := range items {
-		switch item {
-		case imap.FetchEnvelope:
-			msg.Envelope = message.GetEnvelope(m)
-		case imap.FetchBody, imap.FetchBodyStructure:
-			var structure *message.BodyStructure
-			structure, err = im.getBodyStructure(storeMessage)
-			if err != nil {
-				return
-			}
-			if msg.BodyStructure, err = structure.IMAPBodyStructure([]int{}); err != nil {
-				return
-			}
-		case imap.FetchFlags:
-			msg.Flags = message.GetFlags(m)
-			if storeMessage.IsMarkedDeleted() {
-				msg.Flags = append(msg.Flags, imap.DeletedFlag)
-			}
-		case imap.FetchInternalDate:
-			msg.InternalDate = time.Unix(m.Time, 0)
-
-			// Apple Mail crashes fetching messages with date older than 1970.
-			// There is no point having message older than RFC itself, it's not possible.
-			if msg.InternalDate.Before(rfc822Birthday) {
-				msg.InternalDate = rfc822Birthday
-			}
-		case imap.FetchRFC822Size:
-			// Size attribute on the server counts encrypted data. The value is cleared
-			// on our part and we need to compute "real" size of decrypted data.
-			if m.Size <= 0 {
-				im.log.WithField("msgID", storeMessage.ID()).Trace("Size unknown - downloading body")
-				if _, _, err = im.getBodyAndStructure(storeMessage); err != nil {
-					return
-				}
-			}
-			msg.Size = uint32(m.Size)
-		case imap.FetchUid:
-			msg.Uid, err = storeMessage.UID()
-			if err != nil {
-				return nil, err
-			}
-		default:
-			if err = im.getLiteralForSection(item, msg, storeMessage); err != nil {
-				return
-			}
-		}
-	}
-
-	return msg, err
-}
-
-func (im *imapMailbox) getLiteralForSection(itemSection imap.FetchItem, msg *imap.Message, storeMessage storeMessageProvider) error {
-	section, err := imap.ParseBodySectionName(itemSection)
-	if err != nil { // Ignore error
-		return nil
-	}
-
-	var literal imap.Literal
-	if literal, err = im.getMessageBodySection(storeMessage, section); err != nil {
-		return err
-	}
-
-	msg.Body[section] = literal
-	return nil
-}
-
-func (im *imapMailbox) getBodyStructure(storeMessage storeMessageProvider) (bs *message.BodyStructure, err error) {
-	// Apple Mail requests body structure for all
-	// messages irregularly. We cache bodystructure in
-	// local database in order to not re-download all
-	// messages from server.
-	bs, err = storeMessage.GetBodyStructure()
-	if err != nil {
-		im.log.WithError(err).Debug("Fail to retrieve bodystructure from database")
-	}
-	if bs == nil {
-		if bs, _, err = im.getBodyAndStructure(storeMessage); err != nil {
-			return
-		}
-	}
-	return
-}
-
-func (im *imapMailbox) getBodyAndStructure(storeMessage storeMessageProvider) (
-	structure *message.BodyStructure,
-	bodyReader *bytes.Reader, err error,
-) {
-	m := storeMessage.Message()
-	id := im.storeUser.UserID() + m.ID
-	cache.BuildLock(id)
-	if bodyReader, structure = cache.LoadMail(id); bodyReader.Len() == 0 || structure == nil {
-		var body []byte
-		structure, body, err = im.buildMessage(m)
-		m.Size = int64(len(body))
-		// Save size and body structure even for messages unable to decrypt
-		// so the size or body structure doesn't have to be computed every time.
-		if err := storeMessage.SetSize(m.Size); err != nil {
-			im.log.WithError(err).
-				WithField("newSize", m.Size).
-				WithField("msgID", m.ID).
-				Warn("Cannot update size while building")
-		}
-		if structure != nil && !isMessageInDraftFolder(m) {
-			if err := storeMessage.SetBodyStructure(structure); err != nil {
-				im.log.WithError(err).
-					WithField("msgID", m.ID).
-					Warn("Cannot update bodystructure while building")
-			}
-		}
-		if err == nil && structure != nil && len(body) > 0 {
-			if err := storeMessage.SetContentTypeAndHeader(m.MIMEType, m.Header); err != nil {
-				im.log.WithError(err).
-					WithField("msgID", m.ID).
-					Warn("Cannot update header while building")
-			}
-			// Drafts can change and we don't want to cache them.
-			if !isMessageInDraftFolder(m) {
-				cache.SaveMail(id, body, structure)
-			}
-			bodyReader = bytes.NewReader(body)
-		}
-		if _, ok := err.(*doNotCacheError); ok {
-			im.log.WithField("msgID", m.ID).Errorf("do not cache message: %v", err)
-			err = nil
-			bodyReader = bytes.NewReader(body)
-		}
-	}
-	cache.BuildUnlock(id)
-	return structure, bodyReader, err
-}
-
-func isMessageInDraftFolder(m *pmapi.Message) bool {
-	for _, labelID := range m.LabelIDs {
-		if labelID == pmapi.DraftLabel {
-			return true
-		}
-	}
-	return false
-}
-
-// This will download message (or read from cache) and pick up the section,
-// extract data (header,body, both) and trim the output if needed.
-func (im *imapMailbox) getMessageBodySection(storeMessage storeMessageProvider, section *imap.BodySectionName) (literal imap.Literal, err error) { // nolint[funlen]
-	var (
-		structure  *message.BodyStructure
-		bodyReader *bytes.Reader
-		header     textproto.MIMEHeader
-		response   []byte
-	)
-
-	im.log.WithField("msgID", storeMessage.ID()).Trace("Getting message body")
-
-	m := storeMessage.Message()
-
-	if len(section.Path) == 0 && section.Specifier == imap.HeaderSpecifier {
-		// We can extract message header without decrypting.
-		header = message.GetHeader(m)
-		// We need to ensure we use the correct content-type,
-		// otherwise AppleMail expects `text/plain` in HTML mails.
-		if header.Get("Content-Type") == "" {
-			if err = im.fetchMessage(m); err != nil {
-				return
-			}
-			if _, err = im.setMessageContentType(m); err != nil {
-				return
-			}
-			if err = storeMessage.SetContentTypeAndHeader(m.MIMEType, m.Header); err != nil {
-				return
-			}
-			header = message.GetHeader(m)
-		}
-	} else {
-		// The rest of cases need download and decrypt.
-		structure, bodyReader, err = im.getBodyAndStructure(storeMessage)
-		if err != nil {
-			return
-		}
-
-		switch {
-		case section.Specifier == imap.EntireSpecifier && len(section.Path) == 0:
-			//  An empty section specification refers to the entire message, including the header.
-			response, err = structure.GetSection(bodyReader, section.Path)
-		case section.Specifier == imap.TextSpecifier || (section.Specifier == imap.EntireSpecifier && len(section.Path) != 0):
-			// The TEXT specifier refers to the content of the message (or section), omitting the [RFC-2822] header.
-			// Non-empty section with no specifier (imap.EntireSpecifier) refers to section content without header.
-			response, err = structure.GetSectionContent(bodyReader, section.Path)
-		case section.Specifier == imap.MIMESpecifier:
-			// The MIME part specifier refers to the [MIME-IMB] header for this part.
-			fallthrough
-		case section.Specifier == imap.HeaderSpecifier:
-			header, err = structure.GetSectionHeader(section.Path)
-		default:
-			err = errors.New("Unknown specifier " + string(section.Specifier))
-		}
-	}
-
-	if err != nil {
-		return
-	}
-
-	// Filter header. Options are: all fields, only selected fields, all fields except selected.
-	if header != nil {
-		// remove fields
-		if len(section.Fields) != 0 && section.NotFields {
-			for _, field := range section.Fields {
-				header.Del(field)
-			}
-		}
-
-		fields := make([]string, 0, len(header))
-		if len(section.Fields) == 0 || section.NotFields { // add all and sort
-			for f := range header {
-				fields = append(fields, f)
-			}
-			sort.Strings(fields)
-		} else { // add only requested (in requested order)
-			for _, f := range section.Fields {
-				fields = append(fields, textproto.CanonicalMIMEHeaderKey(f))
-			}
-		}
-
-		headerBuf := &bytes.Buffer{}
-		for _, canonical := range fields {
-			if values, ok := header[canonical]; !ok {
-				continue
-			} else {
-				for _, val := range values {
-					fmt.Fprintf(headerBuf, "%s: %s\r\n", canonical, val)
-				}
-			}
-		}
-		response = headerBuf.Bytes()
-	}
-
-	// Trim any output if requested.
-	literal = bytes.NewBuffer(section.ExtractPartial(response))
-	return literal, nil
-}
-
-func (im *imapMailbox) fetchMessage(m *pmapi.Message) (err error) {
-	im.log.Trace("Fetching message")
-
-	complete, err := im.storeMailbox.FetchMessage(m.ID)
-	if err != nil {
-		im.log.WithError(err).Error("Could not get message from store")
-		return
-	}
-
-	*m = *complete.Message()
-
-	return
-}
-
-func (im *imapMailbox) writeMessageBody(w io.Writer, m *pmapi.Message) (err error) {
-	im.log.Trace("Writing message body")
-
-	if m.Body == "" {
-		im.log.Trace("While writing message body, noticed message body is null, need to fetch")
-		if err = im.fetchMessage(m); err != nil {
-			return
-		}
-	}
-
-	kr, err := im.user.client().KeyRingForAddressID(m.AddressID)
-	if err != nil {
-		return errors.Wrap(err, "failed to get keyring for address ID")
-	}
-
-	err = message.WriteBody(w, kr, m)
-	if err != nil {
-		if customMessageErr := message.CustomMessage(m, err, true); customMessageErr != nil {
-			im.log.WithError(customMessageErr).Warn("Failed to make custom message")
-		}
-		_, _ = io.WriteString(w, m.Body)
-		err = nil
-	}
-
-	return
-}
-
-func (im *imapMailbox) writeAttachmentBody(w io.Writer, m *pmapi.Message, att *pmapi.Attachment) (err error) {
-	// Retrieve encrypted attachment.
-	r, err := im.user.client().GetAttachment(att.ID)
-	if err != nil {
-		return
-	}
-	defer r.Close() //nolint[errcheck]
-
-	kr, err := im.user.client().KeyRingForAddressID(m.AddressID)
-	if err != nil {
-		return errors.Wrap(err, "failed to get keyring for address ID")
-	}
-
-	if err = message.WriteAttachmentBody(w, kr, m, att, r); err != nil {
-		// Returning an error here makes certain mail clients behave badly,
-		// trying to retrieve the message again and again.
-		im.log.Warn("Cannot write attachment body: ", err)
-		err = nil
-	}
-	return
-}
-
-func (im *imapMailbox) writeRelatedPart(p io.Writer, m *pmapi.Message, inlines []*pmapi.Attachment) (err error) {
-	related := multipart.NewWriter(p)
-
-	_ = related.SetBoundary(message.GetRelatedBoundary(m))
-
-	buf := &bytes.Buffer{}
-	if err = im.writeMessageBody(buf, m); err != nil {
-		return
-	}
-
-	// Write the body part.
-	h := message.GetBodyHeader(m)
-
-	if p, err = related.CreatePart(h); err != nil {
-		return
-	}
-
-	_, _ = buf.WriteTo(p)
-
-	for _, inline := range inlines {
-		buf = &bytes.Buffer{}
-		if err = im.writeAttachmentBody(buf, m, inline); err != nil {
-			return
-		}
-
-		h := message.GetAttachmentHeader(inline)
-		if p, err = related.CreatePart(h); err != nil {
-			return
-		}
-		_, _ = buf.WriteTo(p)
-	}
-
-	_ = related.Close()
-	return nil
-}
-
-const (
-	noMultipart      = iota // only body
-	simpleMultipart         // body + attachment or inline
-	complexMultipart        // mixed, rfc822, alternatives, ...
-)
-
-func (im *imapMailbox) setMessageContentType(m *pmapi.Message) (multipartType int, err error) {
-	if m.MIMEType == "" {
-		err = fmt.Errorf("trying to set Content-Type without MIME TYPE")
-		return
-	}
-	// message.MIMEType can have just three values from our server:
-	// * `text/html` (refers to body type, but might contain attachments and inlines)
-	// * `text/plain` (refers to body type, but might contain attachments and inlines)
-	// * `multipart/mixed` (refers to external message with multipart structure)
-	// The proper header content fields must be set and saved to DB based MIMEType and content.
-	multipartType = noMultipart
-	if m.MIMEType == pmapi.ContentTypeMultipartMixed {
-		multipartType = complexMultipart
-	} else if m.NumAttachments != 0 {
-		multipartType = simpleMultipart
-	}
-
-	h := textproto.MIMEHeader(m.Header)
-	if multipartType == noMultipart {
-		message.SetBodyContentFields(&h, m)
-	} else {
-		h.Set("Content-Type",
-			fmt.Sprintf("%s; boundary=%s", "multipart/mixed", message.GetBoundary(m)),
-		)
-	}
-	m.Header = mail.Header(h)
-
-	return
-}
-
-// buildMessage from PM to IMAP.
-func (im *imapMailbox) buildMessage(m *pmapi.Message) (structure *message.BodyStructure, msgBody []byte, err error) {
-	im.log.Trace("Building message")
-
-	var errNoCache doNotCacheError
-
-	// If fetch or decryption fails we need to change the MIMEType (in customMessage).
-	err = im.fetchMessage(m)
-	if err != nil {
-		return
-	}
-
-	kr, err := im.user.client().KeyRingForAddressID(m.AddressID)
-	if err != nil {
-		err = errors.Wrap(err, "failed to get keyring for address ID")
-		return
-	}
-
-	errDecrypt := m.Decrypt(kr)
-
-	if errDecrypt != nil && errDecrypt != openpgperrors.ErrSignatureExpired {
-		errNoCache.add(errDecrypt)
-		if customMessageErr := message.CustomMessage(m, errDecrypt, true); customMessageErr != nil {
-			im.log.WithError(customMessageErr).Warn("Failed to make custom message")
-		}
-	}
-
-	// Inner function can fail even when message is decrypted.
-	// #1048 For example we have problem with double-encrypted messages
-	// which seems as still encrypted and we try them to decrypt again
-	// and that fails. For any building error is better to return custom
-	// message than error because it will not be fixed and users would
-	// get error message all the time and could not see some messages.
-	structure, msgBody, err = im.buildMessageInner(m, kr)
-	if err == pmapi.ErrAPINotReachable || err == pmapi.ErrInvalidToken || err == pmapi.ErrUpgradeApplication {
-		return nil, nil, err
-	} else if err != nil {
-		errNoCache.add(err)
-		if customMessageErr := message.CustomMessage(m, err, true); customMessageErr != nil {
-			im.log.WithError(customMessageErr).Warn("Failed to make custom message")
-		}
-		structure, msgBody, err = im.buildMessageInner(m, kr)
-		if err != nil {
-			return nil, nil, err
-		}
-	}
-
-	err = errNoCache.errorOrNil()
-
-	return structure, msgBody, err
-}
-
-func (im *imapMailbox) buildMessageInner(m *pmapi.Message, kr *crypto.KeyRing) (structure *message.BodyStructure, msgBody []byte, err error) { // nolint[funlen]
-	multipartType, err := im.setMessageContentType(m)
-	if err != nil {
-		return
-	}
-
-	tmpBuf := &bytes.Buffer{}
-	mainHeader := buildHeader(m)
-	if err = writeHeader(tmpBuf, mainHeader); err != nil {
-		return
-	}
-	_, _ = io.WriteString(tmpBuf, "\r\n")
-
-	switch multipartType {
-	case noMultipart:
-		err = message.WriteBody(tmpBuf, kr, m)
-		if err != nil {
-			return
-		}
-	case complexMultipart:
-		_, _ = io.WriteString(tmpBuf, "\r\n--"+message.GetBoundary(m)+"\r\n")
-		err = message.WriteBody(tmpBuf, kr, m)
-		if err != nil {
-			return
-		}
-		_, _ = io.WriteString(tmpBuf, "\r\n--"+message.GetBoundary(m)+"--\r\n")
-	case simpleMultipart:
-		atts, inlines := message.SeparateInlineAttachments(m)
-		mw := multipart.NewWriter(tmpBuf)
-		_ = mw.SetBoundary(message.GetBoundary(m))
-
-		var partWriter io.Writer
-
-		if len(inlines) > 0 {
-			relatedHeader := message.GetRelatedHeader(m)
-			if partWriter, err = mw.CreatePart(relatedHeader); err != nil {
-				return
-			}
-			_ = im.writeRelatedPart(partWriter, m, inlines)
-		} else {
-			buf := &bytes.Buffer{}
-			if err = im.writeMessageBody(buf, m); err != nil {
-				return
-			}
-
-			// Write the body part.
-			bodyHeader := message.GetBodyHeader(m)
-			if partWriter, err = mw.CreatePart(bodyHeader); err != nil {
-				return
-			}
-
-			_, _ = buf.WriteTo(partWriter)
-		}
-
-		// Write the attachments parts.
-		input := make([]interface{}, len(atts))
-		for i, att := range atts {
-			input[i] = att
-		}
-
-		processCallback := func(value interface{}) (interface{}, error) {
-			att := value.(*pmapi.Attachment)
-
-			buf := &bytes.Buffer{}
-			if err = im.writeAttachmentBody(buf, m, att); err != nil {
-				return nil, err
-			}
-			return buf, nil
-		}
-
-		collectCallback := func(idx int, value interface{}) error {
-			buf := value.(*bytes.Buffer)
-			defer buf.Reset()
-			att := atts[idx]
-
-			attachmentHeader := message.GetAttachmentHeader(att)
-			if partWriter, err = mw.CreatePart(attachmentHeader); err != nil {
-				return err
-			}
-
-			_, _ = buf.WriteTo(partWriter)
-			return nil
-		}
-
-		err = parallel.RunParallel(fetchAttachmentsWorkers, input, processCallback, collectCallback)
-		if err != nil {
-			return
-		}
-
-		_ = mw.Close()
-	default:
-		fmt.Fprintf(tmpBuf, "\r\n\r\nUknown multipart type: %d\r\n\r\n", multipartType)
-	}
-
-	// We need to copy buffer before building body structure.
-	msgBody = tmpBuf.Bytes()
-	structure, err = message.NewBodyStructure(tmpBuf)
-	if err != nil {
-		// NOTE: We need to set structure if it fails and is empty.
-		if structure == nil {
-			structure = &message.BodyStructure{}
-		}
-	}
-	return structure, msgBody, err
-}
-
-func buildHeader(msg *pmapi.Message) textproto.MIMEHeader {
-	header := message.GetHeader(msg)
-
-	msgTime := time.Unix(msg.Time, 0)
-
-	// Apple Mail crashes fetching messages with date older than 1970.
-	// There is no point having message older than RFC itself, it's not possible.
-	d, err := msg.Header.Date()
-	if err != nil || d.Before(rfc822Birthday) || msgTime.Before(rfc822Birthday) {
-		if err != nil || d.IsZero() {
-			header.Set("X-Original-Date", msgTime.Format(time.RFC1123Z))
-		} else {
-			header.Set("X-Original-Date", d.Format(time.RFC1123Z))
-		}
-		header.Set("Date", rfc822Birthday.Format(time.RFC1123Z))
-	}
-
-	return header
-}

internal/imap/mailbox_messages.go

@@ -18,7 +18,6 @@
 package imap
 
 import (
-	"errors"
 	"fmt"
 	"net/mail"
 	"strings"
@@ -30,6 +29,7 @@ import (
 	"github.com/ProtonMail/proton-bridge/pkg/parallel"
 	"github.com/ProtonMail/proton-bridge/pkg/pmapi"
 	"github.com/emersion/go-imap"
+	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 )
 
@@ -141,7 +141,7 @@ func (im *imapMailbox) addOrRemoveFlags(operation imap.FlagsOp, messageIDs, flag
 	for _, f := range flags {
 		switch f {
 		case imap.SeenFlag:
-			switch operation {
+			switch operation { //nolint[exhaustive] imap.SetFlags is processed by im.setFlags
 			case imap.AddFlags:
 				if err := im.storeMailbox.MarkMessagesRead(messageIDs); err != nil {
 					return err
@@ -152,7 +152,7 @@ func (im *imapMailbox) addOrRemoveFlags(operation imap.FlagsOp, messageIDs, flag
 				}
 			}
 		case imap.FlaggedFlag:
-			switch operation {
+			switch operation { //nolint[exhaustive] imap.SetFlag is processed by im.setFlags
 			case imap.AddFlags:
 				if err := im.storeMailbox.MarkMessagesStarred(messageIDs); err != nil {
 					return err
@@ -163,7 +163,7 @@ func (im *imapMailbox) addOrRemoveFlags(operation imap.FlagsOp, messageIDs, flag
 				}
 			}
 		case imap.DeletedFlag:
-			switch operation {
+			switch operation { //nolint[exhaustive] imap.SetFlag is processed by im.setFlags
 			case imap.AddFlags:
 				if err := im.storeMailbox.MarkMessagesDeleted(messageIDs); err != nil {
 					return err
@@ -182,7 +182,7 @@ func (im *imapMailbox) addOrRemoveFlags(operation imap.FlagsOp, messageIDs, flag
 			}
 
 			// Handle custom junk flags for Apple Mail and Thunderbird.
-			switch operation {
+			switch operation { //nolint[exhaustive] imap.SetFlag is processed by im.setFlags
 			// No label removal is necessary because Spam and Inbox are both exclusive labels so the backend
 			// will automatically take care of label removal.
 			case imap.AddFlags:
@@ -358,23 +358,28 @@ func (im *imapMailbox) SearchMessages(isUID bool, criteria *imap.SearchCriteria)
 				continue
 			}
 		}
+
+		// In order to speed up search it is not needed to check if IsFullHeaderCached.
+		header := storeMessage.GetMIMEHeader()
+
 		if !criteria.SentBefore.IsZero() || !criteria.SentSince.IsZero() {
-			if t, err := m.Header.Date(); err == nil && !t.IsZero() {
+			t, err := mail.Header(header).Date()
-				if !criteria.SentBefore.IsZero() {
+			if err != nil || t.IsZero() {
-					if truncated := criteria.SentBefore.Truncate(24 * time.Hour); t.Unix() > truncated.Unix() {
+				t = time.Unix(m.Time, 0)
-						continue
+			}
-					}
+			if !criteria.SentBefore.IsZero() {
+				if truncated := criteria.SentBefore.Truncate(24 * time.Hour); t.Unix() > truncated.Unix() {
+					continue
 				}
-				if !criteria.SentSince.IsZero() {
+			}
-					if truncated := criteria.SentSince.Truncate(24 * time.Hour); t.Unix() < truncated.Unix() {
+			if !criteria.SentSince.IsZero() {
-						continue
+				if truncated := criteria.SentSince.Truncate(24 * time.Hour); t.Unix() < truncated.Unix() {
-					}
+					continue
 				}
 			}
 		}
 
 		// Filter by headers.
-		header := message.GetHeader(m)
 		headerMatch := true
 		for criteriaKey, criteriaValues := range criteria.Header {
 			for _, criteriaValue := range criteriaValues {
@@ -382,6 +387,8 @@ func (im *imapMailbox) SearchMessages(isUID bool, criteria *imap.SearchCriteria)
 					continue
 				}
 				switch criteriaKey {
+				case "Subject":
+					headerMatch = strings.Contains(strings.ToLower(m.Subject), strings.ToLower(criteriaValue))
 				case "From":
 					headerMatch = addressMatch([]*mail.Address{m.Sender}, criteriaValue)
 				case "To":
@@ -414,7 +421,7 @@ func (im *imapMailbox) SearchMessages(isUID bool, criteria *imap.SearchCriteria)
 		if isStringInList(m.LabelIDs, pmapi.StarredLabel) {
 			messageFlagsMap[imap.FlaggedFlag] = true
 		}
-		if m.Unread == 0 {
+		if !m.Unread {
 			messageFlagsMap[imap.SeenFlag] = true
 		}
 		if m.Has(pmapi.FlagReplied) || m.Has(pmapi.FlagRepliedAll) {
@@ -482,12 +489,13 @@ func (im *imapMailbox) SearchMessages(isUID bool, criteria *imap.SearchCriteria)
 //
 // Messages must be sent to msgResponse. When the function returns, msgResponse must be closed.
 func (im *imapMailbox) ListMessages(isUID bool, seqSet *imap.SeqSet, items []imap.FetchItem, msgResponse chan<- *imap.Message) error {
+	msgBuildCountHistogram := newMsgBuildCountHistogram()
 	return im.logCommand(func() error {
-		return im.listMessages(isUID, seqSet, items, msgResponse)
+		return im.listMessages(isUID, seqSet, items, msgResponse, msgBuildCountHistogram)
-	}, "FETCH", isUID, seqSet, items)
+	}, "FETCH", isUID, seqSet, items, msgBuildCountHistogram)
 }
 
-func (im *imapMailbox) listMessages(isUID bool, seqSet *imap.SeqSet, items []imap.FetchItem, msgResponse chan<- *imap.Message) (err error) { //nolint[funlen]
+func (im *imapMailbox) listMessages(isUID bool, seqSet *imap.SeqSet, items []imap.FetchItem, msgResponse chan<- *imap.Message, msgBuildCountHistogram *msgBuildCountHistogram) (err error) { //nolint[funlen]
 	defer func() {
 		close(msgResponse)
 		if err != nil {
@@ -517,25 +525,13 @@ func (im *imapMailbox) listMessages(isUID bool, seqSet *imap.SeqSet, items []ima
 		return err
 	}
 
-	// From RFC: UID range of 559:* always includes the UID of the last message
-	// in the mailbox, even if 559 is higher than any assigned UID value.
-	// See: https://tools.ietf.org/html/rfc3501#page-61
-	if isUID && seqSet.Dynamic() && len(apiIDs) == 0 {
-		l.Debug("Requesting empty UID dynamic fetch, adding latest message")
-		apiID, err := im.storeMailbox.GetLatestAPIID()
-		if err != nil {
-			return nil
-		}
-		apiIDs = []string{apiID}
-	}
-
 	input := make([]interface{}, len(apiIDs))
 	for i, apiID := range apiIDs {
 		input[i] = apiID
 	}
 
 	processCallback := func(value interface{}) (interface{}, error) {
-		apiID := value.(string)
+		apiID := value.(string) //nolint[forcetypeassert] we want to panic here
 
 		storeMessage, err := im.storeMailbox.GetMessage(apiID)
 		if err != nil {
@@ -544,14 +540,14 @@ func (im *imapMailbox) listMessages(isUID bool, seqSet *imap.SeqSet, items []ima
 			return nil, err
 		}
 
-		msg, err := im.getMessage(storeMessage, items)
+		msg, err := im.getMessage(storeMessage, items, msgBuildCountHistogram)
 		if err != nil {
 			err = fmt.Errorf("list message build: %v", err)
 			l.WithField("metaID", storeMessage.ID()).Error(err)
 			return nil, err
 		}
 
-		if storeMessage.Message().Unread == 1 {
+		if storeMessage.Message().Unread {
 			for section := range msg.Body {
 				// Peek means get messages without marking them as read.
 				// If client does not only ask for peek, we have to mark them as read.
@@ -569,12 +565,12 @@ func (im *imapMailbox) listMessages(isUID bool, seqSet *imap.SeqSet, items []ima
 	}
 
 	collectCallback := func(idx int, value interface{}) error {
-		msg := value.(*imap.Message)
+		msg := value.(*imap.Message) //nolint[forcetypeassert] we want to panic here
 		msgResponse <- msg
 		return nil
 	}
 
-	err = parallel.RunParallel(fetchMessagesWorkers, input, processCallback, collectCallback)
+	err = parallel.RunParallel(fetchWorkers, input, processCallback, collectCallback)
 	if err != nil {
 		return err
 	}

internal/imap/msg_build_counts.go

@@ -0,0 +1,65 @@
+// Copyright (c) 2021 Proton Technologies AG
+//
+// This file is part of ProtonMail Bridge.
+//
+// ProtonMail Bridge is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// ProtonMail Bridge is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with ProtonMail Bridge.  If not, see <https://www.gnu.org/licenses/>.
+
+package imap
+
+import (
+	"fmt"
+	"sync"
+)
+
+// msgBuildCountHistogram is used to analyse and log the number of repetitive
+// downloads of requested messages per one fetch. The number of builds per each
+// messageID is stored in persistent database. The msgBuildCountHistogram will
+// take this number for each message in ongoing fetch and create histogram of
+// repeats.
+//
+// Example: During `fetch 1:300` there were
+// - 100 messages were downloaded first time
+// - 100 messages were downloaded second time
+// - 99 messages were downloaded 10th times
+// - 1 messages were downloaded 100th times.
+type msgBuildCountHistogram struct {
+	// Key represents how many times message was build.
+	// Value stores how many messages are build X times based on the key.
+	counts map[uint32]uint32
+	lock   sync.Locker
+}
+
+func newMsgBuildCountHistogram() *msgBuildCountHistogram {
+	return &msgBuildCountHistogram{
+		counts: map[uint32]uint32{},
+		lock:   &sync.Mutex{},
+	}
+}
+
+func (c *msgBuildCountHistogram) String() string {
+	res := ""
+	for nRebuild, counts := range c.counts {
+		if res != "" {
+			res += ", "
+		}
+		res += fmt.Sprintf("[%d]:%d", nRebuild, counts)
+	}
+	return res
+}
+
+func (c *msgBuildCountHistogram) add(nRebuild uint32) {
+	c.lock.Lock()
+	defer c.lock.Unlock()
+	c.counts[nRebuild]++
+}

internal/imap/server.go

@@ -32,8 +32,8 @@ import (
 	"github.com/ProtonMail/proton-bridge/internal/events"
 	"github.com/ProtonMail/proton-bridge/internal/imap/id"
 	"github.com/ProtonMail/proton-bridge/internal/imap/uidplus"
+	"github.com/ProtonMail/proton-bridge/internal/serverutil"
 	"github.com/ProtonMail/proton-bridge/pkg/listener"
-	"github.com/ProtonMail/proton-bridge/pkg/ports"
 	"github.com/emersion/go-imap"
 	imapappendlimit "github.com/emersion/go-imap-appendlimit"
 	imapidle "github.com/emersion/go-imap-idle"
@@ -116,60 +116,63 @@ func NewIMAPServer(panicHandler panicHandler, debugClient, debugServer bool, por
 	return server
 }
 
-// Starts the server.
+func (s *imapServer) HandlePanic()    { s.panicHandler.HandlePanic() }
-func (s *imapServer) ListenAndServe() {
+func (s *imapServer) IsRunning() bool { return s.isRunning.Load().(bool) }
-	go s.monitorDisconnectedUsers()
+func (s *imapServer) Port() int       { return s.port }
-	go s.monitorInternetConnection()
 
-	// When starting the Bridge, we don't want to retry to notify user
+// ListenAndServe starts the server and keeps it on based on internet
-	// quickly about the issue. Very probably retry will not help anyway.
+// availability.
-	s.listenAndServe(0)
+func (s *imapServer) ListenAndServe() {
+	serverutil.ListenAndServe(s, s.eventListener)
 }
 
-func (s *imapServer) listenAndServe(retries int) {
+// ListenRetryAndServe will start listener. If port is occupied it will try
-	if s.isRunning.Load().(bool) {
+// again after coolDown time. Once listener is OK it will serve.
+func (s *imapServer) ListenRetryAndServe(retries int, retryAfter time.Duration) {
+	if s.IsRunning() {
 		return
 	}
 	s.isRunning.Store(true)
 
-	log.Info("IMAP server listening at ", s.server.Addr)
+	l := log.WithField("address", s.server.Addr)
-	l, err := net.Listen("tcp", s.server.Addr)
+	l.Info("IMAP server is starting")
+	listener, err := net.Listen("tcp", s.server.Addr)
 	if err != nil {
 		s.isRunning.Store(false)
 		if retries > 0 {
-			log.WithError(err).WithField("retries", retries).Warn("IMAP listener failed")
+			l.WithError(err).WithField("retries", retries).Warn("IMAP listener failed")
-			time.Sleep(15 * time.Second)
+			time.Sleep(retryAfter)
-			s.listenAndServe(retries - 1)
+			s.ListenRetryAndServe(retries-1, retryAfter)
 			return
 		}
 
-		log.WithError(err).Error("IMAP listener failed")
+		l.WithError(err).Error("IMAP listener failed")
 		s.eventListener.Emit(events.ErrorEvent, "IMAP failed: "+err.Error())
 		return
 	}
 
 	err = s.server.Serve(&connListener{
-		Listener:  l,
+		Listener:  listener,
 		server:    s,
 		userAgent: s.userAgent,
 	})
 	// Serve returns error every time, even after closing the server.
 	// User shouldn't be notified about error if server shouldn't be running,
 	// but it should in case it was not closed by `s.Close()`.
-	if err != nil && s.isRunning.Load().(bool) {
+	if err != nil && s.IsRunning() {
 		s.isRunning.Store(false)
-		log.WithError(err).Error("IMAP server failed")
+		l.WithError(err).Error("IMAP server failed")
 		s.eventListener.Emit(events.ErrorEvent, "IMAP failed: "+err.Error())
 		return
 	}
 	defer s.server.Close() //nolint[errcheck]
 
-	log.Info("IMAP server stopped")
+	l.Info("IMAP server stopped")
 }
 
 // Stops the server.
 func (s *imapServer) Close() {
-	if !s.isRunning.Load().(bool) {
+	if !s.IsRunning() {
 		return
 	}
 	s.isRunning.Store(false)
@@ -180,62 +183,16 @@ func (s *imapServer) Close() {
 	}
 }
 
-func (s *imapServer) monitorInternetConnection() {
+func (s *imapServer) DisconnectUser(address string) {
-	on := make(chan string)
+	log.Info("Disconnecting all open IMAP connections for ", address)
-	s.eventListener.Add(events.InternetOnEvent, on)
+	s.server.ForEachConn(func(conn imapserver.Conn) {
-	off := make(chan string)
+		connUser := conn.Context().User
-	s.eventListener.Add(events.InternetOffEvent, off)
+		if connUser != nil && strings.EqualFold(connUser.Username(), address) {
-
+			if err := conn.Close(); err != nil {
-	for {
+				log.WithError(err).Error("Failed to close the connection")
-		var expectedIsPortFree bool
-		select {
-		case <-on:
-			go func() {
-				defer s.panicHandler.HandlePanic()
-				// We had issues on Mac that from time to time something
-				// blocked our port for a bit after we closed IMAP server
-				// due to connection issues.
-				// Restart always helped, so we do retry to not bother user.
-				s.listenAndServe(10)
-			}()
-			expectedIsPortFree = false
-		case <-off:
-			s.Close()
-			expectedIsPortFree = true
-		}
-
-		start := time.Now()
-		for {
-			if ports.IsPortFree(s.port) == expectedIsPortFree {
-				break
-			}
-			// Safety stop if something went wrong.
-			if time.Since(start) > 15*time.Second {
-				log.WithField("expectedIsPortFree", expectedIsPortFree).Warn("Server start/stop check timeouted")
-				break
-			}
-			time.Sleep(100 * time.Millisecond)
-		}
-	}
-}
-
-func (s *imapServer) monitorDisconnectedUsers() {
-	ch := make(chan string)
-	s.eventListener.Add(events.CloseConnectionEvent, ch)
-
-	for address := range ch {
-		address := address
-		log.Info("Disconnecting all open IMAP connections for ", address)
-		disconnectUser := func(conn imapserver.Conn) {
-			connUser := conn.Context().User
-			if connUser != nil && strings.EqualFold(connUser.Username(), address) {
-				if err := conn.Close(); err != nil {
-					log.WithError(err).Error("Failed to close the connection")
-				}
 			}
 		}
-		s.server.ForEachConn(disconnectUser)
+	})
-	}
 }
 
 // connListener sets debug loggers on server containing fields with local

internal/imap/server_test.go

@@ -20,48 +20,33 @@ package imap
 import (
 	"fmt"
 	"testing"
-	"time"
 
 	"github.com/ProtonMail/proton-bridge/internal/bridge"
 	"github.com/ProtonMail/proton-bridge/internal/config/useragent"
-	"github.com/ProtonMail/proton-bridge/internal/events"
+	"github.com/ProtonMail/proton-bridge/internal/serverutil/mocks"
-	"github.com/ProtonMail/proton-bridge/pkg/listener"
-	"github.com/ProtonMail/proton-bridge/pkg/ports"
 	imapserver "github.com/emersion/go-imap/server"
 
 	"github.com/stretchr/testify/require"
 )
 
-type testPanicHandler struct{}
-
-func (ph *testPanicHandler) HandlePanic() {}
-
 func TestIMAPServerTurnOffAndOnAgain(t *testing.T) {
-	panicHandler := &testPanicHandler{}
+	r := require.New(t)
+	ts := mocks.NewTestServer(12345)
 
-	eventListener := listener.New()
-
-	port := ports.FindFreePortFrom(12345)
 	server := imapserver.New(nil)
-	server.Addr = fmt.Sprintf("%v:%v", bridge.Host, port)
+	server.Addr = fmt.Sprintf("%v:%v", bridge.Host, ts.WantPort)
 
 	s := &imapServer{
-		panicHandler:  panicHandler,
+		panicHandler:  ts.PanicHandler,
 		server:        server,
-		eventListener: eventListener,
+		port:          ts.WantPort,
+		eventListener: ts.EventListener,
 		userAgent:     useragent.New(),
 	}
 	s.isRunning.Store(false)
 
+	r.True(ts.IsPortFree())
+
 	go s.ListenAndServe()
-	time.Sleep(5 * time.Second)
+	ts.RunServerTests(r)
-	require.False(t, ports.IsPortFree(port))
-
-	eventListener.Emit(events.InternetOffEvent, "")
-	time.Sleep(10 * time.Second)
-	require.True(t, ports.IsPortFree(port))
-
-	eventListener.Emit(events.InternetOnEvent, "")
-	time.Sleep(10 * time.Second)
-	require.False(t, ports.IsPortFree(port))
 }

internal/imap/store.go

@@ -20,6 +20,7 @@ package imap
 import (
 	"io"
 	"net/mail"
+	"net/textproto"
 
 	"github.com/ProtonMail/gopenpgp/v2/crypto"
 	"github.com/ProtonMail/proton-bridge/internal/imap/uidplus"
@@ -100,9 +101,13 @@ type storeMessageProvider interface {
 	IsMarkedDeleted() bool
 
 	SetSize(int64) error
-	SetContentTypeAndHeader(string, mail.Header) error
+	SetHeader([]byte) error
+	GetHeader() []byte
+	GetMIMEHeader() textproto.MIMEHeader
+	IsFullHeaderCached() bool
 	SetBodyStructure(*pkgMsg.BodyStructure) error
 	GetBodyStructure() (*pkgMsg.BodyStructure, error)
+	IncreaseBuildCount() (uint32, error)
 }
 
 type storeUserWrap struct {
@@ -122,7 +127,7 @@ func (s *storeUserWrap) GetAddress(addressID string) (storeAddressProvider, erro
 	if err != nil {
 		return nil, err
 	}
-	return newStoreAddressWrap(address), nil
+	return newStoreAddressWrap(address), nil //nolint[typecheck] missing methods are inherited
 }
 
 type storeAddressWrap struct {
@@ -136,7 +141,7 @@ func newStoreAddressWrap(address *store.Address) *storeAddressWrap {
 func (s *storeAddressWrap) ListMailboxes() []storeMailboxProvider {
 	mailboxes := []storeMailboxProvider{}
 	for _, mailbox := range s.Address.ListMailboxes() {
-		mailboxes = append(mailboxes, newStoreMailboxWrap(mailbox))
+		mailboxes = append(mailboxes, newStoreMailboxWrap(mailbox)) //nolint[typecheck] missing methods are inherited
 	}
 	return mailboxes
 }
@@ -146,7 +151,7 @@ func (s *storeAddressWrap) GetMailbox(name string) (storeMailboxProvider, error)
 	if err != nil {
 		return nil, err
 	}
-	return newStoreMailboxWrap(mailbox), nil
+	return newStoreMailboxWrap(mailbox), nil //nolint[typecheck] missing methods are inherited
 }
 
 type storeMailboxWrap struct {

internal/imap/uidplus/extension.go

@@ -33,7 +33,7 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
-// Capability extension identifier
+// Capability extension identifier.
 const Capability = "UIDPLUS"
 
 const (
@@ -228,7 +228,9 @@ func getStatusResponseCopy(uidValidity uint32, sourceSeq, targetSeq *OrderedSeq)
 
 // CopyResponse prepares OK response with extended UID information about copied message.
 func CopyResponse(uidValidity uint32, sourceSeq, targetSeq *OrderedSeq) error {
-	return server.ErrStatusResp(getStatusResponseCopy(uidValidity, sourceSeq, targetSeq))
+	return &imap.ErrStatusResp{
+		Resp: getStatusResponseCopy(uidValidity, sourceSeq, targetSeq),
+	}
 }
 
 func getStatusResponseAppend(uidValidity uint32, targetSeq *OrderedSeq) *imap.StatusResp {
@@ -250,5 +252,7 @@ func getStatusResponseAppend(uidValidity uint32, targetSeq *OrderedSeq) *imap.St
 
 // AppendResponse prepares OK response with extended UID information about appended message.
 func AppendResponse(uidValidity uint32, targetSeq *OrderedSeq) error {
-	return server.ErrStatusResp(getStatusResponseAppend(uidValidity, targetSeq))
+	return &imap.ErrStatusResp{
+		Resp: getStatusResponseAppend(uidValidity, targetSeq),
+	}
 }

internal/imap/user.go

@@ -93,7 +93,7 @@ func newIMAPUser(
 
 // This method should eventually no longer be necessary. Everything should go via store.
 func (iu *imapUser) client() pmapi.Client {
-	return iu.user.GetTemporaryPMAPIClient()
+	return iu.user.GetClient()
 }
 
 func (iu *imapUser) isSubscribed(labelID string) bool {
@@ -135,7 +135,7 @@ func (iu *imapUser) ListMailboxes(showOnlySubcribed bool) ([]goIMAPBackend.Mailb
 		if showOnlySubcribed && !iu.isSubscribed(storeMailbox.LabelID()) {
 			continue
 		}
-		mailbox := newIMAPMailbox(iu.panicHandler, iu, storeMailbox)
+		mailbox := newIMAPMailbox(iu.panicHandler, iu, storeMailbox, iu.backend.builder)
 		mailboxes = append(mailboxes, mailbox)
 	}
 
@@ -167,7 +167,7 @@ func (iu *imapUser) GetMailbox(name string) (mb goIMAPBackend.Mailbox, err error
 		return
 	}
 
-	return newIMAPMailbox(iu.panicHandler, iu, storeMailbox), nil
+	return newIMAPMailbox(iu.panicHandler, iu, storeMailbox, iu.backend.builder), nil
 }
 
 // CreateMailbox creates a new mailbox.

internal/importexport/importexport.go

@@ -20,7 +20,9 @@ package importexport
 
 import (
 	"bytes"
+	"context"
 
+	"github.com/ProtonMail/proton-bridge/internal/events"
 	"github.com/ProtonMail/proton-bridge/internal/transfer"
 	"github.com/ProtonMail/proton-bridge/internal/users"
 	"github.com/ProtonMail/proton-bridge/pkg/pmapi"
@@ -39,7 +41,8 @@ type ImportExport struct {
 	locations     Locator
 	cache         Cacher
 	panicHandler  users.PanicHandler
-	clientManager users.ClientManager
+	eventListener listener.Listener
+	clientManager pmapi.Manager
 }
 
 func New(
@@ -47,7 +50,7 @@ func New(
 	cache Cacher,
 	panicHandler users.PanicHandler,
 	eventListener listener.Listener,
-	clientManager users.ClientManager,
+	clientManager pmapi.Manager,
 	credStorer users.CredentialsStorer,
 ) *ImportExport {
 	u := users.New(locations, panicHandler, eventListener, clientManager, credStorer, &storeFactory{}, false)
@@ -58,69 +61,44 @@ func New(
 		locations:     locations,
 		cache:         cache,
 		panicHandler:  panicHandler,
+		eventListener: eventListener,
 		clientManager: clientManager,
 	}
 }
 
 // ReportBug reports a new bug from the user.
 func (ie *ImportExport) ReportBug(osType, osVersion, description, accountName, address, emailClient string) error {
-	c := ie.clientManager.GetAnonymousClient()
+	return ie.clientManager.ReportBug(context.Background(), pmapi.ReportBugReq{
-	defer c.Logout()
-
-	title := "[Import-Export] Bug"
-	report := pmapi.ReportReq{
 		OS:          osType,
 		OSVersion:   osVersion,
 		Browser:     emailClient,
-		Title:       title,
+		Title:       "[Import-Export] Bug",
 		Description: description,
 		Username:    accountName,
 		Email:       address,
-	}
+	})
-
-	if err := c.Report(report); err != nil {
-		log.Error("Reporting bug failed: ", err)
-		return err
-	}
-
-	log.Info("Bug successfully reported")
-
-	return nil
 }
 
-// ReportFile submits import report file
+// ReportFile submits import report file.
 func (ie *ImportExport) ReportFile(osType, osVersion, accountName, address string, logdata []byte) error {
-	c := ie.clientManager.GetAnonymousClient()
+	report := pmapi.ReportBugReq{
-	defer c.Logout()
-
-	title := "[Import-Export] report file"
-	description := "An Import-Export report from the user swam down the river."
-
-	report := pmapi.ReportReq{
 		OS:          osType,
 		OSVersion:   osVersion,
-		Description: description,
+		Description: "An Import-Export report from the user swam down the river.",
-		Title:       title,
+		Title:       "[Import-Export] report file",
 		Username:    accountName,
 		Email:       address,
 	}
 
 	report.AddAttachment("log", "report.log", bytes.NewReader(logdata))
 
-	if err := c.Report(report); err != nil {
+	return ie.clientManager.ReportBug(context.Background(), report)
-		log.Error("Sending report failed: ", err)
-		return err
-	}
-
-	log.Info("Report successfully sent")
-
-	return nil
 }
 
 // GetLocalImporter returns transferrer from local EML or MBOX structure to ProtonMail account.
-func (ie *ImportExport) GetLocalImporter(address, path string) (*transfer.Transfer, error) {
+func (ie *ImportExport) GetLocalImporter(username, address, path string) (*transfer.Transfer, error) {
 	source := transfer.NewLocalProvider(path)
-	target, err := ie.getPMAPIProvider(address)
+	target, err := ie.getPMAPIProvider(username, address)
 	if err != nil {
 		return nil, err
 	}
@@ -132,12 +110,12 @@ func (ie *ImportExport) GetLocalImporter(address, path string) (*transfer.Transf
 }
 
 // GetRemoteImporter returns transferrer from remote IMAP to ProtonMail account.
-func (ie *ImportExport) GetRemoteImporter(address, username, password, host, port string) (*transfer.Transfer, error) {
+func (ie *ImportExport) GetRemoteImporter(username, address, remoteUsername, remotePassword, host, port string) (*transfer.Transfer, error) {
-	source, err := transfer.NewIMAPProvider(username, password, host, port)
+	source, err := transfer.NewIMAPProvider(remoteUsername, remotePassword, host, port)
 	if err != nil {
 		return nil, err
 	}
-	target, err := ie.getPMAPIProvider(address)
+	target, err := ie.getPMAPIProvider(username, address)
 	if err != nil {
 		return nil, err
 	}
@@ -149,8 +127,8 @@ func (ie *ImportExport) GetRemoteImporter(address, username, password, host, por
 }
 
 // GetEMLExporter returns transferrer from ProtonMail account to local EML structure.
-func (ie *ImportExport) GetEMLExporter(address, path string) (*transfer.Transfer, error) {
+func (ie *ImportExport) GetEMLExporter(username, address, path string) (*transfer.Transfer, error) {
-	source, err := ie.getPMAPIProvider(address)
+	source, err := ie.getPMAPIProvider(username, address)
 	if err != nil {
 		return nil, err
 	}
@@ -163,8 +141,8 @@ func (ie *ImportExport) GetEMLExporter(address, path string) (*transfer.Transfer
 }
 
 // GetMBOXExporter returns transferrer from ProtonMail account to local MBOX structure.
-func (ie *ImportExport) GetMBOXExporter(address, path string) (*transfer.Transfer, error) {
+func (ie *ImportExport) GetMBOXExporter(username, address, path string) (*transfer.Transfer, error) {
-	source, err := ie.getPMAPIProvider(address)
+	source, err := ie.getPMAPIProvider(username, address)
 	if err != nil {
 		return nil, err
 	}
@@ -176,8 +154,8 @@ func (ie *ImportExport) GetMBOXExporter(address, path string) (*transfer.Transfe
 	return transfer.New(ie.panicHandler, newExportMetricsManager(ie), logsPath, ie.cache.GetTransferDir(), source, target)
 }
 
-func (ie *ImportExport) getPMAPIProvider(address string) (*transfer.PMAPIProvider, error) {
+func (ie *ImportExport) getPMAPIProvider(username, address string) (*transfer.PMAPIProvider, error) {
-	user, err := ie.Users.GetUser(address)
+	user, err := ie.Users.GetUser(username)
 	if err != nil {
 		return nil, err
 	}
@@ -187,5 +165,23 @@ func (ie *ImportExport) getPMAPIProvider(address string) (*transfer.PMAPIProvide
 		log.WithError(err).Info("Address does not exist, using all addresses")
 	}
 
-	return transfer.NewPMAPIProvider(ie.clientManager, user.ID(), addressID)
+	provider, err := transfer.NewPMAPIProvider(user.GetClient(), user.ID(), addressID)
+	if err != nil {
+		return nil, err
+	}
+
+	go func() {
+		internetOffCh := ie.eventListener.ProvideChannel(events.InternetOffEvent)
+		internetOnCh := ie.eventListener.ProvideChannel(events.InternetOnEvent)
+		for {
+			select {
+			case <-internetOffCh:
+				provider.SetConnectionDown()
+			case <-internetOnCh:
+				provider.SetConnectionUp()
+			}
+		}
+	}()
+
+	return provider, nil
 }

internal/locations/locations.go

@@ -32,9 +32,9 @@ import (
 // On linux:
 // - settings: ~/.config/protonmail/<app>
 // - logs: ~/.cache/protonmail/<app>/logs
-// - cache: ~/.cache/protonmail/<app>/cache
+// - cache: ~/.config/protonmail/<app>/cache
-// - updates: ~/.cache/protonmail/<app>/updates
+// - updates: ~/.config/protonmail/<app>/updates
-// - lockfile: ~/.cache/protonmail/<app>/<app>.lock
+// - lockfile: ~/.cache/protonmail/<app>/<app>.lock .
 type Locations struct {
 	userConfig, userCache string
 	configName            string
@@ -129,7 +129,7 @@ func (l *Locations) ProvideLogsPath() (string, error) {
 	return l.getLogsPath(), nil
 }
 
-// ProvideCachePath returns a location for user cache dirs (e.g. ~/.cache/<company>/<app>/cache).
+// ProvideCachePath returns a location for user cache dirs (e.g. ~/.config/<company>/<app>/cache).
 // It creates it if it doesn't already exist.
 func (l *Locations) ProvideCachePath() (string, error) {
 	if err := os.MkdirAll(l.getCachePath(), 0700); err != nil {
@@ -139,6 +139,11 @@ func (l *Locations) ProvideCachePath() (string, error) {
 	return l.getCachePath(), nil
 }
 
+// GetOldCachePath returns a former location for user cache dirs used for migration scripts only.
+func (l *Locations) GetOldCachePath() string {
+	return filepath.Join(l.userCache, "cache")
+}
+
 // ProvideUpdatesPath returns a location for update files (e.g. ~/.cache/<company>/<app>/updates).
 // It creates it if it doesn't already exist.
 func (l *Locations) ProvideUpdatesPath() (string, error) {
@@ -149,6 +154,16 @@ func (l *Locations) ProvideUpdatesPath() (string, error) {
 	return l.getUpdatesPath(), nil
 }
 
+// GetUpdatesPath returns a new location for update files used for migration scripts only.
+func (l *Locations) GetUpdatesPath() string {
+	return l.getUpdatesPath()
+}
+
+// GetOldUpdatesPath returns a former location for update files used for migration scripts only.
+func (l *Locations) GetOldUpdatesPath() string {
+	return filepath.Join(l.userCache, "updates")
+}
+
 func (l *Locations) getSettingsPath() string {
 	return l.userConfig
 }
@@ -158,11 +173,33 @@ func (l *Locations) getLogsPath() string {
 }
 
 func (l *Locations) getCachePath() string {
-	return filepath.Join(l.userCache, "cache")
+	// Bridge cache is not a typical cache which can be deleted with only
+	// downside that the app has to download everything again.
+	// Cache for bridge is database with IMAP UIDs and UIDVALIDITY, and also
+	// other IMAP setup. Deleting such data leads to either re-sync of client,
+	// or mix of headers and bodies. Both is caused because of need of re-sync
+	// between Bridge and API which will happen in different order than before.
+	// In the first case, UIDVALIDITY is also changed and causes the better
+	// outcome to "just" re-sync everything; in the later, UIDVALIDITY stays
+	// the same, causing the client to not re-sync but UIDs in the client does
+	// not match UIDs in Bridge.
+	// Because users might use tools to regularly clear caches, Bridge cache
+	// cannot be located in a standard cache folder.
+	return filepath.Join(l.userConfig, "cache")
 }
 
 func (l *Locations) getUpdatesPath() string {
-	return filepath.Join(l.userCache, "updates")
+	// In order to properly update Bridge 1.6.X and higher we need to
+	// change the launcher first. Since this is not part of automatic
+	// updates the migration must wait until manual update. Until that
+	// we need to keep old path.
+	if l.configName == "bridge" {
+		return l.GetOldUpdatesPath()
+	}
+
+	// Users might use tools to regularly clear caches, which would mean always
+	// removing updates, therefore Bridge updates have to be somewhere else.
+	return filepath.Join(l.userConfig, "updates")
 }
 
 // Clear removes everything except the lock and update files.

internal/locations/locations_test.go

@@ -45,7 +45,8 @@ func TestClearRemovesEverythingExceptLockAndUpdateFiles(t *testing.T) {
 	assert.NoError(t, l.Clear())
 
 	assert.FileExists(t, l.GetLockFile())
-	assert.NoDirExists(t, l.getSettingsPath())
+	assert.DirExists(t, l.getSettingsPath())
+	assert.NoFileExists(t, filepath.Join(l.getSettingsPath(), "prefs.json"))
 	assert.NoDirExists(t, l.getLogsPath())
 	assert.NoDirExists(t, l.getCachePath())
 	assert.DirExists(t, l.getUpdatesPath())
@@ -58,6 +59,7 @@ func TestClearUpdateFiles(t *testing.T) {
 
 	assert.FileExists(t, l.GetLockFile())
 	assert.DirExists(t, l.getSettingsPath())
+	assert.FileExists(t, filepath.Join(l.getSettingsPath(), "prefs.json"))
 	assert.DirExists(t, l.getLogsPath())
 	assert.DirExists(t, l.getCachePath())
 	assert.NoDirExists(t, l.getUpdatesPath())
@@ -75,6 +77,7 @@ func TestCleanLeavesStandardLocationsUntouched(t *testing.T) {
 
 	assert.FileExists(t, l.GetLockFile())
 	assert.DirExists(t, l.getSettingsPath())
+	assert.FileExists(t, filepath.Join(l.getSettingsPath(), "prefs.json"))
 	assert.DirExists(t, l.getLogsPath())
 	assert.FileExists(t, filepath.Join(l.getLogsPath(), "log1.txt"))
 	assert.FileExists(t, filepath.Join(l.getLogsPath(), "log2.txt"))
@@ -138,6 +141,9 @@ func newTestLocations(t *testing.T) *Locations {
 	require.NoError(t, err)
 	require.DirExists(t, settings)
 
+	createFilesInDir(t, settings, "prefs.json")
+	require.FileExists(t, filepath.Join(settings, "prefs.json"))
+
 	logs, err := l.ProvideLogsPath()
 	require.NoError(t, err)
 	require.DirExists(t, logs)

internal/logging/crash.go

@@ -34,7 +34,7 @@ func DumpStackTrace(logsPath string) crash.RecoveryAction {
 	return func(r interface{}) error {
 		file := filepath.Join(logsPath, getStackTraceName(constants.Version, constants.Revision))
 
-		f, err := os.OpenFile(file, os.O_WRONLY|os.O_APPEND|os.O_CREATE, 0600)
+		f, err := os.OpenFile(filepath.Clean(file), os.O_WRONLY|os.O_APPEND|os.O_CREATE, 0600)
 		if err != nil {
 			return err
 		}

internal/logging/logging.go

@@ -42,6 +42,7 @@ const (
 
 func Init(logsPath string) error {
 	logrus.SetFormatter(&logrus.TextFormatter{
+		ForceColors:     true,
 		FullTimestamp:   true,
 		TimestampFormat: time.StampMilli,
 	})
@@ -69,6 +70,10 @@ func Init(logsPath string) error {
 	return nil
 }
 
+// SetLevel will change the level of logging and in case of Debug or Trace
+// level it will also prevent from writing to file. Setting level to Info or
+// higher will not set writing to file again if it was previously cancelled by
+// Debug or Trace.
 func SetLevel(level string) {
 	if lvl, err := logrus.ParseLevel(level); err == nil {
 		logrus.SetLevel(lvl)

internal/serverutil/mocks/server.go

@@ -0,0 +1,150 @@
+// Copyright (c) 2021 Proton Technologies AG
+//
+// This file is part of ProtonMail Bridge.
+//
+// ProtonMail Bridge is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// ProtonMail Bridge is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with ProtonMail Bridge.  If not, see <https://www.gnu.org/licenses/>.
+
+package mocks
+
+import (
+	"fmt"
+	"net/http"
+	"sync/atomic"
+	"time"
+
+	"github.com/ProtonMail/proton-bridge/internal/events"
+	"github.com/ProtonMail/proton-bridge/pkg/listener"
+	"github.com/ProtonMail/proton-bridge/pkg/ports"
+	"github.com/sirupsen/logrus"
+	"github.com/stretchr/testify/require"
+)
+
+type DummyPanicHandler struct{}
+
+func (ph *DummyPanicHandler) HandlePanic() {}
+
+type TestServer struct {
+	PanicHandler  *DummyPanicHandler
+	WantPort      int
+	EventListener listener.Listener
+
+	isRunning atomic.Value
+	srv       *http.Server
+}
+
+func NewTestServer(port int) *TestServer {
+	s := &TestServer{
+		PanicHandler:  &DummyPanicHandler{},
+		EventListener: listener.New(),
+		WantPort:      ports.FindFreePortFrom(port),
+	}
+	s.isRunning.Store(false)
+	return s
+}
+
+func (s *TestServer) IsPortFree() bool {
+	return true
+}
+
+func (s *TestServer) IsPortOccupied() bool {
+	return true
+}
+
+func (s *TestServer) Emit(event string, try, iEvt int) int {
+	// Emit has separate go routine so it is needed to wait here to
+	// prevent event race condition.
+	time.Sleep(100 * time.Millisecond)
+	iEvt++
+	s.EventListener.Emit(event, fmt.Sprintf("%d:%d", try, iEvt))
+	return iEvt
+}
+
+func (s *TestServer) HandlePanic()          {}
+func (s *TestServer) DisconnectUser(string) {}
+func (s *TestServer) Port() int             { return s.WantPort }
+func (s *TestServer) IsRunning() bool       { return s.isRunning.Load().(bool) }
+
+func (s *TestServer) ListenRetryAndServe(retries int, retryAfter time.Duration) {
+	if s.isRunning.Load().(bool) {
+		return
+	}
+	s.isRunning.Store(true)
+
+	// There can be delay when starting server
+	time.Sleep(200 * time.Millisecond)
+
+	s.srv = &http.Server{
+		Addr: fmt.Sprintf("127.0.0.1:%d", s.WantPort),
+	}
+
+	err := s.srv.ListenAndServe()
+	if err != nil {
+		s.isRunning.Store(false)
+		if retries > 0 {
+			time.Sleep(retryAfter)
+			s.ListenRetryAndServe(retries-1, retryAfter)
+		}
+	}
+
+	if s.IsRunning() {
+		logrus.Error("Not serving but isRunning is true")
+		s.isRunning.Store(false)
+	}
+}
+
+func (s *TestServer) Close() {
+	if !s.isRunning.Load().(bool) {
+		return
+	}
+	s.isRunning.Store(false)
+
+	// There can be delay when stopping server
+	time.Sleep(200 * time.Millisecond)
+	if err := s.srv.Close(); err != nil {
+		logrus.WithError(err).Error("Closing dummy server")
+	}
+}
+
+func (s *TestServer) RunServerTests(r *require.Assertions) {
+	// NOTE About choosing tick durations:
+	// In order to avoid ticks to synchronise and cause occasional race
+	// condition we choose the tick duration around 100ms but not exactly
+	// to have large common multiple.
+	r.Eventually(s.IsPortOccupied, 5*time.Second, 97*time.Millisecond)
+
+	// There was an issue where second time we were not able to restore server.
+	for try := 0; try < 3; try++ {
+		i := s.Emit(events.InternetOffEvent, try, 0)
+		r.Eventually(s.IsPortFree, 10*time.Second, 99*time.Millisecond, "signal off try %d : %d", try, i)
+
+		i = s.Emit(events.InternetOnEvent, try, i)
+		i = s.Emit(events.InternetOffEvent, try, i)
+		i = s.Emit(events.InternetOffEvent, try, i)
+		i = s.Emit(events.InternetOffEvent, try, i)
+		i = s.Emit(events.InternetOffEvent, try, i)
+		i = s.Emit(events.InternetOnEvent, try, i)
+		i = s.Emit(events.InternetOnEvent, try, i)
+		i = s.Emit(events.InternetOffEvent, try, i)
+		// Wait a bit longer if needed to process all events
+		r.Eventually(s.IsPortFree, 20*time.Second, 101*time.Millisecond, "again signal off number %d : %d", try, i)
+
+		i = s.Emit(events.InternetOnEvent, try, i)
+		r.Eventually(s.IsPortOccupied, 10*time.Second, 103*time.Millisecond, "signal on number %d : %d", try, i)
+
+		i = s.Emit(events.InternetOffEvent, try, i)
+		i = s.Emit(events.InternetOnEvent, try, i)
+		i = s.Emit(events.InternetOnEvent, try, i)
+		r.Eventually(s.IsPortOccupied, 10*time.Second, 107*time.Millisecond, "again signal on number %d : %d", try, i)
+	}
+}

internal/serverutil/server.go

@@ -0,0 +1,132 @@
+// Copyright (c) 2021 Proton Technologies AG
+//
+// This file is part of ProtonMail Bridge.
+//
+// ProtonMail Bridge is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// ProtonMail Bridge is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with ProtonMail Bridge.  If not, see <https://www.gnu.org/licenses/>.
+
+package serverutil
+
+import (
+	"time"
+
+	"github.com/ProtonMail/proton-bridge/internal/events"
+	"github.com/ProtonMail/proton-bridge/pkg/listener"
+	"github.com/ProtonMail/proton-bridge/pkg/ports"
+	"github.com/sirupsen/logrus"
+)
+
+// Server which can handle disconnected users and lost internet connection.
+type Server interface {
+	HandlePanic()
+	DisconnectUser(string)
+	ListenRetryAndServe(int, time.Duration)
+	Close()
+	Port() int
+	IsRunning() bool
+}
+
+func monitorDisconnectedUsers(s Server, l listener.Listener) {
+	ch := make(chan string)
+	l.Add(events.CloseConnectionEvent, ch)
+	for address := range ch {
+		s.DisconnectUser(address)
+	}
+}
+
+func redirectInternetEventsToOneChannel(l listener.Listener) (isInternetOn chan bool) {
+	on := make(chan string)
+	l.Add(events.InternetOnEvent, on)
+	off := make(chan string)
+	l.Add(events.InternetOffEvent, off)
+
+	// Redirect two channels into one. When select was used the algorithm
+	// first read all on channels and then read all off channels.
+	isInternetOn = make(chan bool, 20)
+	go func() {
+		for {
+			logrus.WithField("try", <-on).Trace("Internet ON")
+			isInternetOn <- true
+		}
+	}()
+
+	go func() {
+		for {
+			logrus.WithField("try", <-off).Trace("Internet OFF")
+			isInternetOn <- false
+		}
+	}()
+	return
+}
+
+const (
+	recheckPortAfter    = 50 * time.Millisecond
+	stopPortChecksAfter = 15 * time.Second
+	retryListnerAfter   = 5 * time.Second
+)
+
+func monitorInternetConnection(s Server, l listener.Listener) {
+	isInternetOn := redirectInternetEventsToOneChannel(l)
+	for {
+		var expectedIsPortFree bool
+		if <-isInternetOn {
+			if s.IsRunning() {
+				continue
+			}
+			go func() {
+				defer s.HandlePanic()
+				// We had issues on Mac that from time to time something
+				// blocked our port for a bit after we closed IMAP server
+				// due to connection issues.
+				// Restart always helped, so we do retry to not bother user.
+				s.ListenRetryAndServe(10, retryListnerAfter)
+			}()
+			expectedIsPortFree = false
+		} else {
+			if !s.IsRunning() {
+				continue
+			}
+			s.Close()
+			expectedIsPortFree = true
+		}
+		start := time.Now()
+		for {
+			isPortFree := ports.IsPortFree(s.Port())
+			logrus.
+				WithField("port", s.Port()).
+				WithField("isFree", isPortFree).
+				WithField("wantToBeFree", expectedIsPortFree).
+				Trace("Check port")
+			if isPortFree == expectedIsPortFree {
+				break
+			}
+			// Safety stop if something went wrong.
+			if time.Since(start) > stopPortChecksAfter {
+				logrus.WithField("expectedIsPortFree", expectedIsPortFree).Warn("Server start/stop check timeouted")
+				break
+			}
+			time.Sleep(recheckPortAfter)
+		}
+	}
+}
+
+// ListenAndServe starts the server and keeps it on based on internet
+// availability. It also monitors and disconnect users if requested.
+func ListenAndServe(s Server, l listener.Listener) {
+	go monitorDisconnectedUsers(s, l)
+	go monitorInternetConnection(s, l)
+
+	// When starting the Bridge, we don't want to retry to notify user
+	// quickly about the issue. Very probably retry will not help anyway.
+	s.ListenRetryAndServe(0, 0)
+}

internal/serverutil/server_test.go

@@ -15,9 +15,21 @@
 // You should have received a copy of the GNU General Public License
 // along with ProtonMail Bridge.  If not, see <https://www.gnu.org/licenses/>.
 
-package users
+package serverutil
 
-// IsAuthorized returns whether the user has received an Auth from the API yet.
+import (
-func (u *User) IsAuthorized() bool {
+	"testing"
-	return u.isAuthorized
+
+	"github.com/ProtonMail/proton-bridge/internal/serverutil/mocks"
+	"github.com/stretchr/testify/require"
+)
+
+func TestServerTurnOffAndOnAgain(t *testing.T) {
+	r := require.New(t)
+	s := mocks.NewTestServer(12321)
+
+	r.True(s.IsPortFree())
+
+	go ListenAndServe(s, s.EventListener)
+	s.RunServerTests(r)
 }

internal/smtp/bridge.go

@@ -31,7 +31,7 @@ type bridgeUser interface {
 	CheckBridgeLogin(password string) error
 	IsCombinedAddressMode() bool
 	GetAddressID(address string) (string, error)
-	GetTemporaryPMAPIClient() pmapi.Client
+	GetClient() pmapi.Client
 	GetStore() storeUserProvider
 }
 
@@ -51,7 +51,7 @@ func (b *bridgeWrap) GetUser(query string) (bridgeUser, error) {
 	if err != nil {
 		return nil, err
 	}
-	return newBridgeUserWrap(user), nil
+	return newBridgeUserWrap(user), nil //nolint[typecheck] missing methods are inherited
 }
 
 type bridgeUserWrap struct {

internal/smtp/preferences.go

@@ -173,7 +173,7 @@ func (b *sendPreferencesBuilder) withPublicKey(v *crypto.KeyRing) {
 //								| 16 (PGP/MIME),
 //     mimeType: 'text/html' | 'text/plain' | 'multipart/mixed',
 //     publicKey: OpenPGPKey | undefined/null
-// }
+// }.
 func (b *sendPreferencesBuilder) build() (p SendPreferences) {
 	p.Encrypt = b.shouldEncrypt()
 	p.Sign = b.shouldSign()
@@ -492,6 +492,8 @@ func (b *sendPreferencesBuilder) setEncryptionPreferences(mailSettings pmapi.Mai
 		b.withSchemeDefault(pgpInline)
 	case pmapi.PGPMIMEPackage:
 		b.withSchemeDefault(pgpMIME)
+	case pmapi.ClearMIMEPackage, pmapi.ClearPackage, pmapi.EncryptedOutsidePackage, pmapi.InternalPackage:
+		// nothing to set
 	}
 
 	// Its value is constrained by the sign flag and the PGP scheme:

internal/smtp/send_recorder.go

@@ -18,6 +18,7 @@
 package smtp
 
 import (
+	"context"
 	"crypto/sha256"
 	"fmt"
 	"strings"
@@ -28,7 +29,7 @@ import (
 )
 
 type messageGetter interface {
-	GetMessage(string) (*pmapi.Message, error)
+	GetMessage(context.Context, string) (*pmapi.Message, error)
 }
 
 type sendRecorderValue struct {
@@ -126,7 +127,7 @@ func (q *sendRecorder) isSendingOrSent(client messageGetter, hash string) (isSen
 		return true, false
 	}
 
-	message, err := client.GetMessage(value.messageID)
+	message, err := client.GetMessage(context.TODO(), value.messageID)
 	// Message could be deleted or there could be an internet issue or whatever,
 	// so let's assume the message was not sent.
 	if err != nil {

internal/smtp/send_recorder_test.go

@@ -18,6 +18,7 @@
 package smtp
 
 import (
+	"context"
 	"errors"
 	"fmt"
 	"net/mail"
@@ -33,7 +34,7 @@ type testSendRecorderGetMessageMock struct {
 	err     error
 }
 
-func (m *testSendRecorderGetMessageMock) GetMessage(messageID string) (*pmapi.Message, error) {
+func (m *testSendRecorderGetMessageMock) GetMessage(_ context.Context, messageID string) (*pmapi.Message, error) {
 	return m.message, m.err
 }
 

internal/smtp/server.go

@@ -20,29 +20,34 @@ package smtp
 import (
 	"crypto/tls"
 	"fmt"
+	"net"
+	"sync/atomic"
+	"time"
 
 	"github.com/ProtonMail/proton-bridge/internal/bridge"
 	"github.com/ProtonMail/proton-bridge/internal/events"
+	"github.com/ProtonMail/proton-bridge/internal/serverutil"
 	"github.com/ProtonMail/proton-bridge/pkg/listener"
 	"github.com/emersion/go-sasl"
 	goSMTP "github.com/emersion/go-smtp"
 	"github.com/sirupsen/logrus"
 )
 
-type smtpServer struct {
+// Server is Bridge SMTP server implementation.
+type Server struct {
+	panicHandler  panicHandler
+	backend       goSMTP.Backend
 	server        *goSMTP.Server
 	eventListener listener.Listener
+	debug         bool
 	useSSL        bool
+	port          int
+	tls           *tls.Config
+	isRunning     atomic.Value
 }
 
 // NewSMTPServer returns an SMTP server configured with the given options.
-func NewSMTPServer(debug bool, port int, useSSL bool, tls *tls.Config, smtpBackend goSMTP.Backend, eventListener listener.Listener) *smtpServer { //nolint[golint]
+func NewSMTPServer(panicHandler panicHandler, debug bool, port int, useSSL bool, tls *tls.Config, smtpBackend goSMTP.Backend, eventListener listener.Listener) *Server {
-	s := goSMTP.NewServer(smtpBackend)
-	s.Addr = fmt.Sprintf("%v:%v", bridge.Host, port)
-	s.TLSConfig = tls
-	s.Domain = bridge.Host
-	s.AllowInsecureAuth = true
-
 	if debug {
 		fmt.Println("THE LOG WILL CONTAIN **DECRYPTED** MESSAGE DATA")
 		log.Warning("================================================")
@@ -50,13 +55,38 @@ func NewSMTPServer(debug bool, port int, useSSL bool, tls *tls.Config, smtpBacke
 		log.Warning("================================================")
 	}
 
+	server := &Server{
+		panicHandler:  panicHandler,
+		backend:       smtpBackend,
+		eventListener: eventListener,
+		debug:         debug,
+		useSSL:        useSSL,
+		port:          port,
+		tls:           tls,
+	}
+	server.isRunning.Store(false)
+	return server
+}
+
+func (s *Server) HandlePanic()    { s.panicHandler.HandlePanic() }
+func (s *Server) IsRunning() bool { return s.isRunning.Load().(bool) }
+func (s *Server) Port() int       { return s.port }
+
+func newGoSMTPServer(debug bool, smtpBackend goSMTP.Backend, port int, tls *tls.Config) *goSMTP.Server {
+	newSMTP := goSMTP.NewServer(smtpBackend)
+	newSMTP.Addr = fmt.Sprintf("%v:%v", bridge.Host, port)
+	newSMTP.TLSConfig = tls
+	newSMTP.Domain = bridge.Host
+	newSMTP.AllowInsecureAuth = true
+	newSMTP.MaxLineLength = 1 << 16
+
 	if debug {
-		s.Debug = logrus.
+		newSMTP.Debug = logrus.
 			WithField("pkg", "smtp/server").
 			WriterLevel(logrus.DebugLevel)
 	}
 
-	s.EnableAuth(sasl.Login, func(conn *goSMTP.Conn) sasl.Server {
+	newSMTP.EnableAuth(sasl.Login, func(conn *goSMTP.Conn) sasl.Server {
 		return sasl.NewLoginServer(func(address, password string) error {
 			user, err := conn.Server().Backend.Login(nil, address, password)
 			if err != nil {
@@ -67,57 +97,92 @@ func NewSMTPServer(debug bool, port int, useSSL bool, tls *tls.Config, smtpBacke
 			return nil
 		})
 	})
-
+	return newSMTP
-	return &smtpServer{
-		server:        s,
-		eventListener: eventListener,
-		useSSL:        useSSL,
-	}
 }
 
-// Starts the server.
+// ListenAndServe starts the server and keeps it on based on internet
-func (s *smtpServer) ListenAndServe() {
+// availability.
-	go s.monitorDisconnectedUsers()
+func (s *Server) ListenAndServe() {
-	l := log.WithField("useSSL", s.useSSL).WithField("address", s.server.Addr)
+	serverutil.ListenAndServe(s, s.eventListener)
+}
 
-	l.Info("SMTP server is starting")
+func (s *Server) ListenRetryAndServe(retries int, retryAfter time.Duration) {
-	var err error
+	if s.IsRunning() {
-	if s.useSSL {
-		err = s.server.ListenAndServeTLS()
-	} else {
-		err = s.server.ListenAndServe()
-	}
-	if err != nil {
-		s.eventListener.Emit(events.ErrorEvent, "SMTP failed: "+err.Error())
-		l.Error("SMTP failed: ", err)
 		return
 	}
-	defer s.server.Close() //nolint[errcheck]
+	s.isRunning.Store(true)
 
-	l.Info("SMTP server stopped")
+	s.server = newGoSMTPServer(s.debug, s.backend, s.port, s.tls)
+
+	l := log.WithField("useSSL", s.useSSL).WithField("address", s.server.Addr)
+	l.Info("SMTP server is starting")
+
+	var listener net.Listener
+	var err error
+	if s.useSSL {
+		listener, err = tls.Listen("tcp", s.server.Addr, s.server.TLSConfig)
+	} else {
+		listener, err = net.Listen("tcp", s.server.Addr)
+	}
+	l.WithError(err).Debug("Listener for SMTP created")
+	if err != nil {
+		s.isRunning.Store(false)
+		if retries > 0 {
+			l.WithError(err).WithField("retries", retries).Warn("SMTP listener failed")
+			time.Sleep(retryAfter)
+			s.ListenRetryAndServe(retries-1, retryAfter)
+			return
+		}
+
+		l.WithError(err).Error("SMTP listener failed")
+		s.eventListener.Emit(events.ErrorEvent, "SMTP failed: "+err.Error())
+		return
+	}
+
+	err = s.server.Serve(listener)
+	l.WithError(err).Debug("GoSMTP not serving")
+	// Serve returns error every time, even after closing the server.
+	// User shouldn't be notified about error if server shouldn't be running,
+	// but it should in case it was not closed by `s.Close()`.
+	if err != nil && s.IsRunning() {
+		s.isRunning.Store(false)
+		l.WithError(err).Error("SMTP server failed")
+		s.eventListener.Emit(events.ErrorEvent, "SMTP failed: "+err.Error())
+		return
+	}
+	defer func() {
+		// Go SMTP server instance can be closed only once. Otherwise
+		// it returns an error. The error is not export therefore we
+		// will check the string value.
+		err := s.server.Close()
+		if err == nil || err.Error() != "smtp: server already closed" {
+			l.WithError(err).Warn("Server was not closed")
+		}
+	}()
+
+	l.Info("SMTP server closed")
 }
 
-// Stops the server.
+// Close stops the server.
-func (s *smtpServer) Close() {
+func (s *Server) Close() {
+	if !s.IsRunning() {
+		return
+	}
+	s.isRunning.Store(false)
+
 	if err := s.server.Close(); err != nil {
-		log.WithError(err).Error("Failed to close the connection")
+		log.WithError(err).Error("Cannot close the server")
 	}
 }
 
-func (s *smtpServer) monitorDisconnectedUsers() {
+func (s *Server) DisconnectUser(address string) {
-	ch := make(chan string)
+	log.Info("Disconnecting all open SMTP connections for ", address)
-	s.eventListener.Add(events.CloseConnectionEvent, ch)
+	s.server.ForEachConn(func(conn *goSMTP.Conn) {
-
+		connUser := conn.Session()
-	for address := range ch {
+		if connUser != nil {
-		log.Info("Disconnecting all open SMTP connections for ", address)
+			if err := conn.Close(); err != nil {
-		disconnectUser := func(conn *goSMTP.Conn) {
+				log.WithError(err).Error("Failed to close the connection")
-			connUser := conn.Session()
-			if connUser != nil {
-				if err := conn.Close(); err != nil {
-					log.WithError(err).Error("Failed to close the connection")
-				}
 			}
 		}
-		s.server.ForEachConn(disconnectUser)
+	})
-	}
 }

internal/smtp/server_test.go

@@ -15,29 +15,29 @@
 // You should have received a copy of the GNU General Public License
 // along with ProtonMail Bridge.  If not, see <https://www.gnu.org/licenses/>.
 
-package pmapi
+package smtp
 
 import (
-	"net/url"
+	"testing"
+
+	"github.com/ProtonMail/proton-bridge/internal/serverutil/mocks"
+
+	"github.com/stretchr/testify/require"
 )
 
-// SendSimpleMetric makes a simple GET request to send a simple metrics report.
+func TestSMTPServerTurnOffAndOnAgain(t *testing.T) {
-func (c *client) SendSimpleMetric(category, action, label string) (err error) {
+	r := require.New(t)
-	v := url.Values{}
+	ts := mocks.NewTestServer(12342)
-	v.Set("Category", category)
-	v.Set("Action", action)
-	v.Set("Label", label)
 
-	req, err := c.NewRequest("GET", "/metrics?"+v.Encode(), nil)
+	s := &Server{
-	if err != nil {
+		panicHandler:  ts.PanicHandler,
-		return
+		port:          ts.WantPort,
+		eventListener: ts.EventListener,
 	}
+	s.isRunning.Store(false)
 
-	var res Res
+	r.True(ts.IsPortFree())
-	if err = c.DoJSON(req, &res); err != nil {
-		return
-	}
 
-	err = res.Err()
+	go s.ListenAndServe()
-	return
+	ts.RunServerTests(r)
 }

internal/smtp/user.go

@@ -21,10 +21,10 @@ package smtp
 
 import (
 	"bytes"
+	"context"
 	"encoding/base64"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"mime"
 	"net/mail"
 	"strings"
@@ -81,7 +81,7 @@ func newSMTPUser(
 
 // This method should eventually no longer be necessary. Everything should go via store.
 func (su *smtpUser) client() pmapi.Client {
-	return su.user.GetTemporaryPMAPIClient()
+	return su.user.GetClient()
 }
 
 // Send sends an email from the given address to the given addresses with the given body.
@@ -123,7 +123,7 @@ func (su *smtpUser) getSendPreferences(
 }
 
 func (su *smtpUser) getContactVCardData(recipient string) (meta *ContactMetadata, err error) {
-	emails, err := su.client().GetContactEmailByEmail(recipient, 0, 1000)
+	emails, err := su.client().GetContactEmailByEmail(context.TODO(), recipient, 0, 1000)
 	if err != nil {
 		return
 	}
@@ -135,7 +135,7 @@ func (su *smtpUser) getContactVCardData(recipient string) (meta *ContactMetadata
 		}
 
 		var contact pmapi.Contact
-		if contact, err = su.client().GetContactByID(email.ContactID); err != nil {
+		if contact, err = su.client().GetContactByID(context.TODO(), email.ContactID); err != nil {
 			return
 		}
 
@@ -151,7 +151,7 @@ func (su *smtpUser) getContactVCardData(recipient string) (meta *ContactMetadata
 }
 
 func (su *smtpUser) getAPIKeyData(recipient string) (apiKeys []pmapi.PublicKey, isInternal bool, err error) {
-	return su.client().GetPublicKeysForEmail(recipient)
+	return su.client().GetPublicKeysForEmail(context.TODO(), recipient)
 }
 
 // Discard currently processed message.
@@ -219,7 +219,7 @@ func (su *smtpUser) Send(returnPath string, to []string, messageReader io.Reader
 
 	messageReader = io.TeeReader(messageReader, b)
 
-	mailSettings, err := su.client().GetMailSettings()
+	mailSettings, err := su.client().GetMailSettings(context.TODO())
 	if err != nil {
 		return err
 	}
@@ -325,12 +325,6 @@ func (su *smtpUser) Send(returnPath string, to []string, messageReader io.Reader
 		return nil
 	}
 
-	if ok, err := su.isTotalSizeOkay(message, attReaders); err != nil {
-		return err
-	} else if !ok {
-		return errors.New("message is too large")
-	}
-
 	su.backend.sendRecorder.addMessage(sendRecorderMessageHash)
 	message, atts, err := su.storeUser.CreateDraft(kr, message, attReaders, attachedPublicKey, attachedPublicKeyName, parentID)
 	if err != nil {
@@ -346,7 +340,7 @@ func (su *smtpUser) Send(returnPath string, to []string, messageReader io.Reader
 	// can lead to sending the wrong message. Also clients do not necessarily
 	// delete the old draft.
 	if draftID != "" {
-		if err := su.client().DeleteMessages([]string{draftID}); err != nil {
+		if err := su.client().DeleteMessages(context.TODO(), []string{draftID}); err != nil {
 			log.WithError(err).WithField("draftID", draftID).Warn("Original draft cannot be deleted")
 		}
 	}
@@ -400,7 +394,7 @@ func (su *smtpUser) Send(returnPath string, to []string, messageReader io.Reader
 			return errors.New("error decoding subject message " + message.Header.Get("Subject"))
 		}
 		if !su.continueSendingUnencryptedMail(subject) {
-			if err := su.client().DeleteMessages([]string{message.ID}); err != nil {
+			if err := su.client().DeleteMessages(context.TODO(), []string{message.ID}); err != nil {
 				log.WithError(err).Warn("Failed to delete canceled messages")
 			}
 			return errors.New("sending was canceled by user")
@@ -429,7 +423,7 @@ func (su *smtpUser) handleReferencesHeader(m *pmapi.Message) (draftID, parentID
 				if su.addressID != "" {
 					filter.AddressID = su.addressID
 				}
-				metadata, _, _ := su.client().ListMessages(filter)
+				metadata, _, _ := su.client().ListMessages(context.TODO(), filter)
 				for _, m := range metadata {
 					if m.IsDraft() {
 						draftID = m.ID
@@ -449,7 +443,7 @@ func (su *smtpUser) handleReferencesHeader(m *pmapi.Message) (draftID, parentID
 		if su.addressID != "" {
 			filter.AddressID = su.addressID
 		}
-		metadata, _, _ := su.client().ListMessages(filter)
+		metadata, _, _ := su.client().ListMessages(context.TODO(), filter)
 		// There can be two or messages with the same external ID and then we cannot
 		// be sure which message should be parent. Better to not choose any.
 		if len(metadata) == 1 {
@@ -541,24 +535,3 @@ func (su *smtpUser) Logout() error {
 	log.Debug("SMTP client logged out user ", su.addressID)
 	return nil
 }
-
-func (su *smtpUser) isTotalSizeOkay(message *pmapi.Message, attReaders []io.Reader) (bool, error) {
-	maxUpload, err := su.storeUser.GetMaxUpload()
-	if err != nil {
-		return false, err
-	}
-
-	var attSize int64
-
-	for i := range attReaders {
-		b, err := ioutil.ReadAll(attReaders[i])
-		if err != nil {
-			return false, err
-		}
-
-		attSize += int64(len(b))
-		attReaders[i] = bytes.NewBuffer(b)
-	}
-
-	return message.Size+attSize <= maxUpload, nil
-}

internal/store/address.go

@@ -90,7 +90,7 @@ func getLabelPrefix(l *pmapi.Label) string {
 	switch {
 	case pmapi.IsSystemLabel(l.ID):
 		return ""
-	case l.Exclusive == 1:
+	case bool(l.Exclusive):
 		return UserFoldersPrefix
 	default:
 		return UserLabelsPrefix

internal/store/change_test.go

@@ -37,8 +37,8 @@ func TestNotifyChangeCreateOrUpdateMessage(t *testing.T) {
 	m.newStoreNoEvents(true)
 	m.store.SetChangeNotifier(m.changeNotifier)
 
-	insertMessage(t, m, "msg1", "Test message 1", addrID1, 0, []string{pmapi.AllMailLabel})
+	insertMessage(t, m, "msg1", "Test message 1", addrID1, false, []string{pmapi.AllMailLabel})
-	insertMessage(t, m, "msg2", "Test message 2", addrID1, 0, []string{pmapi.AllMailLabel})
+	insertMessage(t, m, "msg2", "Test message 2", addrID1, false, []string{pmapi.AllMailLabel})
 }
 
 func TestNotifyChangeCreateOrUpdateMessages(t *testing.T) {
@@ -52,8 +52,8 @@ func TestNotifyChangeCreateOrUpdateMessages(t *testing.T) {
 	m.newStoreNoEvents(true)
 	m.store.SetChangeNotifier(m.changeNotifier)
 
-	msg1 := getTestMessage("msg1", "Test message 1", addrID1, 0, []string{pmapi.AllMailLabel})
+	msg1 := getTestMessage("msg1", "Test message 1", addrID1, false, []string{pmapi.AllMailLabel})
-	msg2 := getTestMessage("msg2", "Test message 2", addrID1, 0, []string{pmapi.AllMailLabel})
+	msg2 := getTestMessage("msg2", "Test message 2", addrID1, false, []string{pmapi.AllMailLabel})
 	require.Nil(t, m.store.createOrUpdateMessagesEvent([]*pmapi.Message{msg1, msg2}))
 }
 
@@ -63,8 +63,8 @@ func TestNotifyChangeDeleteMessage(t *testing.T) {
 
 	m.newStoreNoEvents(true)
 
-	insertMessage(t, m, "msg1", "Test message 1", addrID1, 0, []string{pmapi.AllMailLabel})
+	insertMessage(t, m, "msg1", "Test message 1", addrID1, false, []string{pmapi.AllMailLabel})
-	insertMessage(t, m, "msg2", "Test message 2", addrID1, 0, []string{pmapi.AllMailLabel})
+	insertMessage(t, m, "msg2", "Test message 2", addrID1, false, []string{pmapi.AllMailLabel})
 
 	m.changeNotifier.EXPECT().DeleteMessage(addr1, "All Mail", uint32(2))
 	m.changeNotifier.EXPECT().DeleteMessage(addr1, "All Mail", uint32(1))

internal/store/event_loop.go

@@ -18,6 +18,7 @@
 package store
 
 import (
+	"context"
 	"math/rand"
 	"time"
 
@@ -80,7 +81,7 @@ func (loop *eventLoop) client() pmapi.Client {
 func (loop *eventLoop) setFirstEventID() (err error) {
 	loop.log.Info("Setting first event ID")
 
-	event, err := loop.client().GetEvent("")
+	event, err := loop.client().GetEvent(context.Background(), "")
 	if err != nil {
 		loop.log.WithError(err).Error("Could not get latest event ID")
 		return
@@ -99,6 +100,11 @@ func (loop *eventLoop) setFirstEventID() (err error) {
 // pollNow starts polling events right away and waits till the events are
 // processed so we are sure updates are propagated to the database.
 func (loop *eventLoop) pollNow() {
+	// When event loop is not running, it would cause infinite wait.
+	if !loop.isRunning {
+		return
+	}
+
 	eventProcessedCh := make(chan struct{})
 	loop.pollCh <- eventProcessedCh
 	<-eventProcessedCh
@@ -156,6 +162,7 @@ func (loop *eventLoop) loop() {
 			return
 		case <-t.C:
 			// Randomise periodic calls within range pollInterval ± pollSpread to reduces potential load spikes on API.
+			//nolint[gosec] It is OK to use weaker random number generator here
 			time.Sleep(time.Duration(rand.Intn(2*int(pollIntervalSpread.Milliseconds()))) * time.Millisecond)
 		case eventProcessedCh = <-loop.pollCh:
 			// We don't want to wait here. Polling should happen instantly.
@@ -215,7 +222,7 @@ func (loop *eventLoop) processNextEvent() (more bool, err error) { // nolint[fun
 	// We only want to consider invalid tokens as real errors because all other errors might fix themselves eventually
 	// (e.g. no internet, ulimit reached etc.)
 	defer func() {
-		if errors.Cause(err) == pmapi.ErrAPINotReachable {
+		if errors.Cause(err) == pmapi.ErrNoConnection {
 			l.Warn("Internet unavailable")
 			err = nil
 		}
@@ -231,13 +238,12 @@ func (loop *eventLoop) processNextEvent() (more bool, err error) { // nolint[fun
 			err = nil
 		}
 
-		_, errUnauthorized := errors.Cause(err).(*pmapi.ErrUnauthorized)
-
 		if err == nil {
 			loop.errCounter = 0
 		}
-		// All errors except Invalid Token (which is not possible to recover from) are ignored.
+
-		if err != nil && !errUnauthorized && errors.Cause(err) != pmapi.ErrInvalidToken {
+		// All errors except ErrUnauthorized (which is not possible to recover from) are ignored.
+		if err != nil && errors.Cause(err) != pmapi.ErrUnauthorized {
 			l.WithError(err).WithField("errors", loop.errCounter).Error("Error skipped")
 			loop.errCounter++
 			if loop.errCounter == errMaxSentry {
@@ -258,7 +264,7 @@ func (loop *eventLoop) processNextEvent() (more bool, err error) { // nolint[fun
 	loop.pollCounter++
 
 	var event *pmapi.Event
-	if event, err = loop.client().GetEvent(loop.currentEventID); err != nil {
+	if event, err = loop.client().GetEvent(context.Background(), loop.currentEventID); err != nil {
 		return false, errors.Wrap(err, "failed to get event")
 	}
 
@@ -268,8 +274,6 @@ func (loop *eventLoop) processNextEvent() (more bool, err error) { // nolint[fun
 		return false, errors.New("received empty event")
 	}
 
-	l = l.WithField("newEventID", event.EventID)
-
 	if err = loop.processEvent(event); err != nil {
 		return false, errors.Wrap(err, "failed to process event")
 	}
@@ -287,7 +291,7 @@ func (loop *eventLoop) processNextEvent() (more bool, err error) { // nolint[fun
 		}
 	}
 
-	return event.More == 1, err
+	return bool(event.More), err
 }
 
 func (loop *eventLoop) processEvent(event *pmapi.Event) (err error) {
@@ -346,7 +350,7 @@ func (loop *eventLoop) processAddresses(log *logrus.Entry, addressEvents []*pmap
 	// Get old addresses for comparisons before updating user.
 	oldList := loop.client().Addresses()
 
-	if err = loop.user.UpdateUser(); err != nil {
+	if err = loop.user.UpdateUser(context.Background()); err != nil {
 		if logoutErr := loop.user.Logout(); logoutErr != nil {
 			log.WithError(logoutErr).Error("Failed to logout user after failed update")
 		}
@@ -383,6 +387,8 @@ func (loop *eventLoop) processAddresses(log *logrus.Entry, addressEvents []*pmap
 			log.WithField("email", email).Debug("Address was deleted")
 			loop.user.CloseConnection(email)
 			loop.events.Emit(bridgeEvents.AddressChangedLogoutEvent, email)
+		case pmapi.EventUpdateFlags:
+			log.Error("EventUpdateFlags for address event is uknown operation")
 		}
 	}
 
@@ -411,6 +417,8 @@ func (loop *eventLoop) processLabels(eventLog *logrus.Entry, labels []*pmapi.Eve
 			if err := loop.store.deleteMailboxEvent(eventLabel.ID); err != nil {
 				return errors.Wrap(err, "failed to delete label")
 			}
+		case pmapi.EventUpdateFlags:
+			log.Error("EventUpdateFlags for label event is uknown operation")
 		}
 	}
 
@@ -453,8 +461,8 @@ func (loop *eventLoop) processMessages(eventLog *logrus.Entry, messages []*pmapi
 
 				msgLog.WithError(err).Warning("Message was not present in DB. Trying fetch...")
 
-				if msg, err = loop.client().GetMessage(message.ID); err != nil {
+				if msg, err = loop.client().GetMessage(context.Background(), message.ID); err != nil {
-					if _, ok := err.(*pmapi.ErrUnprocessableEntity); ok {
+					if _, ok := err.(pmapi.ErrUnprocessableEntity); ok {
 						msgLog.WithError(err).Warn("Skipping message update because message exists neither in local DB nor on API")
 						err = nil
 						continue

internal/store/event_loop_test.go

@@ -18,6 +18,7 @@
 package store
 
 import (
+	"context"
 	"net/mail"
 	"testing"
 	"time"
@@ -39,17 +40,17 @@ func TestEventLoopProcessMoreEvents(t *testing.T) {
 		// Doesn't matter which IDs are used.
 		// This test is trying to see whether event loop will immediately process
 		// next event if there is `More` of them.
-		m.client.EXPECT().GetEvent("latestEventID").Return(&pmapi.Event{
+		m.client.EXPECT().GetEvent(gomock.Any(), "latestEventID").Return(&pmapi.Event{
 			EventID: "event50",
-			More:    1,
+			More:    true,
 		}, nil),
-		m.client.EXPECT().GetEvent("event50").Return(&pmapi.Event{
+		m.client.EXPECT().GetEvent(gomock.Any(), "event50").Return(&pmapi.Event{
 			EventID: "event70",
-			More:    0,
+			More:    false,
 		}, nil),
-		m.client.EXPECT().GetEvent("event70").Return(&pmapi.Event{
+		m.client.EXPECT().GetEvent(gomock.Any(), "event70").Return(&pmapi.Event{
 			EventID: "event71",
-			More:    0,
+			More:    false,
 		}, nil),
 	)
 	m.newStoreNoEvents(true)
@@ -165,7 +166,7 @@ func TestEventLoopDeletionPaused(t *testing.T) {
 
 func testEvent(t *testing.T, m *mocksForStore, event *pmapi.Event) {
 	eventReceived := make(chan struct{})
-	m.client.EXPECT().GetEvent("latestEventID").DoAndReturn(func(eventID string) (*pmapi.Event, error) {
+	m.client.EXPECT().GetEvent(gomock.Any(), "latestEventID").DoAndReturn(func(_ context.Context, eventID string) (*pmapi.Event, error) {
 		defer close(eventReceived)
 		return event, nil
 	})
@@ -187,7 +188,7 @@ func TestEventLoopUpdateMessage(t *testing.T) {
 	msg := &pmapi.Message{
 		ID:       "msg1",
 		Subject:  "old",
-		Unread:   0,
+		Unread:   false,
 		Flags:    10,
 		Sender:   address1,
 		ToList:   []*mail.Address{address2},
@@ -199,7 +200,7 @@ func TestEventLoopUpdateMessage(t *testing.T) {
 	newMsg := &pmapi.Message{
 		ID:       "msg1",
 		Subject:  "new",
-		Unread:   1,
+		Unread:   true,
 		Flags:    11,
 		Sender:   address2,
 		ToList:   []*mail.Address{address1},

internal/store/mailbox.go

@@ -254,7 +254,7 @@ func (storeMailbox *Mailbox) txGetAPIIDsBucket(tx *bolt.Tx) *bolt.Bucket {
 	return storeMailbox.txGetBucket(tx).Bucket(apiIDsBucket)
 }
 
-// txGetDeletedIDsBucket returns the bucket with messagesID marked as deleted
+// txGetDeletedIDsBucket returns the bucket with messagesID marked as deleted.
 func (storeMailbox *Mailbox) txGetDeletedIDsBucket(tx *bolt.Tx) *bolt.Bucket {
 	return storeMailbox.txGetBucket(tx).Bucket(deletedIDsBucket)
 }

internal/store/mailbox_counts.go

@@ -129,17 +129,10 @@ func (mc *mailboxCounts) getPMLabel() *pmapi.Label {
 		Color:     mc.Color,
 		Order:     mc.Order,
 		Type:      pmapi.LabelTypeMailbox,
-		Exclusive: mc.isExclusive(),
+		Exclusive: pmapi.Boolean(mc.IsFolder),
 	}
 }
 
-func (mc *mailboxCounts) isExclusive() int {
-	if mc.IsFolder {
-		return 1
-	}
-	return 0
-}
-
 // createOrUpdateMailboxCountsBuckets will not change the on-API-counts.
 func (store *Store) createOrUpdateMailboxCountsBuckets(labels []*pmapi.Label) error {
 	// Don't forget about system folders.
@@ -162,7 +155,7 @@ func (store *Store) createOrUpdateMailboxCountsBuckets(labels []*pmapi.Label) er
 			mailbox.LabelName = label.Path
 			mailbox.Color = label.Color
 			mailbox.Order = label.Order
-			mailbox.IsFolder = label.Exclusive == 1
+			mailbox.IsFolder = bool(label.Exclusive)
 
 			// Write.
 			if err = mailbox.txWriteToBucket(countsBkt); err != nil {

internal/store/mailbox_counts_test.go

@@ -75,7 +75,7 @@ func TestMailboxNames(t *testing.T) {
 		newLabel(100, "labelID1", "Label1"),
 		newLabel(1000, "folderID1", "Folder1"),
 	}
-	foldersAndLabels[1].Exclusive = 1
+	foldersAndLabels[1].Exclusive = true
 
 	for _, counts := range getSystemFolders() {
 		foldersAndLabels = append(foldersAndLabels, counts.getPMLabel())

internal/store/mailbox_ids.go

@@ -36,23 +36,41 @@ import (
 func (storeMailbox *Mailbox) GetAPIIDsFromUIDRange(start, stop uint32) (apiIDs []string, err error) {
 	err = storeMailbox.db().View(func(tx *bolt.Tx) error {
 		b := storeMailbox.txGetIMAPIDsBucket(tx)
+		c := b.Cursor()
 
+		// GODT-1153 If the mailbox is empty we should reply BAD to client.
+		if uid, _ := c.Last(); uid == nil {
+			return nil
+		}
+
+		// If the start range is a wildcard, the range can only refer to the last message in the mailbox.
+		if start == 0 {
+			_, apiID := c.Last()
+			apiIDs = append(apiIDs, string(apiID))
+			return nil
+		}
+
+		// Resolve the stop value to be the final UID in the mailbox.
 		if stop == 0 {
-			// A null stop means no stop.
+			stop = storeMailbox.txGetFinalUID(b)
-			stop = ^uint32(0)
+		}
+
+		// After resolving the stop value, it might be less than start so we sort it.
+		if start > stop {
+			start, stop = stop, start
 		}
 
 		startb := itob(start)
 		stopb := itob(stop)
 
-		c := b.Cursor()
 		for k, v := c.Seek(startb); k != nil && bytes.Compare(k, stopb) <= 0; k, v = c.Next() {
 			apiIDs = append(apiIDs, string(v))
 		}
 
 		return nil
 	})
-	return
+
+	return apiIDs, err
 }
 
 // GetAPIIDsFromSequenceRange returns API IDs by IMAP sequence number range.
@@ -60,28 +78,52 @@ func (storeMailbox *Mailbox) GetAPIIDsFromSequenceRange(start, stop uint32) (api
 	err = storeMailbox.db().View(func(tx *bolt.Tx) error {
 		b := storeMailbox.txGetIMAPIDsBucket(tx)
 		c := b.Cursor()
+
+		// GODT-1153 If the mailbox is empty we should reply BAD to client.
+		if uid, _ := c.Last(); uid == nil {
+			return nil
+		}
+
+		// If the start range is a wildcard, the range can only refer to the last message in the mailbox.
+		if start == 0 {
+			_, apiID := c.Last()
+			apiIDs = append(apiIDs, string(apiID))
+			return nil
+		}
+
 		var i uint32
+
 		for k, v := c.First(); k != nil; k, v = c.Next() {
 			i++
+
 			if i < start {
 				continue
 			}
+
 			if stop > 0 && i > stop {
 				break
 			}
+
 			apiIDs = append(apiIDs, string(v))
 		}
+
+		if stop == 0 && len(apiIDs) == 0 {
+			if _, apiID := c.Last(); len(apiID) > 0 {
+				apiIDs = append(apiIDs, string(apiID))
+			}
+		}
+
 		return nil
 	})
-	return
+
+	return apiIDs, err
 }
 
 // GetLatestAPIID returns the latest message API ID which still exists.
 // Info: not the latest IMAP UID which can be already removed.
 func (storeMailbox *Mailbox) GetLatestAPIID() (apiID string, err error) {
 	err = storeMailbox.db().View(func(tx *bolt.Tx) error {
-		b := storeMailbox.txGetAPIIDsBucket(tx)
+		c := storeMailbox.txGetAPIIDsBucket(tx).Cursor()
-		c := b.Cursor()
 		lastAPIID, _ := c.Last()
 		apiID = string(lastAPIID)
 		if apiID == "" {
@@ -283,3 +325,13 @@ func (storeMailbox *Mailbox) GetUIDByHeader(header *mail.Header) (foundUID uint3
 
 	return foundUID
 }
+
+func (storeMailbox *Mailbox) txGetFinalUID(b *bolt.Bucket) uint32 {
+	uid, _ := b.Cursor().Last()
+
+	if uid == nil {
+		panic(errors.New("cannot get final UID of empty mailbox"))
+	}
+
+	return btoi(uid)
+}

internal/store/mailbox_ids_test.go

@@ -37,10 +37,10 @@ func TestGetSequenceNumberAndGetUID(t *testing.T) {
 
 	m.newStoreNoEvents(true)
 
-	insertMessage(t, m, "msg1", "Test message 1", addrID1, 0, []string{pmapi.AllMailLabel, pmapi.InboxLabel})
+	insertMessage(t, m, "msg1", "Test message 1", addrID1, false, []string{pmapi.AllMailLabel, pmapi.InboxLabel})
-	insertMessage(t, m, "msg2", "Test message 2", addrID1, 0, []string{pmapi.AllMailLabel, pmapi.ArchiveLabel})
+	insertMessage(t, m, "msg2", "Test message 2", addrID1, false, []string{pmapi.AllMailLabel, pmapi.ArchiveLabel})
-	insertMessage(t, m, "msg3", "Test message 3", addrID1, 0, []string{pmapi.AllMailLabel, pmapi.InboxLabel})
+	insertMessage(t, m, "msg3", "Test message 3", addrID1, false, []string{pmapi.AllMailLabel, pmapi.InboxLabel})
-	insertMessage(t, m, "msg4", "Test message 4", addrID1, 0, []string{pmapi.AllMailLabel})
+	insertMessage(t, m, "msg4", "Test message 4", addrID1, false, []string{pmapi.AllMailLabel})
 
 	checkAllMessageIDs(t, m, []string{"msg1", "msg2", "msg3", "msg4"})
 
@@ -56,7 +56,7 @@ func checkMailboxMessageIDs(t *testing.T, m *mocksForStore, mailboxLabel string,
 	storeAddress := m.store.addresses[addrID1]
 	storeMailbox := storeAddress.mailboxes[mailboxLabel]
 
-	ids, err := storeMailbox.GetAPIIDsFromSequenceRange(0, uint32(len(wantIDs)))
+	ids, err := storeMailbox.GetAPIIDsFromSequenceRange(1, uint32(len(wantIDs)))
 	require.Nil(t, err)
 
 	idx := 0
@@ -82,20 +82,20 @@ func TestGetUIDByHeader(t *testing.T) { //nolint[funlen]
 
 	m.newStoreNoEvents(true)
 
-	tstMsg := getTestMessage("msg1", "Without external ID", addrID1, 0, []string{pmapi.AllMailLabel, pmapi.SentLabel})
+	tstMsg := getTestMessage("msg1", "Without external ID", addrID1, false, []string{pmapi.AllMailLabel, pmapi.SentLabel})
 	require.Nil(t, m.store.createOrUpdateMessageEvent(tstMsg))
 
-	tstMsg = getTestMessage("msg2", "External ID with spaces", addrID1, 0, []string{pmapi.AllMailLabel, pmapi.SentLabel})
+	tstMsg = getTestMessage("msg2", "External ID with spaces", addrID1, false, []string{pmapi.AllMailLabel, pmapi.SentLabel})
 	tstMsg.ExternalID = "   externalID-non-pm-com "
 	require.Nil(t, m.store.createOrUpdateMessageEvent(tstMsg))
 
-	tstMsg = getTestMessage("msg3", "External ID with <>", addrID1, 0, []string{pmapi.AllMailLabel, pmapi.SentLabel})
+	tstMsg = getTestMessage("msg3", "External ID with <>", addrID1, false, []string{pmapi.AllMailLabel, pmapi.SentLabel})
 	tstMsg.ExternalID = "<externalID@pm.me>"
 	tstMsg.Header = mail.Header{"References": []string{"wrongID", "externalID-non-pm-com", "msg2"}}
 	require.Nil(t, m.store.createOrUpdateMessageEvent(tstMsg))
 
 	// Not sure if this is a real-world scenario but we should be able to address this properly.
-	tstMsg = getTestMessage("msg4", "External ID with <> and spaces and special characters", addrID1, 0, []string{pmapi.AllMailLabel, pmapi.SentLabel})
+	tstMsg = getTestMessage("msg4", "External ID with <> and spaces and special characters", addrID1, false, []string{pmapi.AllMailLabel, pmapi.SentLabel})
 	tstMsg.ExternalID = "   <   external.()+*[]ID@another.pm.me    >    "
 	require.Nil(t, m.store.createOrUpdateMessageEvent(tstMsg))
 

internal/store/mailbox_message.go

@@ -25,7 +25,7 @@ import (
 )
 
 // ErrAllMailOpNotAllowed is error user when user tries to do unsupported
-// operation on All Mail folder
+// operation on All Mail folder.
 var ErrAllMailOpNotAllowed = errors.New("operation not allowed for 'All Mail' folder")
 
 // GetMessage returns the `pmapi.Message` struct wrapped in `StoreMessage`
@@ -41,7 +41,7 @@ func (storeMailbox *Mailbox) GetMessage(apiID string) (*Message, error) {
 // FetchMessage fetches the message with the given `apiID`, stores it in the database, and returns a new store message
 // wrapping it.
 func (storeMailbox *Mailbox) FetchMessage(apiID string) (*Message, error) {
-	msg, err := storeMailbox.client().GetMessage(apiID)
+	msg, err := storeMailbox.client().GetMessage(exposeContextForIMAP(), apiID)
 	if err != nil {
 		return nil, err
 	}
@@ -58,19 +58,25 @@ func (storeMailbox *Mailbox) ImportMessage(msg *pmapi.Message, body []byte, labe
 	}
 
 	importReqs := &pmapi.ImportMsgReq{
-		AddressID: msg.AddressID,
+		Metadata: &pmapi.ImportMetadata{
-		Body:      body,
+			AddressID: msg.AddressID,
-		Unread:    msg.Unread,
+			Unread:    msg.Unread,
-		Flags:     msg.Flags,
+			Flags:     msg.Flags,
-		Time:      msg.Time,
+			Time:      msg.Time,
-		LabelIDs:  labelIDs,
+			LabelIDs:  labelIDs,
+		},
+		Message: body,
 	}
 
-	res, err := storeMailbox.client().Import([]*pmapi.ImportMsgReq{importReqs})
+	res, err := storeMailbox.client().Import(exposeContextForIMAP(), pmapi.ImportMsgReqs{importReqs})
-	if err == nil && len(res) > 0 {
+	if err != nil {
-		msg.ID = res[0].MessageID
+		return err
 	}
-	return err
+	if len(res) == 0 {
+		return errors.New("no import response")
+	}
+	msg.ID = res[0].MessageID
+	return res[0].Error
 }
 
 // LabelMessages adds the label by calling an API.
@@ -91,7 +97,7 @@ func (storeMailbox *Mailbox) LabelMessages(apiIDs []string) error {
 		return ErrAllMailOpNotAllowed
 	}
 	defer storeMailbox.pollNow()
-	return storeMailbox.client().LabelMessages(apiIDs, storeMailbox.labelID)
+	return storeMailbox.client().LabelMessages(exposeContextForIMAP(), apiIDs, storeMailbox.labelID)
 }
 
 // UnlabelMessages removes the label by calling an API.
@@ -104,7 +110,7 @@ func (storeMailbox *Mailbox) UnlabelMessages(apiIDs []string) error {
 		return ErrAllMailOpNotAllowed
 	}
 	defer storeMailbox.pollNow()
-	return storeMailbox.client().UnlabelMessages(apiIDs, storeMailbox.labelID)
+	return storeMailbox.client().UnlabelMessages(exposeContextForIMAP(), apiIDs, storeMailbox.labelID)
 }
 
 // MarkMessagesRead marks the message read by calling an API.
@@ -124,14 +130,14 @@ func (storeMailbox *Mailbox) MarkMessagesRead(apiIDs []string) error {
 	// Therefore we do not issue API update if the message is already read.
 	ids := []string{}
 	for _, apiID := range apiIDs {
-		if message, _ := storeMailbox.store.getMessageFromDB(apiID); message == nil || message.Unread == 1 {
+		if message, _ := storeMailbox.store.getMessageFromDB(apiID); message == nil || message.Unread {
 			ids = append(ids, apiID)
 		}
 	}
 	if len(ids) == 0 {
 		return nil
 	}
-	return storeMailbox.client().MarkMessagesRead(ids)
+	return storeMailbox.client().MarkMessagesRead(exposeContextForIMAP(), ids)
 }
 
 // MarkMessagesUnread marks the message unread by calling an API.
@@ -143,7 +149,7 @@ func (storeMailbox *Mailbox) MarkMessagesUnread(apiIDs []string) error {
 		"mailbox":  storeMailbox.Name,
 	}).Trace("Marking messages as unread")
 	defer storeMailbox.pollNow()
-	return storeMailbox.client().MarkMessagesUnread(apiIDs)
+	return storeMailbox.client().MarkMessagesUnread(exposeContextForIMAP(), apiIDs)
 }
 
 // MarkMessagesStarred adds the Starred label by calling an API.
@@ -156,7 +162,7 @@ func (storeMailbox *Mailbox) MarkMessagesStarred(apiIDs []string) error {
 		"mailbox":  storeMailbox.Name,
 	}).Trace("Marking messages as starred")
 	defer storeMailbox.pollNow()
-	return storeMailbox.client().LabelMessages(apiIDs, pmapi.StarredLabel)
+	return storeMailbox.client().LabelMessages(exposeContextForIMAP(), apiIDs, pmapi.StarredLabel)
 }
 
 // MarkMessagesUnstarred removes the Starred label by calling an API.
@@ -169,11 +175,11 @@ func (storeMailbox *Mailbox) MarkMessagesUnstarred(apiIDs []string) error {
 		"mailbox":  storeMailbox.Name,
 	}).Trace("Marking messages as unstarred")
 	defer storeMailbox.pollNow()
-	return storeMailbox.client().UnlabelMessages(apiIDs, pmapi.StarredLabel)
+	return storeMailbox.client().UnlabelMessages(exposeContextForIMAP(), apiIDs, pmapi.StarredLabel)
 }
 
 // MarkMessagesDeleted adds local flag \Deleted. This is not propagated to API
-// until RemoveDeleted is called
+// until RemoveDeleted is called.
 func (storeMailbox *Mailbox) MarkMessagesDeleted(apiIDs []string) error {
 	log.WithFields(logrus.Fields{
 		"messages": apiIDs,
@@ -253,11 +259,11 @@ func (storeMailbox *Mailbox) RemoveDeleted(apiIDs []string) error {
 		}
 	case pmapi.DraftLabel:
 		storeMailbox.log.WithField("ids", apiIDs).Warn("Deleting drafts")
-		if err := storeMailbox.client().DeleteMessages(apiIDs); err != nil {
+		if err := storeMailbox.client().DeleteMessages(exposeContextForIMAP(), apiIDs); err != nil {
 			return err
 		}
 	default:
-		if err := storeMailbox.client().UnlabelMessages(apiIDs, storeMailbox.labelID); err != nil {
+		if err := storeMailbox.client().UnlabelMessages(exposeContextForIMAP(), apiIDs, storeMailbox.labelID); err != nil {
 			return err
 		}
 	}
@@ -295,13 +301,13 @@ func (storeMailbox *Mailbox) deleteFromTrashOrSpam(apiIDs []string) error {
 		}
 	}
 	if len(messageIDsToUnlabel) > 0 {
-		if err := storeMailbox.client().UnlabelMessages(messageIDsToUnlabel, storeMailbox.labelID); err != nil {
+		if err := storeMailbox.client().UnlabelMessages(exposeContextForIMAP(), messageIDsToUnlabel, storeMailbox.labelID); err != nil {
 			l.WithError(err).Warning("Cannot unlabel before deleting")
 		}
 	}
 	if len(messageIDsToDelete) > 0 {
 		storeMailbox.log.WithField("ids", messageIDsToDelete).Warn("Deleting messages")
-		if err := storeMailbox.client().DeleteMessages(messageIDsToDelete); err != nil {
+		if err := storeMailbox.client().DeleteMessages(exposeContextForIMAP(), messageIDsToDelete); err != nil {
 			return err
 		}
 	}

internal/store/message.go

@@ -18,10 +18,14 @@
 package store
 
 import (
+	"bufio"
+	"bytes"
 	"net/mail"
+	"net/textproto"
 
 	pkgMsg "github.com/ProtonMail/proton-bridge/pkg/message"
 	"github.com/ProtonMail/proton-bridge/pkg/pmapi"
+	"github.com/pkg/errors"
 	bolt "go.etcd.io/bbolt"
 )
 
@@ -64,7 +68,7 @@ func (message *Message) Message() *pmapi.Message {
 }
 
 // IsMarkedDeleted returns true if message is marked as deleted for specific
-// mailbox
+// mailbox.
 func (message *Message) IsMarkedDeleted() bool {
 	isMarkedAsDeleted := false
 	err := message.storeMailbox.db().View(func(tx *bolt.Tx) error {
@@ -103,6 +107,8 @@ func (message *Message) SetSize(size int64) error {
 // header of decrypted message. This should not trigger any IMAP update.
 // NOTE: Content type depends on details of decrypted message which we want to
 // cache.
+//
+// Deprecated: Use SetHeader instead.
 func (message *Message) SetContentTypeAndHeader(mimeType string, header mail.Header) error {
 	message.msg.MIMEType = mimeType
 	message.msg.Header = header
@@ -121,6 +127,57 @@ func (message *Message) SetContentTypeAndHeader(mimeType string, header mail.Hea
 	return message.store.db.Update(txUpdate)
 }
 
+// SetHeader checks header can be parsed and if yes it stores header bytes in
+// database.
+func (message *Message) SetHeader(header []byte) error {
+	_, err := textproto.NewReader(bufio.NewReader(bytes.NewReader(header))).ReadMIMEHeader()
+	if err != nil {
+		return err
+	}
+	return message.store.db.Update(func(tx *bolt.Tx) error {
+		return tx.Bucket(headersBucket).Put([]byte(message.ID()), header)
+	})
+}
+
+// IsFullHeaderCached will check that valid full header is stored in DB.
+func (message *Message) IsFullHeaderCached() bool {
+	header, err := message.getRawHeader()
+	return err == nil && header != nil
+}
+
+func (message *Message) getRawHeader() (raw []byte, err error) {
+	err = message.store.db.View(func(tx *bolt.Tx) error {
+		raw = tx.Bucket(headersBucket).Get([]byte(message.ID()))
+		return nil
+	})
+	return
+}
+
+// GetHeader will return cached header from DB.
+func (message *Message) GetHeader() []byte {
+	raw, err := message.getRawHeader()
+	if err != nil {
+		panic(errors.Wrap(err, "failed to get raw message header"))
+	}
+
+	return raw
+}
+
+// GetMIMEHeader will return cached header from DB, parsed as a textproto.MIMEHeader.
+func (message *Message) GetMIMEHeader() textproto.MIMEHeader {
+	raw, err := message.getRawHeader()
+	if err != nil {
+		panic(errors.Wrap(err, "failed to get raw message header"))
+	}
+
+	header, err := textproto.NewReader(bufio.NewReader(bytes.NewReader(raw))).ReadMIMEHeader()
+	if err != nil {
+		return textproto.MIMEHeader(message.msg.Header)
+	}
+
+	return header
+}
+
 // SetBodyStructure stores serialized body structure in database.
 func (message *Message) SetBodyStructure(bs *pkgMsg.BodyStructure) error {
 	txUpdate := func(tx *bolt.Tx) error {
@@ -148,3 +205,17 @@ func (message *Message) GetBodyStructure() (bs *pkgMsg.BodyStructure, err error)
 	}
 	return bs, nil
 }
+
+func (message *Message) IncreaseBuildCount() (times uint32, err error) {
+	txUpdate := func(tx *bolt.Tx) error {
+		times, err = message.store.txIncreaseMsgBuildCount(
+			tx.Bucket(msgBuildCountBucket),
+			message.ID(),
+		)
+		return err
+	}
+	if err = message.store.db.Update(txUpdate); err != nil {
+		return 0, err
+	}
+	return times, nil
+}

internal/store/mocks/mocks.go

@@ -1,10 +1,11 @@
 // Code generated by MockGen. DO NOT EDIT.
-// Source: github.com/ProtonMail/proton-bridge/internal/store (interfaces: PanicHandler,ClientManager,BridgeUser,ChangeNotifier)
+// Source: github.com/ProtonMail/proton-bridge/internal/store (interfaces: PanicHandler,BridgeUser,ChangeNotifier)
 
 // Package mocks is a generated GoMock package.
 package mocks
 
 import (
+	context "context"
 	reflect "reflect"
 
 	pmapi "github.com/ProtonMail/proton-bridge/pkg/pmapi"
@@ -46,43 +47,6 @@ func (mr *MockPanicHandlerMockRecorder) HandlePanic() *gomock.Call {
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "HandlePanic", reflect.TypeOf((*MockPanicHandler)(nil).HandlePanic))
 }
 
-// MockClientManager is a mock of ClientManager interface
-type MockClientManager struct {
-	ctrl     *gomock.Controller
-	recorder *MockClientManagerMockRecorder
-}
-
-// MockClientManagerMockRecorder is the mock recorder for MockClientManager
-type MockClientManagerMockRecorder struct {
-	mock *MockClientManager
-}
-
-// NewMockClientManager creates a new mock instance
-func NewMockClientManager(ctrl *gomock.Controller) *MockClientManager {
-	mock := &MockClientManager{ctrl: ctrl}
-	mock.recorder = &MockClientManagerMockRecorder{mock}
-	return mock
-}
-
-// EXPECT returns an object that allows the caller to indicate expected use
-func (m *MockClientManager) EXPECT() *MockClientManagerMockRecorder {
-	return m.recorder
-}
-
-// GetClient mocks base method
-func (m *MockClientManager) GetClient(arg0 string) pmapi.Client {
-	m.ctrl.T.Helper()
-	ret := m.ctrl.Call(m, "GetClient", arg0)
-	ret0, _ := ret[0].(pmapi.Client)
-	return ret0
-}
-
-// GetClient indicates an expected call of GetClient
-func (mr *MockClientManagerMockRecorder) GetClient(arg0 interface{}) *gomock.Call {
-	mr.mock.ctrl.T.Helper()
-	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "GetClient", reflect.TypeOf((*MockClientManager)(nil).GetClient), arg0)
-}
-
 // MockBridgeUser is a mock of BridgeUser interface
 type MockBridgeUser struct {
 	ctrl     *gomock.Controller
@@ -145,6 +109,20 @@ func (mr *MockBridgeUserMockRecorder) GetAddressID(arg0 interface{}) *gomock.Cal
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "GetAddressID", reflect.TypeOf((*MockBridgeUser)(nil).GetAddressID), arg0)
 }
 
+// GetClient mocks base method
+func (m *MockBridgeUser) GetClient() pmapi.Client {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "GetClient")
+	ret0, _ := ret[0].(pmapi.Client)
+	return ret0
+}
+
+// GetClient indicates an expected call of GetClient
+func (mr *MockBridgeUserMockRecorder) GetClient() *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "GetClient", reflect.TypeOf((*MockBridgeUser)(nil).GetClient))
+}
+
 // GetPrimaryAddress mocks base method
 func (m *MockBridgeUser) GetPrimaryAddress() string {
 	m.ctrl.T.Helper()
@@ -230,17 +208,17 @@ func (mr *MockBridgeUserMockRecorder) Logout() *gomock.Call {
 }
 
 // UpdateUser mocks base method
-func (m *MockBridgeUser) UpdateUser() error {
+func (m *MockBridgeUser) UpdateUser(arg0 context.Context) error {
 	m.ctrl.T.Helper()
-	ret := m.ctrl.Call(m, "UpdateUser")
+	ret := m.ctrl.Call(m, "UpdateUser", arg0)
 	ret0, _ := ret[0].(error)
 	return ret0
 }
 
 // UpdateUser indicates an expected call of UpdateUser
-func (mr *MockBridgeUserMockRecorder) UpdateUser() *gomock.Call {
+func (mr *MockBridgeUserMockRecorder) UpdateUser(arg0 interface{}) *gomock.Call {
 	mr.mock.ctrl.T.Helper()
-	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "UpdateUser", reflect.TypeOf((*MockBridgeUser)(nil).UpdateUser))
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "UpdateUser", reflect.TypeOf((*MockBridgeUser)(nil).UpdateUser), arg0)
 }
 
 // MockChangeNotifier is a mock of ChangeNotifier interface

internal/store/mocks/utils_mocks.go

@@ -58,6 +58,20 @@ func (mr *MockListenerMockRecorder) Emit(arg0, arg1 interface{}) *gomock.Call {
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Emit", reflect.TypeOf((*MockListener)(nil).Emit), arg0, arg1)
 }
 
+// ProvideChannel mocks base method
+func (m *MockListener) ProvideChannel(arg0 string) <-chan string {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "ProvideChannel", arg0)
+	ret0, _ := ret[0].(<-chan string)
+	return ret0
+}
+
+// ProvideChannel indicates an expected call of ProvideChannel
+func (mr *MockListenerMockRecorder) ProvideChannel(arg0 interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "ProvideChannel", reflect.TypeOf((*MockListener)(nil).ProvideChannel), arg0)
+}
+
 // Remove mocks base method
 func (m *MockListener) Remove(arg0 string, arg1 chan<- string) {
 	m.ctrl.T.Helper()

internal/store/store.go

@@ -19,6 +19,7 @@
 package store
 
 import (
+	"context"
 	"fmt"
 	"os"
 	"sync"
@@ -34,15 +35,15 @@ import (
 )
 
 const (
-	// PathDelimiter for IMAP
+	// PathDelimiter for IMAP.
 	PathDelimiter = "/"
-	// UserLabelsMailboxName for IMAP
+	// UserLabelsMailboxName for IMAP.
 	UserLabelsMailboxName = "Labels"
-	// UserLabelsPrefix contains name with delimiter for IMAP
+	// UserLabelsPrefix contains name with delimiter for IMAP.
 	UserLabelsPrefix = UserLabelsMailboxName + PathDelimiter
-	// UserFoldersMailboxName for IMAP
+	// UserFoldersMailboxName for IMAP.
 	UserFoldersMailboxName = "Folders"
-	// UserFoldersPrefix contains name with delimiter for IMAP
+	// UserFoldersPrefix contains name with delimiter for IMAP.
 	UserFoldersPrefix = UserFoldersMailboxName + PathDelimiter
 )
 
@@ -51,9 +52,13 @@ var (
 
 	// Database structure:
 	// * metadata
-	//   * {messageID} -> message data (subject, from, to, time, headers, body size, ...)
+	//   * {messageID} -> message data (subject, from, to, time, body size, ...)
+	// * headers
+	//   * {messageID} -> header bytes
 	// * bodystructure
 	//   * {messageID} -> message body structure
+	// * msgbuildcount
+	//   * {messageID} -> uint32 number of message builds to track re-sync issues
 	// * counts
 	//   * {mailboxID} -> mailboxCounts: totalOnAPI, unreadOnAPI, labelName, labelColor, labelIsExclusive
 	// * address_info
@@ -75,7 +80,9 @@ var (
 	//     * deleted_ids (can be missing or have no keys)
 	//       * {messageID} -> true
 	metadataBucket      = []byte("metadata")          //nolint[gochecknoglobals]
+	headersBucket       = []byte("headers")           //nolint[gochecknoglobals]
 	bodystructureBucket = []byte("bodystructure")     //nolint[gochecknoglobals]
+	msgBuildCountBucket = []byte("msgbuildcount")     //nolint[gochecknoglobals]
 	countsBucket        = []byte("counts")            //nolint[gochecknoglobals]
 	addressInfoBucket   = []byte("address_info")      //nolint[gochecknoglobals]
 	addressModeBucket   = []byte("address_mode")      //nolint[gochecknoglobals]
@@ -94,13 +101,24 @@ var (
 	ErrNoSuchSeqNum = errors.New("no such sequence number") //nolint[gochecknoglobals]
 )
 
+// exposeContextForIMAP should be replaced once with context passed
+// as an argument from IMAP package and IMAP library should cancel
+// context when IMAP client cancels the request.
+func exposeContextForIMAP() context.Context {
+	return context.TODO()
+}
+
+// exposeContextForSMTP is the same as above but for SMTP.
+func exposeContextForSMTP() context.Context {
+	return context.TODO()
+}
+
 // Store is local user storage, which handles the synchronization between IMAP and PM API.
 type Store struct {
 	sentryReporter *sentry.Reporter
 	panicHandler   PanicHandler
 	eventLoop      *eventLoop
 	user           BridgeUser
-	clientManager  ClientManager
 
 	log *logrus.Entry
 
@@ -121,13 +139,12 @@ func New( // nolint[funlen]
 	sentryReporter *sentry.Reporter,
 	panicHandler PanicHandler,
 	user BridgeUser,
-	clientManager ClientManager,
 	events listener.Listener,
 	path string,
 	cache *Cache,
 ) (store *Store, err error) {
-	if user == nil || clientManager == nil || events == nil || cache == nil {
+	if user == nil || events == nil || cache == nil {
-		return nil, fmt.Errorf("missing parameters - user: %v, api: %v, events: %v, cache: %v", user, clientManager, events, cache)
+		return nil, fmt.Errorf("missing parameters - user: %v, events: %v, cache: %v", user, events, cache)
 	}
 
 	l := log.WithField("user", user.ID())
@@ -150,7 +167,6 @@ func New( // nolint[funlen]
 	store = &Store{
 		sentryReporter: sentryReporter,
 		panicHandler:   panicHandler,
-		clientManager:  clientManager,
 		user:           user,
 		cache:          cache,
 		filePath:       path,
@@ -196,36 +212,24 @@ func openBoltDatabase(filePath string) (db *bolt.DB, err error) {
 	}
 
 	tx := func(tx *bolt.Tx) (err error) {
-		if _, err = tx.CreateBucketIfNotExists(metadataBucket); err != nil {
+		buckets := [][]byte{
-			return
+			metadataBucket,
+			headersBucket,
+			bodystructureBucket,
+			msgBuildCountBucket,
+			countsBucket,
+			addressInfoBucket,
+			addressModeBucket,
+			syncStateBucket,
+			mailboxesBucket,
+			mboxVersionBucket,
 		}
 
-		if _, err = tx.CreateBucketIfNotExists(bodystructureBucket); err != nil {
+		for _, bucket := range buckets {
-			return
+			if _, err = tx.CreateBucketIfNotExists(bucket); err != nil {
-		}
+				err = errors.Wrap(err, string(bucket))
-
+				return
-		if _, err = tx.CreateBucketIfNotExists(countsBucket); err != nil {
+			}
-			return
-		}
-
-		if _, err = tx.CreateBucketIfNotExists(addressInfoBucket); err != nil {
-			return
-		}
-
-		if _, err = tx.CreateBucketIfNotExists(addressModeBucket); err != nil {
-			return
-		}
-
-		if _, err = tx.CreateBucketIfNotExists(syncStateBucket); err != nil {
-			return
-		}
-
-		if _, err = tx.CreateBucketIfNotExists(mailboxesBucket); err != nil {
-			return
-		}
-
-		if _, err = tx.CreateBucketIfNotExists(mboxVersionBucket); err != nil {
-			return
 		}
 
 		return
@@ -263,7 +267,7 @@ func (store *Store) init(firstInit bool) (err error) {
 		}
 	}
 
-	store.log.WithField("mode", store.addressMode).Debug("Initialising store")
+	store.log.WithField("mode", store.addressMode).Info("Initialising store")
 
 	labels, err := store.initCounts()
 	if err != nil {
@@ -280,13 +284,13 @@ func (store *Store) init(firstInit bool) (err error) {
 }
 
 func (store *Store) client() pmapi.Client {
-	return store.clientManager.GetClient(store.UserID())
+	return store.user.GetClient()
 }
 
 // initCounts initialises the counts for each label. It tries to use the API first to fetch the labels but if
 // the API is unavailable for whatever reason it tries to fetch the labels locally.
 func (store *Store) initCounts() (labels []*pmapi.Label, err error) {
-	if labels, err = store.client().ListLabels(); err != nil {
+	if labels, err = store.client().ListLabels(context.Background()); err != nil {
 		store.log.WithError(err).Warn("Could not list API labels. Trying with local labels.")
 		if labels, err = store.getLabelsFromLocalStorage(); err != nil {
 			store.log.WithError(err).Error("Cannot list local labels")

internal/store/store_test.go

@@ -18,6 +18,7 @@
 package store
 
 import (
+	"context"
 	"fmt"
 	"io/ioutil"
 	"os"
@@ -25,6 +26,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/ProtonMail/gopenpgp/v2/crypto"
 	storemocks "github.com/ProtonMail/proton-bridge/internal/store/mocks"
 	"github.com/ProtonMail/proton-bridge/pkg/pmapi"
 	pmapimocks "github.com/ProtonMail/proton-bridge/pkg/pmapi/mocks"
@@ -39,8 +41,92 @@ const (
 
 	addr2   = "jamesandmichalarecool@pm.me"
 	addrID2 = "jamesandmichalarecool"
+
+	testPrivateKeyPassword = "apple"
+	testPrivateKey         = `-----BEGIN PGP PRIVATE KEY BLOCK-----
+Version: OpenPGP.js v0.7.1
+Comment: http://openpgpjs.org
+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+=2wIY
+-----END PGP PRIVATE KEY BLOCK-----
+`
 )
 
+var testPrivateKeyRing *crypto.KeyRing
+
+func init() {
+	privKey, err := crypto.NewKeyFromArmored(testPrivateKey)
+	if err != nil {
+		panic(err)
+	}
+
+	privKeyUnlocked, err := privKey.Unlock([]byte(testPrivateKeyPassword))
+	if err != nil {
+		panic(err)
+	}
+
+	if testPrivateKeyRing, err = crypto.NewKeyRing(privKeyUnlocked); err != nil {
+		panic(err)
+	}
+}
+
 type mocksForStore struct {
 	tb testing.TB
 
@@ -48,7 +134,6 @@ type mocksForStore struct {
 	events         *storemocks.MockListener
 	user           *storemocks.MockBridgeUser
 	client         *pmapimocks.MockClient
-	clientManager  *storemocks.MockClientManager
 	panicHandler   *storemocks.MockPanicHandler
 	changeNotifier *storemocks.MockChangeNotifier
 	store          *Store
@@ -65,7 +150,6 @@ func initMocks(tb testing.TB) (*mocksForStore, func()) {
 		events:         storemocks.NewMockListener(ctrl),
 		user:           storemocks.NewMockBridgeUser(ctrl),
 		client:         pmapimocks.NewMockClient(ctrl),
-		clientManager:  storemocks.NewMockClientManager(ctrl),
 		panicHandler:   storemocks.NewMockPanicHandler(ctrl),
 		changeNotifier: storemocks.NewMockChangeNotifier(ctrl),
 	}
@@ -97,30 +181,30 @@ func (mocks *mocksForStore) newStoreNoEvents(combinedMode bool, msgs ...*pmapi.M
 	mocks.user.EXPECT().IsConnected().Return(true)
 	mocks.user.EXPECT().IsCombinedAddressMode().Return(combinedMode)
 
-	mocks.clientManager.EXPECT().GetClient("userID").AnyTimes().Return(mocks.client)
+	mocks.user.EXPECT().GetClient().AnyTimes().Return(mocks.client)
 
 	mocks.client.EXPECT().Addresses().Return(pmapi.AddressList{
-		{ID: addrID1, Email: addr1, Type: pmapi.OriginalAddress, Receive: pmapi.CanReceive},
+		{ID: addrID1, Email: addr1, Type: pmapi.OriginalAddress, Receive: true},
-		{ID: addrID2, Email: addr2, Type: pmapi.AliasAddress, Receive: pmapi.CanReceive},
+		{ID: addrID2, Email: addr2, Type: pmapi.AliasAddress, Receive: true},
 	})
-	mocks.client.EXPECT().ListLabels().AnyTimes()
+	mocks.client.EXPECT().ListLabels(gomock.Any()).AnyTimes()
-	mocks.client.EXPECT().CountMessages("")
+	mocks.client.EXPECT().CountMessages(gomock.Any(), "")
 
 	// Call to get latest event ID and then to process first event.
 	eventAfterSyncRequested := make(chan struct{})
-	mocks.client.EXPECT().GetEvent("").Return(&pmapi.Event{
+	mocks.client.EXPECT().GetEvent(gomock.Any(), "").Return(&pmapi.Event{
 		EventID: "firstEventID",
 	}, nil)
-	mocks.client.EXPECT().GetEvent("firstEventID").DoAndReturn(func(_ string) (*pmapi.Event, error) {
+	mocks.client.EXPECT().GetEvent(gomock.Any(), "firstEventID").DoAndReturn(func(_ context.Context, _ string) (*pmapi.Event, error) {
 		close(eventAfterSyncRequested)
 		return &pmapi.Event{
 			EventID: "latestEventID",
 		}, nil
 	})
 
-	mocks.client.EXPECT().ListMessages(gomock.Any()).Return(msgs, len(msgs), nil).AnyTimes()
+	mocks.client.EXPECT().ListMessages(gomock.Any(), gomock.Any()).Return(msgs, len(msgs), nil).AnyTimes()
 	for _, msg := range msgs {
-		mocks.client.EXPECT().GetMessage(msg.ID).Return(msg, nil).AnyTimes()
+		mocks.client.EXPECT().GetMessage(gomock.Any(), msg.ID).Return(msg, nil).AnyTimes()
 	}
 
 	var err error
@@ -128,7 +212,6 @@ func (mocks *mocksForStore) newStoreNoEvents(combinedMode bool, msgs ...*pmapi.M
 		nil, // Sentry reporter is not used under unit tests.
 		mocks.panicHandler,
 		mocks.user,
-		mocks.clientManager,
 		mocks.events,
 		filepath.Join(mocks.tmpDir, "mailbox-test.db"),
 		mocks.cache,

internal/store/store_test_exports.go

@@ -90,10 +90,7 @@ func (store *Store) TestDumpDB(tb assert.TestingT) {
 				return err
 			}
 		}
-		if err := txMails(tx); err != nil {
+		return txMails(tx)
-			return err
-		}
-		return nil
 	}
 
 	assert.NoError(tb, store.db.View(txDump))

internal/store/sync.go

@@ -18,6 +18,7 @@
 package store
 
 import (
+	"context"
 	"math"
 	"sync"
 
@@ -39,10 +40,10 @@ type storeSynchronizer interface {
 }
 
 type messageLister interface {
-	ListMessages(*pmapi.MessagesFilter) ([]*pmapi.Message, int, error)
+	ListMessages(context.Context, *pmapi.MessagesFilter) ([]*pmapi.Message, int, error)
 }
 
-func syncAllMail(panicHandler PanicHandler, store storeSynchronizer, api func() messageLister, syncState *syncState) error {
+func syncAllMail(panicHandler PanicHandler, store storeSynchronizer, api messageLister, syncState *syncState) error {
 	labelID := pmapi.AllMailLabel
 
 	// When the full sync starts (i.e. is not already in progress), we need to load
@@ -53,7 +54,7 @@ func syncAllMail(panicHandler PanicHandler, store storeSynchronizer, api func()
 			return errors.Wrap(err, "failed to load message IDs")
 		}
 
-		if err := findIDRanges(labelID, api(), syncState); err != nil {
+		if err := findIDRanges(labelID, api, syncState); err != nil {
 			return errors.Wrap(err, "failed to load IDs ranges")
 		}
 		syncState.save()
@@ -71,7 +72,7 @@ func syncAllMail(panicHandler PanicHandler, store storeSynchronizer, api func()
 			defer panicHandler.HandlePanic()
 			defer wg.Done()
 
-			err := syncBatch(labelID, store, api(), syncState, idRange, &shouldStop)
+			err := syncBatch(labelID, store, api, syncState, idRange, &shouldStop)
 			if err != nil {
 				shouldStop = 1
 				resultError = errors.Wrap(err, "failed to sync group")
@@ -147,7 +148,7 @@ func getSplitIDAndCount(labelID string, api messageLister, page int) (string, in
 		Limit:    1,
 	}
 	// If the page does not exist, an empty page instead of an error is returned.
-	messages, total, err := api.ListMessages(filter)
+	messages, total, err := api.ListMessages(context.Background(), filter)
 	if err != nil {
 		return "", 0, errors.Wrap(err, "failed to list messages")
 	}
@@ -189,7 +190,7 @@ func syncBatch( //nolint[funlen]
 
 		log.WithField("begin", filter.BeginID).WithField("end", filter.EndID).Debug("Fetching page")
 
-		messages, _, err := api.ListMessages(filter)
+		messages, _, err := api.ListMessages(context.Background(), filter)
 		if err != nil {
 			return errors.Wrap(err, "failed to list messages")
 		}

internal/store/sync_test.go

@@ -18,6 +18,7 @@
 package store
 
 import (
+	"context"
 	"sort"
 	"strconv"
 	"sync"
@@ -34,7 +35,7 @@ type mockLister struct {
 	messageIDs []string
 }
 
-func (m *mockLister) ListMessages(filter *pmapi.MessagesFilter) (msgs []*pmapi.Message, total int, err error) {
+func (m *mockLister) ListMessages(_ context.Context, filter *pmapi.MessagesFilter) (msgs []*pmapi.Message, total int, err error) {
 	if m.err != nil {
 		return nil, 0, m.err
 	}
@@ -197,7 +198,7 @@ func TestSyncAllMail(t *testing.T) { //nolint[funlen]
 
 			syncState := newSyncState(store, 0, tc.idRanges, tc.idsToBeDeleted)
 
-			err := syncAllMail(m.panicHandler, store, func() messageLister { return api }, syncState)
+			err := syncAllMail(m.panicHandler, store, api, syncState)
 			require.Nil(t, err)
 
 			// Check all messages were created or updated.
@@ -245,7 +246,7 @@ func TestSyncAllMail_FailedListing(t *testing.T) {
 	}
 	syncState := newTestSyncState(store)
 
-	err := syncAllMail(m.panicHandler, store, func() messageLister { return api }, syncState)
+	err := syncAllMail(m.panicHandler, store, api, syncState)
 	require.EqualError(t, err, "failed to sync group: failed to list messages: error")
 }
 
@@ -264,7 +265,7 @@ func TestSyncAllMail_FailedCreateOrUpdateMessage(t *testing.T) {
 	}
 	syncState := newTestSyncState(store)
 
-	err := syncAllMail(m.panicHandler, store, func() messageLister { return api }, syncState)
+	err := syncAllMail(m.panicHandler, store, api, syncState)
 	require.EqualError(t, err, "failed to sync group: failed to create or update messages: error")
 }
 

internal/store/types.go

@@ -17,16 +17,16 @@
 
 package store
 
-import "github.com/ProtonMail/proton-bridge/pkg/pmapi"
+import (
+	"context"
+
+	"github.com/ProtonMail/proton-bridge/pkg/pmapi"
+)
 
 type PanicHandler interface {
 	HandlePanic()
 }
 
-type ClientManager interface {
-	GetClient(userID string) pmapi.Client
-}
-
 // BridgeUser is subset of bridge.User for use by the Store.
 type BridgeUser interface {
 	ID() string
@@ -35,7 +35,8 @@ type BridgeUser interface {
 	IsCombinedAddressMode() bool
 	GetPrimaryAddress() string
 	GetStoreAddresses() []string
-	UpdateUser() error
+	GetClient() pmapi.Client
+	UpdateUser(context.Context) error
 	CloseAllConnections()
 	CloseConnection(string)
 	Logout() error

internal/store/user.go

@@ -24,7 +24,7 @@ func (store *Store) UserID() string {
 
 // GetSpace returns used and total space in bytes.
 func (store *Store) GetSpace() (usedSpace, maxSpace uint, err error) {
-	apiUser, err := store.client().CurrentUser()
+	apiUser, err := store.client().CurrentUser(exposeContextForIMAP())
 	if err != nil {
 		return 0, 0, err
 	}
@@ -33,7 +33,7 @@ func (store *Store) GetSpace() (usedSpace, maxSpace uint, err error) {
 
 // GetMaxUpload returns max size of message + all attachments in bytes.
 func (store *Store) GetMaxUpload() (int64, error) {
-	apiUser, err := store.client().CurrentUser()
+	apiUser, err := store.client().CurrentUser(exposeContextForIMAP())
 	if err != nil {
 		return 0, err
 	}

internal/store/user_address_info.go

@@ -147,7 +147,7 @@ func (store *Store) createOrUpdateAddressInfo(addressList pmapi.AddressList) (er
 // filterAddresses filters out inactive addresses and ensures the original address is listed first.
 func filterAddresses(addressList pmapi.AddressList) (filteredList pmapi.AddressList) {
 	for _, address := range addressList {
-		if address.Receive != pmapi.CanReceive {
+		if !address.Receive {
 			continue
 		}