chore: Bridge Perth Narrows 3.0.18

fix(GODT-2399): Defer updated message deletion
fix(GODT-2400): Allow state updates to be applied if command fails
fix(GODT-2414): Multiple deletion bug in WriteControlledStore

Changelog.md

@@ -2,6 +2,21 @@
 
 Changelog [format](http://keepachangelog.com/en/1.0.0/)
 
+## [Bridge 3.0.18] Perth Narrows
+
+### Fixed
+* GODT-2364: Wait and retry once if the gRPC service config file exists but cannot be opened.
+* GODT-2364: Added optional details to C++ exceptions.
+* GODT-2413: Use qEnvironmentVariable() instead of qgetenv().
+* GODT-2412: Don't treat context cancellation as BadEvent.
+* GODT-2404: Handle unexpected EOF.
+* GODT-2400: Allow state updates to be applied if command fails.
+* GODT-2399: Fix immediate message deletion during updates.
+* GODT-2390: Missing changes from pervious commit.
+* GODT-2390: Add reports for uncaught json and net.opErr.
+* GODT-2414: Multiple deletion bug in WriteControlledStore.
+
+
 ## [Bridge 3.0.18] Perth Narrows
 
 ### Fixed

Makefile

@@ -11,7 +11,7 @@ ROOT_DIR:=$(shell dirname $(realpath $(firstword $(MAKEFILE_LIST))))
 .PHONY: build build-gui build-nogui build-launcher versioner hasher
 
 # Keep version hardcoded so app build works also without Git repository.
-BRIDGE_APP_VERSION?=3.0.18+git
+BRIDGE_APP_VERSION?=3.0.19+git
 APP_VERSION:=${BRIDGE_APP_VERSION}
 APP_FULL_NAME:=Proton Mail Bridge
 APP_VENDOR:=Proton AG

go.mod

@@ -5,7 +5,7 @@ go 1.18
 require (
 	github.com/0xAX/notificator v0.0.0-20220220101646-ee9b8921e557
 	github.com/Masterminds/semver/v3 v3.1.1
-	github.com/ProtonMail/gluon v0.14.2-0.20230221144759-b277a90ca303
+	github.com/ProtonMail/gluon v0.14.2-0.20230227135029-cef8f5824680
 	github.com/ProtonMail/go-autostart v0.0.0-20210130080809-00ed301c8e9a
 	github.com/ProtonMail/go-proton-api v0.3.1-0.20230209110241-fe7894c4931a
 	github.com/ProtonMail/go-rfc5322 v0.11.0

go.sum

@@ -28,8 +28,8 @@ github.com/ProtonMail/bcrypt v0.0.0-20211005172633-e235017c1baf h1:yc9daCCYUefEs
 github.com/ProtonMail/bcrypt v0.0.0-20211005172633-e235017c1baf/go.mod h1:o0ESU9p83twszAU8LBeJKFAAMX14tISa0yk4Oo5TOqo=
 github.com/ProtonMail/docker-credential-helpers v1.1.0 h1:+kvUIpwWcbtP3WFv5sSvkFn/XLzSqPOB5AAthuk9xPk=
 github.com/ProtonMail/docker-credential-helpers v1.1.0/go.mod h1:mK0aBveCxhnQ756AmaTfXMZDeULvheYVhF/MWMErN5g=
-github.com/ProtonMail/gluon v0.14.2-0.20230221144759-b277a90ca303 h1:OTzqa4dcVuo4O4Kkng8rcoKJiKEY9HalQb8Y3OJWNFA=
-github.com/ProtonMail/gluon v0.14.2-0.20230221144759-b277a90ca303/go.mod h1:z2AxLIiBCT1K+0OBHyaDI7AEaO5qI6/BEC2TE42vs4Q=
+github.com/ProtonMail/gluon v0.14.2-0.20230227135029-cef8f5824680 h1:NGp7LfbsKePRHBgMcgquycHx3CSuS7255i0wanAiCuY=
+github.com/ProtonMail/gluon v0.14.2-0.20230227135029-cef8f5824680/go.mod h1:z2AxLIiBCT1K+0OBHyaDI7AEaO5qI6/BEC2TE42vs4Q=
 github.com/ProtonMail/go-autostart v0.0.0-20210130080809-00ed301c8e9a h1:D+aZah+k14Gn6kmL7eKxoo/4Dr/lK3ChBcwce2+SQP4=
 github.com/ProtonMail/go-autostart v0.0.0-20210130080809-00ed301c8e9a/go.mod h1:oTGdE7/DlWIr23G0IKW3OXK9wZ5Hw1GGiaJFccTvZi4=
 github.com/ProtonMail/go-crypto v0.0.0-20210428141323-04723f9f07d7/go.mod h1:z4/9nQmJSSwwds7ejkxaJwO37dru3geImFUdJlaLzQo=

internal/bridge/user_events.go

@@ -22,6 +22,7 @@ import (
 	"fmt"
 
 	"github.com/ProtonMail/gluon/reporter"
+	"github.com/ProtonMail/proton-bridge/v3/internal"
 	"github.com/ProtonMail/proton-bridge/v3/internal/events"
 	"github.com/ProtonMail/proton-bridge/v3/internal/safe"
 	"github.com/ProtonMail/proton-bridge/v3/internal/user"
@@ -56,6 +57,9 @@ func (bridge *Bridge) handleUserEvent(ctx context.Context, user *user.User, even
 
 	case events.UserBadEvent:
 		bridge.handleUserBadEvent(ctx, user, event.Error)
+
+	case events.UncategorizedEventError:
+		bridge.handleUncategorizedErrorEvent(event)
 	}
 
 	return nil
@@ -139,7 +143,8 @@ func (bridge *Bridge) handleUserDeauth(ctx context.Context, user *user.User) {
 func (bridge *Bridge) handleUserBadEvent(ctx context.Context, user *user.User, err error) {
 	safe.Lock(func() {
 		if rerr := bridge.reporter.ReportMessageWithContext("Failed to handle event", reporter.Context{
-			"error": err,
+			"error_type": fmt.Sprintf("%T", internal.ErrCause(err)),
+			"error":      err,
 		}); rerr != nil {
 			logrus.WithError(rerr).Error("Failed to report failed event handling")
 		}
@@ -147,3 +152,12 @@ func (bridge *Bridge) handleUserBadEvent(ctx context.Context, user *user.User, e
 		bridge.logoutUser(ctx, user, true, false)
 	}, bridge.usersLock)
 }
+
+func (bridge *Bridge) handleUncategorizedErrorEvent(event events.UncategorizedEventError) {
+	if rerr := bridge.reporter.ReportMessageWithContext("Failed to handle due to uncategorized error", reporter.Context{
+		"error_type": fmt.Sprintf("%T", internal.ErrCause(event.Error)),
+		"error":      event.Error,
+	}); rerr != nil {
+		logrus.WithError(rerr).Error("Failed to report failed event handling")
+	}
+}

internal/errors.go

@@ -0,0 +1,31 @@
+// Copyright (c) 2023 Proton AG
+//
+// This file is part of Proton Mail Bridge.
+//
+// Proton Mail 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.
+//
+// Proton Mail 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 Proton Mail Bridge. If not, see <https://www.gnu.org/licenses/>.
+
+package internal
+
+import "errors"
+
+// ErrCause returns the cause of the error, the inner-most error in the wrapped chain.
+func ErrCause(err error) error {
+	cause := err
+
+	for errors.Unwrap(cause) != nil {
+		cause = errors.Unwrap(cause)
+	}
+
+	return cause
+}

internal/events/user.go

@@ -156,3 +156,14 @@ type AddressModeChanged struct {
 func (event AddressModeChanged) String() string {
 	return fmt.Sprintf("AddressModeChanged: UserID: %s, AddressMode: %s", event.UserID, event.AddressMode)
 }
+
+type UncategorizedEventError struct {
+	eventBase
+
+	UserID string
+	Error  error
+}
+
+func (event UncategorizedEventError) String() string {
+	return fmt.Sprintf("UncategorizedEventError: UserID: %s, Source:%T, Error: %s", event.UserID, event.Error, event.Error)
+}

internal/frontend/bridge-gui/bridge-gui/AppController.cpp

@@ -73,13 +73,17 @@ ProcessMonitor *AppController::bridgeMonitor() const {
 //****************************************************************************************************************************************************
 /// \param[in] function The function that caught the exception.
 /// \param[in] message The error message.
+/// \param[in] details The details for the error.
 //****************************************************************************************************************************************************
-void AppController::onFatalError(QString const &function, QString const &message) {
-    QString const fullMessage = QString("%1(): %2").arg(function, message);
-    auto uuid = reportSentryException(SENTRY_LEVEL_ERROR, "AppController got notified of a fatal error", "Exception", fullMessage.toLocal8Bit());
+void AppController::onFatalError(QString const &function, QString const &message, QString const& details) {
+    QString fullMessage = QString("%1(): %2").arg(function, message);
+    if (!details.isEmpty())
+        fullMessage += "\n\nDetails:\n" + details;
+    sentry_uuid_s const uuid = reportSentryException(SENTRY_LEVEL_ERROR, "AppController got notified of a fatal error", "Exception",
+        fullMessage.toLocal8Bit());
     QMessageBox::critical(nullptr, tr("Error"), message);
     restart(true);
-    log().fatal(QString("reportID: %1 Captured exception: %2").arg(QByteArray(uuid.bytes, 16).toHex()).arg(fullMessage));
+    log().fatal(QString("reportID: %1 Captured exception: %2").arg(QByteArray(uuid.bytes, 16).toHex(), fullMessage));
     qApp->exit(EXIT_FAILURE);
 }
 

internal/frontend/bridge-gui/bridge-gui/AppController.h

@@ -58,7 +58,7 @@ public: // member functions.
     void setLauncherArgs(const QString& launcher, const QStringList& args);
 
 public slots:
-    void onFatalError(QString const &function, QString const &message); ///< Handle fatal errors.
+    void onFatalError(QString const &function, QString const &message, QString const& details); ///< Handle fatal errors.
 
 private: // member functions
     AppController(); ///< Default constructor.

internal/frontend/bridge-gui/bridge-gui/QMLBackend.cpp

@@ -25,8 +25,8 @@
 
 
 #define HANDLE_EXCEPTION(x) try { x } \
-    catch (Exception const &e) { emit fatalError(__func__, e.qwhat()); } \
-    catch (...)  { emit fatalError(__func__, QString("An unknown exception occurred")); }
+    catch (Exception const &e) { emit fatalError(__func__, e.qwhat(), e.details()); } \
+    catch (...)  { emit fatalError(__func__, QString("An unknown exception occurred"), QString()); }
 #define HANDLE_EXCEPTION_RETURN_BOOL(x) HANDLE_EXCEPTION(x) return false;
 #define HANDLE_EXCEPTION_RETURN_QSTRING(x) HANDLE_EXCEPTION(x) return QString();
 #define HANDLE_EXCEPTION_RETURN_ZERO(x) HANDLE_EXCEPTION(x) return 0;
@@ -56,12 +56,8 @@ void QMLBackend::init(GRPCConfig const &serviceConfig) {
     app().grpc().setLog(&log);
     this->connectGrpcEvents();
 
-    QString error;
-    if (app().grpc().connectToServer(serviceConfig, app().bridgeMonitor(), error)) {
-        app().log().info("Connected to backend via gRPC service.");
-    } else {
-        throw Exception(QString("Cannot connectToServer to go backend via gRPC: %1").arg(error));
-    }
+    app().grpc().connectToServer(serviceConfig, app().bridgeMonitor());
+    app().log().info("Connected to backend via gRPC service.");
 
     QString bridgeVer;
     app().grpc().version(bridgeVer);
@@ -597,7 +593,8 @@ void QMLBackend::setDiskCachePath(QUrl const &path) const {
 void QMLBackend::login(QString const &username, QString const &password) const {
     HANDLE_EXCEPTION(
         if (username.compare("coco@bandicoot", Qt::CaseInsensitive) == 0) {
-            throw Exception("User requested bridge-gui to crash by trying to log as coco@bandicoot");
+            throw Exception("User requested bridge-gui to crash by trying to log as coco@bandicoot",
+                "This error exists for test purposes and should be ignored.");
         }
         app().grpc().login(username, password);
     )

internal/frontend/bridge-gui/bridge-gui/QMLBackend.h

@@ -235,7 +235,7 @@ signals: // Signals received from the Go backend, to be forwarded to QML
     void selectUser(QString const); ///< Signal that request the given user account to be displayed.
 
     // This signal is emitted when an exception is intercepted is calls triggered by QML. QML engine would intercept the exception otherwise.
-    void fatalError(QString const &function, QString const &message) const; ///< Signal emitted when an fatal error occurs.
+    void fatalError(QString const &function, QString const &message, QString const &details) const; ///< Signal emitted when an fatal error occurs.
 
 private: // member functions
     void retrieveUserList(); ///< Retrieve the list of users via gRPC.

internal/frontend/bridge-gui/bridge-gui/main.cpp

@@ -428,9 +428,16 @@ int main(int argc, char *argv[]) {
         return result;
     }
     catch (Exception const &e) {
-        auto uuid = reportSentryException(SENTRY_LEVEL_ERROR, "Exception occurred during main", "Exception", e.what());
+        QString fullMessage = e.qwhat();
+        bool const hasDetails = !e.details().isEmpty();
+        if (hasDetails)
+            fullMessage += "\n\nDetails:\n" + e.details();
+        sentry_uuid_s const uuid = reportSentryException(SENTRY_LEVEL_ERROR, "Exception occurred during main", "Exception", fullMessage.toLocal8Bit());
         QMessageBox::critical(nullptr, "Error", e.qwhat());
-        QTextStream(stderr) << "reportID: " << QByteArray(uuid.bytes, 16).toHex() << "Captured exception :" << e.qwhat() << "\n";
+        QTextStream errStream(stderr);
+        errStream << "reportID: " << QByteArray(uuid.bytes, 16).toHex() << " Captured exception :" << e.qwhat() << "\n";
+        if (hasDetails)
+            errStream << "\nDetails:\n" << e.details() << "\n";
         return EXIT_FAILURE;
     }
 }

internal/frontend/bridge-gui/bridgepp/bridgepp/BridgeUtils.cpp

@@ -71,20 +71,20 @@ std::mt19937_64 &rng() {
 QString userConfigDir() {
     QString dir;
 #ifdef Q_OS_WIN
-    dir = qgetenv ("AppData");
+    dir = qEnvironmentVariable("AppData");
     if (dir.isEmpty())
         throw Exception("%AppData% is not defined.");
 #elif defined(Q_OS_IOS) || defined(Q_OS_DARWIN)
-    dir = qgetenv("HOME");
+    dir = qEnvironmentVariable("HOME");
     if (dir.isEmpty()) {
         throw Exception("$HOME is not defined.");
     }
     dir += "/Library/Application Support";
 #else
-    dir = qgetenv ("XDG_CONFIG_HOME");
+    dir = qEnvironmentVariable("XDG_CONFIG_HOME");
     if (dir.isEmpty())
     {
-        dir = qgetenv ("HOME");
+        dir = qEnvironmentVariable("HOME");
         if (dir.isEmpty())
             throw Exception("neither $XDG_CONFIG_HOME nor $HOME are defined");
         dir += "/.config";
@@ -104,20 +104,20 @@ QString userCacheDir() {
     QString dir;
 
 #ifdef Q_OS_WIN
-    dir = qgetenv ("LocalAppData");
+    dir = qEnvironmentVariable("LocalAppData");
     if (dir.isEmpty())
         throw Exception("%LocalAppData% is not defined.");
 #elif defined(Q_OS_IOS) || defined(Q_OS_DARWIN)
-    dir = qgetenv("HOME");
+    dir = qEnvironmentVariable("HOME");
     if (dir.isEmpty()) {
         throw Exception("$HOME is not defined.");
     }
     dir += "/Library/Caches";
 #else
-    dir = qgetenv ("XDG_CACHE_HOME");
+    dir = qEnvironmentVariable("XDG_CACHE_HOME");
     if (dir.isEmpty())
     {
-        dir = qgetenv ("HOME");
+        dir = qEnvironmentVariable("HOME");
         if (dir.isEmpty())
             throw Exception("neither $XDG_CACHE_HOME nor $HOME are defined");
         dir += "/.cache";
@@ -138,10 +138,10 @@ QString userDataDir() {
     QString folder;
 
 #ifdef Q_OS_LINUX
-    QString dir = qgetenv ("XDG_DATA_HOME");
+    QString dir = qEnvironmentVariable("XDG_DATA_HOME");
     if (dir.isEmpty())
     {
-        dir = qgetenv ("HOME");
+        dir = qEnvironmentVariable("HOME");
         if (dir.isEmpty())
             throw Exception("neither $XDG_DATA_HOME nor $HOME are defined");
         dir += "/.local/share";

internal/frontend/bridge-gui/bridgepp/bridgepp/Exception/Exception.cpp

@@ -23,11 +23,13 @@ namespace bridgepp {
 
 
 //****************************************************************************************************************************************************
-/// \param[in] what A description of the exception
+/// \param[in] what A description of the exception.
+/// \param[in] details The optional details for the exception.
 //****************************************************************************************************************************************************
-Exception::Exception(QString what) noexcept
+Exception::Exception(QString what, QString details) noexcept
     : std::exception()
-    , what_(std::move(what)) {
+    , what_(std::move(what))
+    , details_(std::move(details)) {
 }
 
 
@@ -36,7 +38,8 @@ Exception::Exception(QString what) noexcept
 //****************************************************************************************************************************************************
 Exception::Exception(Exception const &ref) noexcept
     : std::exception(ref)
-    , what_(ref.what_) {
+    , what_(ref.what_)
+    , details_(ref.details_) {
 }
 
 
@@ -45,14 +48,15 @@ Exception::Exception(Exception const &ref) noexcept
 //****************************************************************************************************************************************************
 Exception::Exception(Exception &&ref) noexcept
     : std::exception(ref)
-    , what_(ref.what_) {
+    , what_(ref.what_)
+    , details_(ref.details_) {
 }
 
 
 //****************************************************************************************************************************************************
 /// \return a string describing the exception
 //****************************************************************************************************************************************************
-QString const &Exception::qwhat() const noexcept {
+QString Exception::qwhat() const noexcept {
     return what_;
 }
 
@@ -65,4 +69,12 @@ const char *Exception::what() const noexcept {
 }
 
 
+//****************************************************************************************************************************************************
+/// \return The details for the exception.
+//****************************************************************************************************************************************************
+QString Exception::details() const noexcept {
+    return details_;
+}
+
+
 } // namespace bridgepp

internal/frontend/bridge-gui/bridgepp/bridgepp/Exception/Exception.h

@@ -31,17 +31,19 @@ namespace bridgepp {
 //****************************************************************************************************************************************************
 class Exception : public std::exception {
 public: // member functions
-    explicit Exception(QString what = QString()) noexcept; ///< Constructor
+    explicit Exception(QString what = QString(), QString details = QString()) noexcept; ///< Constructor
     Exception(Exception const &ref) noexcept; ///< copy constructor
     Exception(Exception &&ref) noexcept; ///< copy constructor
     Exception &operator=(Exception const &) = delete; ///< Disabled assignment operator
     Exception &operator=(Exception &&) = delete; ///< Disabled assignment operator
     ~Exception() noexcept override = default; ///< Destructor
-    QString const &qwhat() const noexcept; ///< Return the description of the exception as a QString
+    QString qwhat() const noexcept; ///< Return the description of the exception as a QString
     const char *what() const noexcept override; ///< Return the description of the exception as C style string
+    QString details() const noexcept; ///< Return the details for the exception
 
 private: // data members
-    QString const what_; ///< The description of the exception
+    QString const what_; ///< The description of the exception.
+    QString const details_; ///< The optional details for the exception.
 };
 
 

internal/frontend/bridge-gui/bridgepp/bridgepp/GRPC/GRPCClient.cpp

@@ -88,8 +88,9 @@ GRPCConfig GRPCClient::waitAndRetrieveServiceConfig(qint64 timeoutMs, ProcessMon
     }
 
     GRPCConfig sc;
-    if (!sc.load(path)) {
-        throw Exception("The gRPC service configuration file is invalid.");
+    QString err;
+    if (!sc.load(path, &err)) {
+        throw Exception("The gRPC service configuration file is invalid.", err);
     }
 
     return sc;
@@ -105,11 +106,10 @@ void GRPCClient::setLog(Log *log) {
 
 
 //****************************************************************************************************************************************************
-/// \param[out] outError If the function returns false, this variable contains a description of the error.
 /// \param[in] serverProcess An optional server process to monitor. If the process it, no need and retry, as connexion cannot be established. Ignored if null.
 /// \return true iff the connection was successful.
 //****************************************************************************************************************************************************
-bool GRPCClient::connectToServer(GRPCConfig const &config, ProcessMonitor *serverProcess, QString &outError) {
+void GRPCClient::connectToServer(GRPCConfig const &config, ProcessMonitor *serverProcess) {
     try {
         serverToken_ = config.token.toStdString();
         QString address;
@@ -158,9 +158,10 @@ bool GRPCClient::connectToServer(GRPCConfig const &config, ProcessMonitor *serve
         this->logInfo("Successfully connected to gRPC server.");
 
         QString const clientToken = QUuid::createUuid().toString();
-        QString clientConfigPath = createClientConfigFile(clientToken);
+        QString error;
+        QString clientConfigPath = createClientConfigFile(clientToken, &error);
         if (clientConfigPath.isEmpty()) {
-            throw Exception("gRPC client config could not be saved.");
+            throw Exception("gRPC client config could not be saved.", error);
         }
         this->logInfo(QString("Client config file was saved to '%1'").arg(QDir::toNativeSeparators(clientConfigPath)));
 
@@ -176,12 +177,9 @@ bool GRPCClient::connectToServer(GRPCConfig const &config, ProcessMonitor *serve
         }
 
         log_->info("gRPC token was validated");
-
-        return true;
     }
     catch (Exception const &e) {
-        outError = e.qwhat();
-        return false;
+        throw Exception("Cannot connect to Go backend via gRPC: " + e.qwhat(), e.details());
     }
 }
 

internal/frontend/bridge-gui/bridgepp/bridgepp/GRPC/GRPCClient.h

@@ -59,7 +59,7 @@ public: // member functions.
     GRPCClient &operator=(GRPCClient const &) = delete; ///< Disabled assignment operator.
     GRPCClient &operator=(GRPCClient &&) = delete; ///< Disabled move assignment operator.
     void setLog(Log *log); ///< Set the log for the client.
-    bool connectToServer(GRPCConfig const &config, class ProcessMonitor *serverProcess, QString &outError); ///< Establish connection to the gRPC server.
+    void connectToServer(GRPCConfig const &config, class ProcessMonitor *serverProcess); ///< Establish connection to the gRPC server.
 
     grpc::Status checkTokens(QString const &clientConfigPath, QString &outReturnedClientToken); ///< Performs a token check.
     grpc::Status addLogEntry(Log::Level level, QString const &package, QString const &message); ///< Performs the "AddLogEntry" gRPC call.

internal/frontend/bridge-gui/bridgepp/bridgepp/GRPC/GRPCConfig.cpp

@@ -25,8 +25,7 @@ using namespace bridgepp;
 
 namespace {
 
-Exception const invalidFileException("The service configuration file is invalid"); // Exception for invalid config.
-Exception const couldNotSaveException("The service configuration file could not be saved"); ///< Exception for write errors.
+Exception const invalidFileException("The content of the service configuration file is invalid"); // Exception for invalid config.
 QString const keyPort = "port"; ///< The JSON key for the port.
 QString const keyCert = "cert"; ///< The JSON key for the TLS certificate.
 QString const keyToken = "token"; ///< The JSON key for the identification token.
@@ -78,8 +77,14 @@ qint32 jsonIntValue(QJsonObject const &object, QString const &key) {
 bool GRPCConfig::load(QString const &path, QString *outError) {
     try {
         QFile file(path);
+        if (!file.exists())
+            throw Exception("The gRPC service configuration file does not exist.");
+
         if (!file.open(QIODevice::ReadOnly | QIODevice::Text)) {
-            throw Exception("Could not open gRPC service config file.");
+            QThread::msleep(500); // we wait a bit and retry once, just in case server is not done writing/moving the config file.
+            if (!file.open(QIODevice::ReadOnly | QIODevice::Text)) {
+                throw Exception("The gRPC service configuration file exists but cannot be opened.");
+            }
         }
 
         QJsonDocument const doc = QJsonDocument::fromJson(file.readAll());
@@ -93,7 +98,7 @@ bool GRPCConfig::load(QString const &path, QString *outError) {
     }
     catch (Exception const &e) {
         if (outError) {
-            *outError = e.qwhat();
+            *outError = QString("Error loading gRPC service configuration file '%1'.\n%2").arg(QFileInfo(path).absoluteFilePath(), e.qwhat());
         }
         return false;
     }
@@ -115,19 +120,19 @@ bool GRPCConfig::save(QString const &path, QString *outError) {
 
         QFile file(path);
         if (!file.open(QIODevice::WriteOnly | QIODevice::Text)) {
-            throw couldNotSaveException;
+            throw Exception("The file could not be opened for writing.");
         }
 
         QByteArray const array = QJsonDocument(object).toJson();
         if (array.size() != file.write(array)) {
-            throw couldNotSaveException;
+            throw Exception("An error occurred while writing to the file.");
         }
 
         return true;
     }
     catch (Exception const &e) {
         if (outError) {
-            *outError = e.qwhat();
+            *outError = QString("Error saving gRPC service configuration file '%1'.\n%2").arg(QFileInfo(path).absoluteFilePath(), e.qwhat());
         }
         return false;
     }

internal/frontend/bridge-gui/bridgepp/bridgepp/GRPC/GRPCUtils.cpp

@@ -76,10 +76,12 @@ QString grpcClientConfigBasePath() {
 
 //****************************************************************************************************************************************************
 /// \param[in] token The token to put in the file.
+/// \param[out] outError if the function returns an empty string and this pointer is not null, the pointer variable holds a description of the error
+/// on exit.
 /// \return The path of the created file.
-/// \return A null string if the file could not be saved..
+/// \return A null string if the file could not be saved.
 //****************************************************************************************************************************************************
-QString createClientConfigFile(QString const &token) {
+QString createClientConfigFile(QString const &token, QString *outError) {
     QString const basePath = grpcClientConfigBasePath();
     QString path, error;
     for (qint32 i = 0; i < 1000; ++i) // we try a decent amount of times
@@ -88,13 +90,16 @@ QString createClientConfigFile(QString const &token) {
         if (!QFileInfo(path).exists()) {
             GRPCConfig config;
             config.token = token;
-            if (!config.save(path)) {
+
+            if (!config.save(path, outError)) {
                 return QString();
             }
             return path;
         }
     }
 
+    if (outError)
+        *outError = "no usable client configuration file name could be found.";
     return QString();
 }
 

internal/frontend/bridge-gui/bridgepp/bridgepp/GRPC/GRPCUtils.h

@@ -36,7 +36,7 @@ typedef std::shared_ptr<grpc::StreamEvent> SPStreamEvent; ///< Type definition f
 
 QString grpcServerConfigPath(); ///< Return the path of the gRPC server config file.
 QString grpcClientConfigBasePath(); ///< Return the path of the gRPC client config file.
-QString createClientConfigFile(QString const &token); ///< Create the client config file the server will retrieve and return its path.
+QString createClientConfigFile(QString const &token, QString *outError); ///< Create the client config file the server will retrieve and return its path.
 grpc::LogLevel logLevelToGRPC(Log::Level level); ///< Convert a Log::Level to gRPC enum value.
 Log::Level logLevelFromGRPC(grpc::LogLevel level); ///< Convert a grpc::LogLevel to a Log::Level.
 grpc::UserState userStateToGRPC(UserState state); ///< Convert a bridgepp::UserState to a grpc::UserState.

internal/user/user.go

@@ -20,10 +20,11 @@ package user
 import (
 	"context"
 	"crypto/subtle"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"io"
-	"net/url"
+	"net"
 	"strings"
 	"sync/atomic"
 	"time"
@@ -33,6 +34,7 @@ import (
 	"github.com/ProtonMail/gluon/queue"
 	"github.com/ProtonMail/gluon/reporter"
 	"github.com/ProtonMail/go-proton-api"
+	"github.com/ProtonMail/proton-bridge/v3/internal"
 	"github.com/ProtonMail/proton-bridge/v3/internal/async"
 	"github.com/ProtonMail/proton-bridge/v3/internal/events"
 	"github.com/ProtonMail/proton-bridge/v3/internal/logging"
@@ -626,7 +628,7 @@ func (user *User) doEventPoll(ctx context.Context) error {
 
 	event, err := user.client.GetEvent(ctx, user.vault.EventID())
 	if err != nil {
-		return fmt.Errorf("failed to get event: %w", err)
+		return fmt.Errorf("failed to get event (caused by %T): %w", internal.ErrCause(err), err)
 	}
 
 	// If the event ID hasn't changed, there are no new events.
@@ -642,14 +644,44 @@ func (user *User) doEventPoll(ctx context.Context) error {
 
 	// Handle the event.
 	if err := user.handleAPIEvent(ctx, event); err != nil {
+		// If the error is a context cancellation, return error to retry later.
+		if errors.Is(err, context.Canceled) {
+			return fmt.Errorf("failed to handle event due to context cancellation: %w", err)
+		}
+
 		// If the error is a network error, return error to retry later.
 		if netErr := new(proton.NetError); errors.As(err, &netErr) {
 			return fmt.Errorf("failed to handle event due to network issue: %w", err)
 		}
 
-		// If the error is a url.Error, return error to retry later.
-		if urlErr := new(url.Error); errors.As(err, &urlErr) {
-			return fmt.Errorf("failed to handle event due to URL issue: %w", err)
+		// Catch all for uncategorized net errors that may slip through.
+		if netErr := new(net.OpError); errors.As(err, &netErr) {
+			user.eventCh.Enqueue(events.UncategorizedEventError{
+				UserID: user.ID(),
+				Error:  err,
+			})
+
+			return fmt.Errorf("failed to handle event due to network issues (uncategorized): %w", err)
+		}
+
+		// In case a json decode error slips through.
+		if jsonErr := new(json.UnmarshalTypeError); errors.As(err, &jsonErr) {
+			user.eventCh.Enqueue(events.UncategorizedEventError{
+				UserID: user.ID(),
+				Error:  err,
+			})
+
+			return fmt.Errorf("failed to handle event due to JSON issue: %w", err)
+		}
+
+		// If the error is an unexpected EOF, return error to retry later.
+		if errors.Is(err, io.ErrUnexpectedEOF) {
+			user.eventCh.Enqueue(events.UncategorizedEventError{
+				UserID: user.ID(),
+				Error:  err,
+			})
+
+			return fmt.Errorf("failed to handle event due to EOF: %w", err)
 		}
 
 		// If the error is a server-side issue, return error to retry later.