We build too many walls and not enough bridges

pkg/updates/downloader.go

@@ -0,0 +1,131 @@
+// Copyright (c) 2020 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 updates
+
+import (
+	"errors"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"os"
+	"path/filepath"
+	"strconv"
+
+	"github.com/ProtonMail/proton-bridge/pkg/dialer"
+)
+
+func mkdirAllClear(path string) error {
+	if err := os.RemoveAll(path); err != nil {
+		return err
+	}
+	return os.MkdirAll(path, 0750)
+}
+
+func downloadToBytes(path string) (out []byte, err error) {
+	var (
+		client   *http.Client
+		response *http.Response
+	)
+	client = dialer.DialTimeoutClient()
+	log.WithField("path", path).Trace("Downloading")
+
+	response, err = client.Get(path)
+	if err != nil {
+		return
+	}
+	out, err = ioutil.ReadAll(response.Body)
+	_ = response.Body.Close()
+	if response.StatusCode < http.StatusOK || http.StatusIMUsed < response.StatusCode {
+		err = errors.New(path + " " + response.Status)
+	}
+	return
+}
+
+func downloadWithProgress(status *Progress, sourceURL, targetPath string) (err error) {
+	targetFile, err := os.Create(targetPath)
+	if err != nil {
+		log.Warnf("Cannot create update file %s: %v", targetPath, err)
+		return
+	}
+	defer targetFile.Close() //nolint[errcheck]
+
+	var (
+		client   *http.Client
+		response *http.Response
+	)
+	client = dialer.DialTimeoutClient()
+	response, err = client.Get(sourceURL)
+	if err != nil {
+		return
+	}
+	defer response.Body.Close() //nolint[errcheck]
+
+	contentLength, _ := strconv.ParseUint(response.Header.Get("Content-Length"), 10, 64)
+
+	wc := WriteCounter{
+		Status: status,
+		Target: targetFile,
+		Size:   contentLength,
+	}
+
+	err = wc.ReadAll(response.Body)
+	return
+}
+
+func downloadWithSignature(status *Progress, sourceURL, targetDir string) (localPath string, err error) {
+	localPath = filepath.Join(targetDir, filepath.Base(sourceURL))
+
+	if err = downloadWithProgress(nil, sourceURL+sigExtension, localPath+sigExtension); err != nil {
+		return
+	}
+
+	if err = downloadWithProgress(status, sourceURL, localPath); err != nil {
+		return
+	}
+	return
+}
+
+type WriteCounter struct {
+	Status                   *Progress
+	Target                   io.Writer
+	processed, Size, counter uint64
+}
+
+func (s *WriteCounter) ReadAll(source io.Reader) (err error) {
+	s.counter = uint64(0)
+	if s.Target == nil {
+		return errors.New("can not read all, target unset")
+	}
+	if source == nil {
+		return errors.New("can not read all, source unset")
+	}
+	_, err = io.Copy(s.Target, io.TeeReader(source, s))
+	return
+}
+
+func (s *WriteCounter) Write(p []byte) (int, error) {
+	if s.Status != nil && s.Size != 0 {
+		s.processed += uint64(len(p))
+		fraction := float32(s.processed) / float32(s.Size)
+		if s.counter%uint64(100) == 0 || fraction == 1. {
+			s.Status.UpdateProcessed(fraction)
+		}
+	}
+	s.counter++
+	return len(p), nil
+}