feat(GODT-2691): close logrus output file on exit.

internal/app/app.go

@@ -19,6 +19,7 @@ package app
 
 import (
 	"fmt"
+	"io"
 	"net/http"
 	"net/http/cookiejar"
 	"net/url"
@@ -189,6 +190,11 @@ func run(c *cli.Context) error {
 		exe = os.Args[0]
 	}
 
+	var logCloser io.Closer
+	defer func() {
+		_ = logging.Close(logCloser)
+	}()
+
 	// Restart the app if requested.
 	return withRestarter(exe, func(restarter *restarter.Restarter) error {
 		// Handle crashes with various actions.
@@ -205,7 +211,9 @@ func run(c *cli.Context) error {
 					}
 
 					// Initialize logging.
-					return withLogging(c, crashHandler, locations, func() error {
+					return withLogging(c, crashHandler, locations, func(closer io.Closer) error {
+						logCloser = closer
+
 						// If there was an error during migration, log it now.
 						if migrationErr != nil {
 							logrus.WithError(migrationErr).Error("Failed to migrate old app data")
@@ -304,7 +312,7 @@ func withSingleInstance(settingPath, lockFile string, version *semver.Version, f
 }
 
 // Initialize our logging system.
-func withLogging(c *cli.Context, crashHandler *crash.Handler, locations *locations.Locations, fn func() error) error {
+func withLogging(c *cli.Context, crashHandler *crash.Handler, locations *locations.Locations, fn func(closer io.Closer) error) error {
 	logrus.Debug("Initializing logging")
 	defer logrus.Debug("Logging stopped")
 
@@ -318,7 +326,8 @@ func withLogging(c *cli.Context, crashHandler *crash.Handler, locations *locatio
 
 	// Initialize logging.
 	sessionID := logging.NewSessionIDFromString(c.String(flagSessionID))
-	if err := logging.Init(
+	var closer io.Closer
+	if closer, err = logging.Init(
 		logsPath,
 		sessionID,
 		logging.BridgeShortAppName,
@@ -343,7 +352,7 @@ func withLogging(c *cli.Context, crashHandler *crash.Handler, locations *locatio
 		WithField("SentryID", sentry.GetProtectedHostname()).
 		Info("Run app")
 
-	return fn()
+	return fn(closer)
 }
 
 // WithLocations provides access to locations where we store our files.

internal/logging/logging.go

@@ -21,6 +21,7 @@ import (
 	"bytes"
 	"context"
 	"errors"
+	"io"
 	"os"
 	"path/filepath"
 	"regexp"
@@ -88,7 +89,7 @@ func (cs *coloredStdOutHook) Fire(entry *logrus.Entry) error {
 
 // Init Initialize logging. Log files are rotated when their size exceeds rotationSize. if pruningSize >= 0, pruning occurs using
 // the default pruning algorithm.
-func Init(logsPath string, sessionID SessionID, appName AppName, rotationSize, pruningSize int64, level string) error {
+func Init(logsPath string, sessionID SessionID, appName AppName, rotationSize, pruningSize int64, level string) (io.Closer, error) {
 	logrus.SetFormatter(&logrus.TextFormatter{
 		DisableColors:   true,
 		FullTimestamp:   true,
@@ -99,12 +100,22 @@ func Init(logsPath string, sessionID SessionID, appName AppName, rotationSize, p
 
 	rotator, err := NewDefaultRotator(logsPath, sessionID, appName, rotationSize, pruningSize)
 	if err != nil {
-		return err
+		return nil, err
 	}
 
 	logrus.SetOutput(rotator)
 
-	return setLevel(level)
+	return rotator, setLevel(level)
+}
+
+// Close closes the log file. if closer is nil, no error is reported.
+func Close(closer io.Closer) error {
+	if closer == nil {
+		return nil
+	}
+
+	logrus.SetOutput(os.Stdout)
+	return closer.Close()
 }
 
 // ZipLogsForBugReport returns an archive containing the logs for bug report.

internal/logging/logging_test.go

@@ -23,6 +23,7 @@ import (
 	"testing"
 
 	"github.com/ProtonMail/proton-bridge/v3/internal/constants"
+	"github.com/sirupsen/logrus"
 	"github.com/stretchr/testify/require"
 )
 
@@ -93,3 +94,12 @@ func TestLogging_GetOrderedLogFileListForBugReport(t *testing.T) {
 		filepath.Join(dir, string(sessionID1)+"_lau_000"+fileSuffix),
 	}, filePaths)
 }
+
+func TestLogging_Close(t *testing.T) {
+	d := t.TempDir()
+	closer, err := Init(d, NewSessionID(), constants.AppName, 1, DefaultPruningSize, "debug")
+	require.NoError(t, err)
+	logrus.Debug("Test") // because we set max log file size to 1, this will force a rotation of the log file.
+	require.NotNil(t, closer)
+	require.NoError(t, closer.Close())
+}

internal/logging/rotator.go

@@ -86,6 +86,14 @@ func (r *Rotator) Write(p []byte) (int, error) {
 	return n, nil
 }
 
+func (r *Rotator) Close() error {
+	if r.wc != nil {
+		return r.wc.Close()
+	}
+
+	return nil
+}
+
 func (r *Rotator) rotate() error {
 	if r.wc != nil {
 		_ = r.wc.Close()