cmd/osbuild-composer: journald support

cmd/osbuild-composer/config.go

@@ -129,7 +129,7 @@ func GetDefaultConfig() *ComposerConfigFile {
 			"rhel-10": "rhel-10.0",
 		},
 		LogLevel:  "info",
-		LogFormat: "text",
+		LogFormat: "journal",
 		DNFJson:   "/usr/libexec/osbuild-depsolve-dnf",
 	}
 }

cmd/osbuild-composer/config_test.go

@@ -77,7 +77,7 @@ func TestDefaultConfig(t *testing.T) {
 	}
 	require.Equal(t, expectedDistroAliases, defaultConfig.DistroAliases)
 
-	require.Equal(t, "text", defaultConfig.LogFormat)
+	require.Equal(t, "journal", defaultConfig.LogFormat)
 }
 
 func TestConfig(t *testing.T) {

cmd/osbuild-composer/main.go

@@ -3,11 +3,15 @@ package main
 import (
 	"context"
 	"flag"
+	"io"
+	"log"
 	"os"
 
 	"github.com/coreos/go-systemd/activation"
+	"github.com/coreos/go-systemd/journal"
 	"github.com/getsentry/sentry-go"
 	sentrylogrus "github.com/getsentry/sentry-go/logrus"
+	"github.com/osbuild/osbuild-composer/internal/common"
 	slogger "github.com/osbuild/osbuild-composer/pkg/splunk_logger"
 	"github.com/sirupsen/logrus"
 )
@@ -28,6 +32,11 @@ func main() {
 	flag.BoolVar(&verbose, "verbose", false, "Print access log")
 	flag.Parse()
 
+	// Redirect Go standard logger into logrus before it's used by other packages
+	log.SetOutput(common.Logger())
+	// Ensure the Go standard logger does not have any prefix or timestamp
+	log.SetFlags(0)
+
 	if !verbose {
 		logrus.Print("verbose flag is provided for backward compatibility only, current behavior is always printing the access log")
 	}
@@ -49,6 +58,16 @@ func main() {
 	}
 
 	switch config.LogFormat {
+	case "journal":
+		// If we are running under systemd, use the journal. Otherwise,
+		// fallback to text formatter.
+		if journal.Enabled() {
+			logrus.SetFormatter(&logrus.JSONFormatter{})
+			logrus.AddHook(&common.JournalHook{})
+			logrus.SetOutput(io.Discard)
+		} else {
+			logrus.SetFormatter(&logrus.TextFormatter{})
+		}
 	case "text":
 		logrus.SetFormatter(&logrus.TextFormatter{})
 	case "json":