Add support for JSON log formatting (#1231)

Signed-off-by: Michael Pilat <[email protected]>

Author: mikepilat

cmd/main.go

@@ -36,6 +36,7 @@ type ImageUpdaterConfig struct {
 	CheckInterval          time.Duration
 	ArgoClient             argocd.ArgoCD
 	LogLevel               string
+	LogFormat              string
 	KubeClient             *kube.ImageUpdaterKubernetesClient
 	MaxConcurrency         int
 	HealthPort             int

cmd/run.go

@@ -51,6 +51,17 @@ func newRunCommand() *cobra.Command {
 				return err
 			}
 
+			var logFormat log.LogFormat
+			switch cfg.LogFormat {
+			case "text":
+				logFormat = log.LogFormatText
+			case "json":
+				logFormat = log.LogFormatJSON
+			default:
+				return fmt.Errorf("Invalid log format '%s'", cfg.LogFormat)
+			}
+			log.SetLogFormat(logFormat)
+
 			if once {
 				cfg.CheckInterval = 0
 				cfg.HealthPort = 0
@@ -323,6 +334,7 @@ func newRunCommand() *cobra.Command {
 	runCmd.Flags().BoolVar(&cfg.DryRun, "dry-run", false, "run in dry-run mode. If set to true, do not perform any changes")
 	runCmd.Flags().DurationVar(&cfg.CheckInterval, "interval", env.GetDurationVal("IMAGE_UPDATER_INTERVAL", 2*time.Minute), "interval for how often to check for updates")
 	runCmd.Flags().StringVar(&cfg.LogLevel, "loglevel", env.GetStringVal("IMAGE_UPDATER_LOGLEVEL", "info"), "set the loglevel to one of trace|debug|info|warn|error")
+	runCmd.Flags().StringVar(&cfg.LogFormat, "logformat", env.GetStringVal("IMAGE_UPDATER_LOGFORMAT", "text"), "set the log format to one of text|json")
 	runCmd.Flags().StringVar(&kubeConfig, "kubeconfig", "", "full path to kubernetes client configuration, i.e. ~/.kube/config")
 	runCmd.Flags().IntVar(&cfg.HealthPort, "health-port", 8080, "port to start the health server on, 0 to disable")
 	runCmd.Flags().IntVar(&cfg.MetricsPort, "metrics-port", 8081, "port to start the metrics server on, 0 to disable")

cmd/run_test.go

@@ -26,6 +26,7 @@ func TestNewRunCommand(t *testing.T) {
 	asser.Equal("false", runCmd.Flag("dry-run").Value.String())
 	asser.Equal(env.GetDurationVal("IMAGE_UPDATER_INTERVAL", 2*time.Minute).String(), runCmd.Flag("interval").Value.String())
 	asser.Equal(env.GetStringVal("IMAGE_UPDATER_LOGLEVEL", "info"), runCmd.Flag("loglevel").Value.String())
+	asser.Equal(env.GetStringVal("IMAGE_UPDATER_LOGFORMAT", "text"), runCmd.Flag("logformat").Value.String())
 	asser.Equal("", runCmd.Flag("kubeconfig").Value.String())
 	asser.Equal("8080", runCmd.Flag("health-port").Value.String())
 	asser.Equal("8081", runCmd.Flag("metrics-port").Value.String())

docs/install/cmd/run.md

@@ -195,6 +195,12 @@ Set the log level to *level*, where *level* can be one of `trace`, `debug`,
 
 Can also be set using the *IMAGE_UPDATER_LOGLEVEL* environment variable.
 
+**--logformat *format***
+
+Set the log format to *format*, where *format* can be one of `text` or `json`
+
+Can also be set using the *IMAGE_UPDATER_LOGFORMAT* environment variable.
+
 **--match-application-label *selector***
 
 Only process applications that have a valid annotation and match the given

registry-scanner/pkg/log/log.go

@@ -61,6 +61,22 @@ func SetLogLevel(logLevel string) error {
 	return nil
 }
 
+type LogFormat int
+
+const (
+	LogFormatText LogFormat = iota
+	LogFormatJSON
+)
+
+func SetLogFormat(logFormat LogFormat) {
+	switch logFormat {
+	case LogFormatText:
+		logger.SetFormatter(&logrus.TextFormatter{DisableColors: disableLogColors()})
+	case LogFormatJSON:
+		logger.SetFormatter(&logrus.JSONFormatter{})
+	}
+}
+
 // WithContext is an alias for NewContext
 func WithContext() *LogContext {
 	return NewContext()

registry-scanner/pkg/log/log_test.go

@@ -1,6 +1,7 @@
 package log
 
 import (
+	"encoding/json"
 	"fmt"
 	"testing"
 
@@ -154,3 +155,31 @@ func Test_LogLevel(t *testing.T) {
 		assert.Error(t, err)
 	})
 }
+
+func Test_LogFormatJSON(t *testing.T) {
+	// We need tracing level
+	Log().SetLevel(logrus.TraceLevel)
+
+	t.Run("Test set text log format", func(t *testing.T) {
+		SetLogFormat(LogFormatText)
+		out, err := fixture.CaptureStdout(func() {
+			WithContext().AddField("foo", "bar").Infof("this is a test")
+		})
+		assert.NoError(t, err)
+		assert.Contains(t, out, "foo=bar")
+		assert.Contains(t, out, "msg=\"this is a test\"")
+	})
+	t.Run("Test set JSON log format", func(t *testing.T) {
+		SetLogFormat(LogFormatJSON)
+		out, err := fixture.CaptureStdout(func() {
+			WithContext().AddField("foo", "bar").Warnf("this is a test")
+		})
+		assert.NoError(t, err)
+
+		var data map[string]any
+		err = json.Unmarshal([]byte(out), &data)
+		assert.NoError(t, err)
+		assert.Equal(t, "bar", data["foo"])
+		assert.Equal(t, "this is a test", data["msg"])
+	})
+}