Fix | Emit JSON logs when --log-format is json

cmd/options.go

@@ -664,23 +664,31 @@ func configureLogging(cfg *Config) {
 	// informers", "Configmap/secret informer synced" from util/settings).
 	logrus.SetOutput(io.Discard)
 
-	consoleWriter := zerolog.ConsoleWriter{Out: os.Stdout, NoColor: true}
 	if cfg.Debug {
 		zerolog.SetGlobalLevel(zerolog.DebugLevel)
-		if cfg.LogFormat == "human" {
-			consoleWriter.TimeFormat = time.RFC1123
-		}
 	} else {
 		zerolog.SetGlobalLevel(zerolog.InfoLevel)
-		if cfg.LogFormat == "human" {
-			consoleWriter.PartsExclude = []string{"time", "level"}
-		}
 	}
+	log.Logger = newLogger(cfg, os.Stdout)
+}
+
+// newLogger returns a JSON logger for the json log format, and a console logger otherwise
+func newLogger(cfg *Config, out io.Writer) zerolog.Logger {
+	if cfg.LogFormat == "json" {
+		return zerolog.New(out).With().Timestamp().Logger()
+	}
+
+	consoleWriter := zerolog.ConsoleWriter{Out: out, NoColor: true}
 	if cfg.LogFormat == "human" {
+		if cfg.Debug {
+			consoleWriter.TimeFormat = time.RFC1123
+		} else {
+			consoleWriter.PartsExclude = []string{"time", "level"}
+		}
 		consoleWriter.FormatFieldName = func(i any) string { return fmt.Sprintf("(%s: ", i) }
 		consoleWriter.FormatFieldValue = func(i any) string { return fmt.Sprintf("%s)", i) }
 	}
-	log.Logger = log.Output(consoleWriter)
+	return log.Output(consoleWriter)
 }
 
 // LogConfig logs all the configuration values

cmd/options_test.go

@@ -0,0 +1,34 @@
+package main
+
+import (
+	"bytes"
+	"encoding/json"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestNewLogger_JSON(t *testing.T) {
+	for _, debug := range []bool{false, true} {
+		var buf bytes.Buffer
+		logger := newLogger(&Config{LogFormat: "json", Debug: debug}, &buf)
+		logger.Error().Str("app", "my-app").Msg("failed to render")
+
+		var entry map[string]any
+		require.NoError(t, json.Unmarshal(buf.Bytes(), &entry), "output is not JSON: %q", buf.String())
+		assert.Equal(t, "error", entry["level"])
+		assert.Equal(t, "failed to render", entry["message"])
+		assert.Equal(t, "my-app", entry["app"])
+		assert.Contains(t, entry, "time")
+	}
+}
+
+func TestNewLogger_Human(t *testing.T) {
+	var buf bytes.Buffer
+	logger := newLogger(&Config{LogFormat: "human"}, &buf)
+	logger.Error().Str("app", "my-app").Msg("failed to render")
+
+	assert.Equal(t, "failed to render (app: my-app)", strings.TrimSpace(buf.String()))
+}