switch to UTC on flag

intlogger.go

@@ -60,6 +60,7 @@ type intLogger struct {
 	callerOffset int
 	name         string
 	timeFormat   string
+	useUtcTime   bool
 	disableTime  bool
 
 	// This is an interface so that it's shared by any derived loggers, since
@@ -116,6 +117,7 @@ func newLogger(opts *LoggerOptions) *intLogger {
 		json:              opts.JSONFormat,
 		name:              opts.Name,
 		timeFormat:        TimeFormat,
+		useUtcTime:        opts.UTCTime,
 		disableTime:       opts.DisableTime,
 		mutex:             mutex,
 		writer:            newWriter(output, opts.Color),
@@ -153,6 +155,9 @@ func (l *intLogger) log(name string, level Level, msg string, args ...interface{
 	}
 
 	t := time.Now()
+	if l.useUtcTime {
+		t = t.UTC()
+	}
 
 	l.mutex.Lock()
 	defer l.mutex.Unlock()

logger.go

@@ -248,6 +248,9 @@ type LoggerOptions struct {
 	// The time format to use instead of the default
 	TimeFormat string
 
+	// Control whether to use UTC instead of the default local time-zone
+	UTCTime bool
+
 	// Control whether or not to display the time at all. This is required
 	// because setting TimeFormat to empty assumes the default format.
 	DisableTime bool

logger_test.go

@@ -249,6 +249,24 @@ func TestLogger(t *testing.T) {
 		assert.Equal(t, str[:dataIdx], time.Now().Format(time.Kitchen))
 	})
 
+	t.Run("use UTC time zone", func(t *testing.T) {
+		var buf bytes.Buffer
+
+		logger := New(&LoggerOptions{
+			Name:       "test",
+			Output:     &buf,
+			TimeFormat: time.Kitchen,
+			UTCTime:    true,
+		})
+
+		logger.Info("this is test", "who", "programmer", "why", "testing is fun")
+
+		str := buf.String()
+		dataIdx := strings.IndexByte(str, ' ')
+
+		assert.Equal(t, str[:dataIdx], time.Now().UTC().Format(time.Kitchen))
+	})
+
 	t.Run("respects DisableTime", func(t *testing.T) {
 		var buf bytes.Buffer
 
@@ -657,6 +675,34 @@ func TestLogger_JSON(t *testing.T) {
 		assert.Equal(t, val, time.Now().Format(time.Kitchen))
 	})
 
+	t.Run("use UTC time zone", func(t *testing.T) {
+		var buf bytes.Buffer
+
+		logger := New(&LoggerOptions{
+			Name:       "test",
+			Output:     &buf,
+			JSONFormat: true,
+			TimeFormat: time.Kitchen,
+			UTCTime:    true,
+		})
+
+		logger.Info("Lacatan banana")
+
+		b := buf.Bytes()
+
+		var raw map[string]interface{}
+		if err := json.Unmarshal(b, &raw); err != nil {
+			t.Fatal(err)
+		}
+
+		val, ok := raw["@timestamp"]
+		if !ok {
+			t.Fatal("missing '@timestamp' key")
+		}
+
+		assert.Equal(t, val, time.Now().UTC().Format(time.Kitchen))
+	})
+
 	t.Run("respects DisableTime", func(t *testing.T) {
 		var buf bytes.Buffer
 		logger := New(&LoggerOptions{