implement structured logging

utils/logging.go

@@ -0,0 +1,68 @@
+package utils
+
+import (
+	"io"
+	"os"
+	"strings"
+	"time"
+
+	"github.com/rs/zerolog"
+	"github.com/rs/zerolog/log"
+)
+
+type LogWriter struct {
+	Logger zerolog.Logger
+}
+
+func (lw LogWriter) Write(bs []byte) (int, error) {
+	return lw.Logger.With().Str("level", "info").Logger().Write(bs)
+}
+
+func SetupJSONLogger(levelStr string, w io.Writer) {
+	// zerolog.SetGlobalLevel(GetLogLevelOrDebug(levelStr))
+
+	zerolog.MessageFieldName = "message"
+	zerolog.LevelFieldName = "level"
+	// zerolog.TimestampFieldName= "time"
+
+	var tsHook timestampHook
+	log.Logger = zerolog.New(w).
+		Hook(&tsHook).
+		Level(GetLogLevelOrDebug(levelStr))
+}
+
+func SetupDefaultLogger(levelStr string) {
+	zerolog.MessageFieldName = "message"
+	zerolog.LevelFieldName = "level"
+
+	log.Logger = zerolog.New(zerolog.ConsoleWriter{Out: os.Stderr, TimeFormat: time.RFC3339}).
+		Level(GetLogLevelOrDebug(levelStr)).
+		With().
+		Timestamp().
+		Logger()
+}
+
+func GetLogLevelOrDebug(levelStr string) zerolog.Level {
+	levelStr = strings.ToLower(levelStr)
+	if levelStr == "warning" {
+		levelStr = "warn"
+	}
+
+	var level zerolog.Level
+
+	err := level.UnmarshalText([]byte(levelStr))
+	if err == nil {
+		return level
+	}
+
+	log.Warn().Msgf("Unknown log level '%s', defaulting to debug", levelStr)
+	return zerolog.DebugLevel
+}
+
+type timestampHook struct{}
+
+func (h *timestampHook) Run(e *zerolog.Event, l zerolog.Level, msg string) {
+	t := time.Now()
+	ts := t.Format(time.RFC3339)
+	e.Str("time", ts)
+}