Function NewLogger

logging/log.go:41–77

NewLogger constructs a log.Logger based on the given format. The support formats are "json" and "logfmt".

(format string)

// NewLogger constructs a log.Logger based on the given format. The support
// formats are "json" and "logfmt".
func NewLogger(format string) (logger log.Logger) {
	switch strings.ToLower(format) {
	case "json":
		logger = log.NewJSONLogger(log.NewSyncWriter(os.Stdout))
		return logger
	default:
		// Color by level value
		colorFn := func(keyvals ...interface{}) term.FgBgColor {
			for i := 0; i < len(keyvals)-1; i += 2 {
				if keyvals[i] != "level" {
					continue
				}
				if value, ok := keyvals[i+1].(level.Value); ok {
					switch value.String() {
					case "debug":
						return term.FgBgColor{Fg: term.DarkGray}
					case "info":
						return term.FgBgColor{Fg: term.Gray}
					case "warn":
						return term.FgBgColor{Fg: term.Yellow}
					case "error":
						return term.FgBgColor{Fg: term.Red}
					case "crit":
						return term.FgBgColor{Fg: term.Gray, Bg: term.DarkRed}
					default:
						return term.FgBgColor{}
					}
				}
			}
			return term.FgBgColor{}
		}
		logger = term.NewLogger(os.Stdout, log.NewLogfmtLogger, colorFn)
		logger = log.With(log.NewSyncLogger(logger), "ts", log.DefaultTimestamp)

		return logger
	}
}

// LevelFilter filters the log output based on its level.
// Allowed levels are "debug", "info", "warn", "error", or "none"