logr

a golang logger library

Usage

func TestDefault(t *testing.T) {

	log := Default().SetLevel(DebugLevel)
	err := errors.New("New_ERROR")

	log = log.With(
		"kk", "vv",
		"caller", CallerFile(4, false),
		"gg",
	)

	log.Debug("number=%d", 1)
	log.Info("number=%d", 1)
	log.Warn(err)
	log.Error(err)

	ctx := WithLogger(context.Background(), log)
	subcaller(ctx)
}

func subcaller(ctx context.Context) {
	log := FromContext(ctx)

	log = log.Start() // time cost
	defer log.Stop()

	time.Sleep(532 * time.Millisecond)
	log.Info("account=%d", 100)
}

This code appears to be a Go (golang) package named logr, which defines a Logger interface and provides a default implementation of this interface in the form of a levelLogger struct. The levelLogger struct contains fields for a logger instance, log level, a boolean flag indicating the presence of "valuer" parameters in the logger's context, and a slice of key-value pairs that represent additional context data for the logger.

The Logger interface defines methods for logging messages at different levels (e.g. debug, info, warning, etc.), as well as methods for adding context data to the logger and starting/stopping a timer.

The levelLogger struct provides implementations for these methods. For example, the Log method takes a log level and message string as arguments, and logs the message at the specified log level. The With method allows additional key-value pairs to be added to the logger's context, and returns a new levelLogger instance with the updated context. The Start and Stop methods can be used to measure the duration of some code execution and include that duration in the log output.

Overall, this package provides a simple and flexible interface for logging in Go applications.