New() — fiber Function Reference

Architecture documentation for the New() function in logger.go from the fiber codebase.

Function go FiberCore Adapters

Entity Profile

FiberCore→ Adapters→ New() — fiber Function Reference

Dependency Diagram

graph TD
  8513b76d_62e4_0900_954b_208af005a9e6["New()"]
  c05699f8_10c4_dc5d_e4d2_14ff886537f1["logger.go"]
  8513b76d_62e4_0900_954b_208af005a9e6 -->|defined in| c05699f8_10c4_dc5d_e4d2_14ff886537f1
  style 8513b76d_62e4_0900_954b_208af005a9e6 fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

middleware/logger/logger.go lines 15–127

func New(config ...Config) fiber.Handler {
	// Set default config
	cfg := configDefault(config...)

	// Get timezone location
	tz, err := time.LoadLocation(cfg.TimeZone)
	if err != nil || tz == nil {
		cfg.timeZoneLocation = time.Local
	} else {
		cfg.timeZoneLocation = tz
	}

	// Check if format contains latency
	cfg.enableLatency = strings.Contains(cfg.Format, "${"+TagLatency+"}")

	var timestamp atomic.Value
	// Create correct timeformat
	timestamp.Store(time.Now().In(cfg.timeZoneLocation).Format(cfg.TimeFormat))

	// Update date/time every 500 milliseconds in a separate go routine
	if strings.Contains(cfg.Format, "${"+TagTime+"}") {
		go func() {
			for {
				time.Sleep(cfg.TimeInterval)
				timestamp.Store(time.Now().In(cfg.timeZoneLocation).Format(cfg.TimeFormat))
			}
		}()
	}
	// Set PID once
	pid := strconv.Itoa(os.Getpid())

	// Set variables
	var (
		once       sync.Once
		errHandler fiber.ErrorHandler

		dataPool = sync.Pool{New: func() any { return new(Data) }}
	)

	// Err padding
	errPadding := 15
	errPaddingStr := strconv.Itoa(errPadding)

	// Before handling func
	cfg.BeforeHandlerFunc(&cfg)

	// Logger data
	// instead of analyzing the template inside(handler) each time, this is done once before
	// and we create several slices of the same length with the functions to be executed and fixed parts.
	templateChain, logFunChain, err := buildLogFuncChain(&cfg, createTagMap(&cfg))
	if err != nil {
		panic(err)
	}

	// Return new handler
	return func(c fiber.Ctx) error {
		// Don't execute middleware if Next returns true
		if cfg.Next != nil && cfg.Next(c) {
			return c.Next()
		}

		// Set error handler once
		once.Do(func() {
			// get longest possible path
			stack := c.App().Stack()
			for m := range stack {
				for r := range stack[m] {
					if len(stack[m][r].Path) > errPadding {
						errPadding = len(stack[m][r].Path)
						errPaddingStr = strconv.Itoa(errPadding)
					}
				}
			}
			// override error handler
			errHandler = c.App().ErrorHandler
		})

		// Logger data
		data := dataPool.Get().(*Data) //nolint:forcetypeassert,errcheck // We store nothing else in the pool
		// no need for a reset, as long as we always override everything
		data.Pid = pid