🔥 Add logger middleware time zone support

middleware/logger.go

@@ -60,6 +60,11 @@ type (
 		// Optional. Default: 15:04:05
 		TimeFormat string
 
+		// TimeZone can be specified, such as "UTC" and "America/New_York" and "Asia/Chongqing", etc
+		//
+		// Optional. Default: Local
+		TimeZone string
+
 		// Output is a writter where logs are written
 		//
 		// Default: os.Stderr
@@ -133,6 +138,7 @@ var LoggerConfigDefault = LoggerConfig{
 	Next:       nil,
 	Format:     "#${pid} - ${time} ${status} - ${latency} ${method} ${path}\n",
 	TimeFormat: "2006/01/02 15:04:05",
+	TimeZone:   "Local",
 	Output:     os.Stderr,
 }
 
@@ -142,6 +148,7 @@ Logger allows the following config arguments in any order:
 	- Logger(next func(*fiber.Ctx) bool)
 	- Logger(output io.Writer)
 	- Logger(format string)
+	- Logger(timeZone string)
 	- Logger(timeFormat string)
 	- Logger(config LoggerConfig)
 */
@@ -157,6 +164,8 @@ func Logger(options ...interface{}) fiber.Handler {
 			case string:
 				if strings.Contains(opt, "${") {
 					config.Format = opt
+				} else if isTimeZone(opt) {
+					config.TimeZone = opt
 				} else {
 					config.TimeFormat = opt
 				}
@@ -184,6 +193,9 @@ func logger(config LoggerConfig) fiber.Handler {
 	if config.Format == "" {
 		config.Format = LoggerConfigDefault.Format
 	}
+	if config.TimeZone == "" {
+		config.TimeZone = LoggerConfigDefault.TimeZone
+	}
 	if config.TimeFormat == "" {
 		config.TimeFormat = LoggerConfigDefault.TimeFormat
 	}
@@ -203,14 +215,13 @@ func logger(config LoggerConfig) fiber.Handler {
 
 	var tmpl loggerTemplate
 	tmpl.new(config.Format, "${", "}")
-
-	timestamp := time.Now().Format(config.TimeFormat)
+	timestamp := nowTimeString(config.TimeZone, config.TimeFormat)
 	// Update date/time every second in a separate go routine
 	if strings.Contains(config.Format, "${time}") {
 		go func() {
 			for {
 				mutex.Lock()
-				timestamp = time.Now().Format(config.TimeFormat)
+				timestamp = nowTimeString(config.TimeZone, config.TimeFormat)
 				mutex.Unlock()
 				time.Sleep(500 * time.Millisecond)
 			}
@@ -354,6 +365,24 @@ func logger(config LoggerConfig) fiber.Handler {
 	}
 }
 
+func nowTimeString(timeZone, layout string) string {
+	// This is different from Golang's time package which returns UTC, and Local is better than it
+	if timeZone == "" {
+		timeZone = "UTC"
+	}
+	location, err := time.LoadLocation(timeZone)
+	if err != nil {
+		log.Fatalf("Logger: failed to load time zone: %e\n", err)
+	}
+	return time.Now().In(location).Format(layout)
+}
+
+// Use Golang's time package to determine whether the TimeZone is available
+func isTimeZone(name string) bool {
+	_, err := time.LoadLocation(name)
+	return err == nil
+}
+
 // MIT License fasttemplate
 // Copyright (c) 2015 Aliaksandr Valialkin
 // https://github.com/valyala/fasttemplate/blob/master/LICENSE

middleware/logger.md

@@ -18,6 +18,9 @@ func main() {
   // Pass a custom output
   app.Use(middleware.Logger(os.Stdout))
 
+  // Pass a custom time zone
+  app.Use(middleware.Logger("UTC"))
+
   // Pass a custom timeformat
   app.Use(middleware.Logger("15:04:05"))
 
@@ -34,6 +37,7 @@ func main() {
   app.Use(middleware.Logger(middleware.LoggerConfig{
       Format:     "${time} ${method} ${path}",
       TimeFormat: "15:04:05",
+      TimeZone:   "Asia/Chongqing",
       Output:     os.Stdout,
   }))
 
@@ -87,6 +91,11 @@ type LoggerConfig struct {
   // Optional. Default: 15:04:05
   TimeFormat string
 
+  // TimeZone can be specified, such as "UTC" and "America/New_York" and "Asia/Chongqing", etc
+  //
+  // Optional. Default: Local
+  TimeZone string
+
   // Output is a writter where logs are written
   //
   // Default: os.Stderr

middleware/logger_test.go

@@ -104,6 +104,7 @@ func Test_Middleware_Logger_Options_And_WithConfig(t *testing.T) {
 		Logger("15:04:05"),
 		Logger("${time} ${method} ${path} - ${ip} - ${status} - ${latency}\n"),
 		Logger(LoggerConfig{Output: buf}),
+		Logger("UTC"),
 	}
 
 	for i, logger := range loggers {
@@ -128,10 +129,61 @@ func Test_Middleware_Logger_Options_And_WithConfig(t *testing.T) {
 			utils.AssertEqual(t, 51, len(res), fmt.Sprintf("Has length: %v, expected: %v, raw: %s", len(res), 51, res))
 		} else if i == 3 {
 			utils.AssertEqual(t, 48, len(res), fmt.Sprintf("Has length: %v, expected: %v, raw: %s", len(res), 48, res))
+		} else if i == 4 {
+			utils.AssertEqual(t, 48, len(res), fmt.Sprintf("Has length: %v, expected: %v, raw: %s", len(res), 48, res))
 		}
 	}
 }
 
+func Test_isTimeZone(t *testing.T) {
+	type args struct {
+		name string
+	}
+	tests := []struct {
+		name string
+		args args
+		want bool
+	}{
+		{
+			"Empty",
+			args{""},
+			true,
+		},
+		{
+			"Local",
+			args{name: "Local"},
+			true,
+		},
+		{
+			"UTC",
+			args{name: "UTC"},
+			true,
+		},
+		{
+			"America/New_York",
+			args{name: "America/New_York"},
+			true,
+		},
+		{
+			"Asia/Chongqing",
+			args{"Asia/Chongqing"},
+			true,
+		},
+		{
+			"Time format",
+			args{name: "2006-01-02 15:04:05"},
+			false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := isTimeZone(tt.args.name); got != tt.want {
+				t.Errorf("isTimeZone() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
 // go test -v -run=^$ -bench=Benchmark_Middleware_Logger -benchmem -count=4
 func Benchmark_Middleware_Logger(b *testing.B) {