🔥 feat: Add support for ForceColors in Logger middleware (#3428)

* Force the use of terminal colors via config option

* docs: add example for forcing terminal colors in logger middleware

* test: add benchmarks for logger middleware with forced colors

* Add ForceColors field to 'whats new'

* Show example in 'whats new'

Author: yorickdewid

docs/middleware/logger.md

@@ -89,6 +89,11 @@ app.Use(logger.New(logger.Config{
     DisableColors: true,
 }))
 
+// Force the use of colors
+app.Use(logger.New(logger.Config{
+    ForceColors: true,
+}))
+
 // Use predefined formats 
 app.Use(logger.New(logger.Config{
     Format: logger.FormatCommon,
@@ -166,6 +171,7 @@ Writing to os.File is goroutine-safe, but if you are using a custom Stream that
 | Stream        | `io.Writer`                                       | Stream is a writer where logs are written.                                                                                                    | `os.Stdout`                                                           |
 | LoggerFunc    | `func(c fiber.Ctx, data *Data, cfg Config) error` | Custom logger function for integration with logging libraries (Zerolog, Zap, Logrus, etc). Defaults to Fiber's default logger if not defined. | `see default_logger.go defaultLoggerInstance`                         |
 | DisableColors | `bool`                                            | DisableColors defines if the logs output should be colorized.                                                                                 | `false`                                                               |
+| ForceColors   | `bool`                                            | ForceColors defines if the logs output should be colorized even when the output is not a terminal.                                             | `false`                                                               |
 
 ## Default Config
 

docs/whats_new.md

@@ -794,6 +794,18 @@ curl "http://localhost:3000/header"
 
 You can find more details about this feature in [/docs/api/log.md](./api/log.md#logger).
 
+`logger.Config` now supports a new field called `ForceColors`. This field allows you to force the logger to always use colors, even if the output is not a terminal. This is useful when you want to ensure that the logs are always colored, regardless of the output destination.
+
+```go
+package main
+
+import "github.com/gofiber/fiber/v3/middleware/logger"
+
+app.Use(logger.New(logger.Config{
+    ForceColors: true,
+}))
+```
+
 ## 🧬 Middlewares
 
 ### Adaptor

middleware/logger/config.go

@@ -89,6 +89,11 @@ type Config struct {
 	// Default: false
 	DisableColors bool
 
+	// ForceColors forces the colors to be enabled even if the output is not a terminal
+	//
+	// Default: false
+	ForceColors bool
+
 	enableColors  bool
 	enableLatency bool
 }
@@ -174,7 +179,7 @@ func configDefault(config ...Config) Config {
 	}
 
 	// Enable colors if no custom format or output is given
-	if !cfg.DisableColors && cfg.Stream == ConfigDefault.Stream {
+	if (!cfg.DisableColors && cfg.Stream == ConfigDefault.Stream) || cfg.ForceColors {
 		cfg.enableColors = true
 	}
 

middleware/logger/default_logger.go

@@ -148,7 +148,7 @@ func beforeHandlerFunc(cfg Config) {
 	// If colors are enabled, check terminal compatibility
 	if cfg.enableColors {
 		cfg.Stream = colorable.NewColorableStdout()
-		if os.Getenv("TERM") == "dumb" || os.Getenv("NO_COLOR") == "1" || (!isatty.IsTerminal(os.Stdout.Fd()) && !isatty.IsCygwinTerminal(os.Stdout.Fd())) {
+		if !cfg.ForceColors && (os.Getenv("TERM") == "dumb" || os.Getenv("NO_COLOR") == "1" || (!isatty.IsTerminal(os.Stdout.Fd()) && !isatty.IsCygwinTerminal(os.Stdout.Fd()))) {
 			cfg.Stream = colorable.NewNonColorable(os.Stdout)
 		}
 	}

middleware/logger/logger_test.go

@@ -1018,6 +1018,32 @@ func Test_Logger_EnableColors(t *testing.T) {
 	require.EqualValues(t, 1, *o)
 }
 
+// go test -run Test_Logger_ForceColors
+func Test_Logger_ForceColors(t *testing.T) {
+	t.Parallel()
+	buf := bytebufferpool.Get()
+	defer bytebufferpool.Put(buf)
+
+	app := fiber.New()
+
+	app.Use(New(Config{
+		Format:        "${ip}${status}${method}${path}${error}\n",
+		Stream:        buf,
+		DisableColors: true,
+		ForceColors:   true,
+	}))
+
+	// Alias colors
+	colors := app.Config().ColorScheme
+
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
+	require.NoError(t, err)
+	require.Equal(t, fiber.StatusNotFound, resp.StatusCode)
+
+	expected := fmt.Sprintf("0.0.0.0%s404%s%sGET%s/%sCannot GET /%s\n", colors.Yellow, colors.Reset, colors.Cyan, colors.Reset, colors.Red, colors.Reset)
+	require.Equal(t, expected, buf.String())
+}
+
 // go test -v -run=^$ -bench=Benchmark_Logger$ -benchmem -count=4
 func Benchmark_Logger(b *testing.B) {
 	b.Run("NoMiddleware", func(bb *testing.B) {
@@ -1064,6 +1090,18 @@ func Benchmark_Logger(b *testing.B) {
 		benchmarkSetup(bb, app, "/")
 	})
 
+	b.Run("DefaultFormatForceColors", func(bb *testing.B) {
+		app := fiber.New()
+		app.Use(New(Config{
+			Stream:      io.Discard,
+			ForceColors: true,
+		}))
+		app.Get("/", func(c fiber.Ctx) error {
+			return c.SendString("Hello, World!")
+		})
+		benchmarkSetup(bb, app, "/")
+	})
+
 	b.Run("DefaultFormatWithFiberLog", func(bb *testing.B) {
 		app := fiber.New()
 		logger := fiberlog.DefaultLogger()
@@ -1245,6 +1283,18 @@ func Benchmark_Logger_Parallel(b *testing.B) {
 		benchmarkSetupParallel(bb, app, "/")
 	})
 
+	b.Run("DefaultFormatForceColors", func(bb *testing.B) {
+		app := fiber.New()
+		app.Use(New(Config{
+			Stream:      io.Discard,
+			ForceColors: true,
+		}))
+		app.Get("/", func(c fiber.Ctx) error {
+			return c.SendString("Hello, World!")
+		})
+		benchmarkSetupParallel(bb, app, "/")
+	})
+
 	b.Run("WithTagParameter", func(bb *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{