💼 add locals to logger

Co-Authored-By: Rafael Cossovan <navossoc@gmail.com>

middleware/logger/README.md

@@ -103,6 +103,7 @@ const (
 	TagQuery         = "query:"
 	TagForm          = "form:"
 	TagCookie        = "cookie:"
+	TagLocals        = "locals:"
 	TagBlack         = "black"
 	TagRed           = "red"
 	TagGreen         = "green"

middleware/logger/logger.go

@@ -79,6 +79,7 @@ const (
 	TagRoute         = "route"
 	TagError         = "error"
 	TagHeader        = "header:"
+	TagLocals        = "locals:"
 	TagQuery         = "query:"
 	TagForm          = "form:"
 	TagCookie        = "cookie:"
@@ -332,6 +333,17 @@ func New(config ...Config) fiber.Handler {
 					return buf.WriteString(c.FormValue(tag[5:]))
 				case strings.HasPrefix(tag, TagCookie):
 					return buf.WriteString(c.Cookies(tag[7:]))
+				case strings.HasPrefix(tag, TagLocals):
+					switch v := c.Locals(tag[7:]).(type) {
+					case []byte:
+						return buf.Write(v)
+					case string:
+						return buf.WriteString(v)
+					case nil:
+						return 0, nil
+					default:
+						return buf.WriteString(fmt.Sprintf("%v", v))
+					}
 				}
 			}
 			return 0, nil

middleware/logger/logger_test.go

@@ -36,6 +36,52 @@ func Test_Logger(t *testing.T) {
 	utils.AssertEqual(t, "some random error", buf.String())
 }
 
+// go test -run Test_Logger_locals
+func Test_Logger_locals(t *testing.T) {
+	app := fiber.New()
+
+	buf := bytebufferpool.Get()
+	defer bytebufferpool.Put(buf)
+
+	app.Use(New(Config{
+		Format: "${locals:demo}",
+		Output: buf,
+	}))
+
+	app.Get("/", func(c *fiber.Ctx) error {
+		c.Locals("demo", "johndoe")
+		return c.SendStatus(fiber.StatusOK)
+	})
+
+	app.Get("/int", func(c *fiber.Ctx) error {
+		c.Locals("demo", 55)
+		return c.SendStatus(fiber.StatusOK)
+	})
+
+	app.Get("/empty", func(c *fiber.Ctx) error {
+		return c.SendStatus(fiber.StatusOK)
+	})
+
+	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	utils.AssertEqual(t, nil, err)
+	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
+	utils.AssertEqual(t, "johndoe", buf.String())
+
+	buf.Reset()
+
+	resp, err = app.Test(httptest.NewRequest("GET", "/int", nil))
+	utils.AssertEqual(t, nil, err)
+	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
+	utils.AssertEqual(t, "55", buf.String())
+
+	buf.Reset()
+
+	resp, err = app.Test(httptest.NewRequest("GET", "/empty", nil))
+	utils.AssertEqual(t, nil, err)
+	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
+	utils.AssertEqual(t, "", buf.String())
+}
+
 // go test -run Test_Logger_Next
 func Test_Logger_Next(t *testing.T) {
 	app := fiber.New()
@@ -130,10 +176,9 @@ func Benchmark_Logger(b *testing.B) {
 	app := fiber.New()
 
 	app.Use(New(Config{
-		Format: "${bytesReceived} ${bytesSent} ${status}",
+		Format: "${path}",
 		Output: ioutil.Discard,
 	}))
-
 	app.Get("/", func(c *fiber.Ctx) error {
 		return c.SendString("Hello, World!")
 	})