loggerConfig supports request body

logger.go

@@ -5,6 +5,7 @@
 package gin
 
 import (
+	"bytes"
 	"fmt"
 	"io"
 	"net/http"
@@ -47,6 +48,10 @@ type LoggerConfig struct {
 	// SkipPaths is an url path array which logs are not written.
 	// Optional.
 	SkipPaths []string
+
+	// RequestBody is a bool to enable request body logging
+	// Optional. Default value is false
+	RequestBody bool
 }
 
 // LogFormatter gives the signature of the formatter function passed to LoggerWithFormatter
@@ -236,11 +241,20 @@ func LoggerWithConfig(conf LoggerConfig) HandlerFunc {
 		path := c.Request.URL.Path
 		raw := c.Request.URL.RawQuery
 
+		var body []byte
+		if conf.RequestBody {
+			body, _ = io.ReadAll(c.Request.Body)
+			c.Request.Body = io.NopCloser(bytes.NewBuffer(body))
+		}
+
 		// Process request
 		c.Next()
 
 		// Log only when path is not being skipped
 		if _, ok := skip[path]; !ok {
+			if conf.RequestBody {
+				c.Request.Body = io.NopCloser(bytes.NewBuffer(body))
+			}
 			param := LogFormatterParams{
 				Request: c.Request,
 				isTerm:  isTerm,

logger_test.go

@@ -5,8 +5,10 @@
 package gin
 
 import (
+	"bytes"
 	"errors"
 	"fmt"
+	"io"
 	"net/http"
 	"strings"
 	"testing"
@@ -182,25 +184,29 @@ func TestLoggerWithFormatter(t *testing.T) {
 func TestLoggerWithConfigFormatting(t *testing.T) {
 	var gotParam LogFormatterParams
 	var gotKeys map[string]any
+	var gotBody []byte
 	buffer := new(strings.Builder)
 
 	router := New()
 	router.engine.trustedCIDRs, _ = router.engine.prepareTrustedCIDRs()
 
 	router.Use(LoggerWithConfig(LoggerConfig{
-		Output: buffer,
+		Output:      buffer,
+		RequestBody: true,
 		Formatter: func(param LogFormatterParams) string {
 			// for assert test
 			gotParam = param
+			gotBody, _ = io.ReadAll(param.Request.Body)
 
-			return fmt.Sprintf("[FORMATTER TEST] %v | %3d | %13v | %15s | %-7s %s\n%s",
+			return fmt.Sprintf("[FORMATTER TEST] %v | %3d | %13v | %15s | %-7s %s %s\n%s",
 				param.TimeStamp.Format("2006/01/02 - 15:04:05"),
 				param.StatusCode,
 				param.Latency,
 				param.ClientIP,
 				param.Method,
 				param.Path,
 				param.ErrorMessage,
+				string(gotBody),
 			)
 		},
 	}))
@@ -229,6 +235,16 @@ func TestLoggerWithConfigFormatting(t *testing.T) {
 	assert.Equal(t, "/example?a=100", gotParam.Path)
 	assert.Empty(t, gotParam.ErrorMessage)
 	assert.Equal(t, gotKeys, gotParam.Keys)
+
+	router.POST("/example", func(c *Context) {
+		// set dummy ClientIP
+		c.Request.Header.Set("X-Forwarded-For", "20.20.20.20")
+		time.Sleep(time.Millisecond)
+	})
+	PerformBodyRequest(router, "POST", "/example", []header{}, bytes.NewBufferString(`{"name":"test"}`))
+
+	// LogFormatterParams post body test
+	assert.Equal(t, string(gotBody), `{"name":"test"}`)
 }
 
 func TestDefaultLogFormatter(t *testing.T) {

routes_test.go

@@ -6,6 +6,7 @@ package gin
 
 import (
 	"fmt"
+	"io"
 	"net/http"
 	"net/http/httptest"
 	"os"
@@ -30,7 +31,15 @@ func PerformRequest(r http.Handler, method, path string, headers ...header) *htt
 	r.ServeHTTP(w, req)
 	return w
 }
-
+func PerformBodyRequest(r http.Handler, method, path string, headers []header, body io.Reader) *httptest.ResponseRecorder {
+	req := httptest.NewRequest(method, path, body)
+	for _, h := range headers {
+		req.Header.Add(h.Key, h.Value)
+	}
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, req)
+	return w
+}
 func testRouteOK(method string, t *testing.T) {
 	passed := false
 	passedAny := false