Add mirrorBody option to HTTP mirroring

integration/fixtures/k8s/01-traefik-crd.yml

@@ -2506,6 +2506,11 @@ spec:
                       Default value is -1, which means unlimited size.
                     format: int64
                     type: integer
+                  mirrorBody:
+                    description: |-
+                      MirrorBody defines whether the body of the request should be mirrored.
+                      Default value is true.
+                    type: boolean
                   mirrors:
                     description: Mirrors defines the list of mirrors where Traefik
                       will duplicate the traffic.

integration/fixtures/mirror.toml

@@ -28,6 +28,10 @@
     service = "mirrorWithMaxBody"
     rule = "Path(`/whoamiWithMaxBody`)"
 
+  [http.routers.router3]
+    service = "mirrorWithoutBody"
+    rule = "Path(`/whoamiWithoutBody`)"
+
 
 [http.services]
   [http.services.mirror.mirroring]
@@ -49,6 +53,16 @@
     name = "mirror2"
     percent = 50
 
+  [http.services.mirrorWithoutBody.mirroring]
+    service = "service1"
+    mirrorBody = false
+  [[http.services.mirrorWithoutBody.mirroring.mirrors]]
+    name = "mirror1"
+    percent = 10
+  [[http.services.mirrorWithoutBody.mirroring.mirrors]]
+    name = "mirror2"
+    percent = 50
+
 
   [http.services.service1.loadBalancer]
     [[http.services.service1.loadBalancer.servers]]

integration/simple_test.go

@@ -1004,8 +1004,13 @@ func (s *SimpleSuite) TestMirrorWithBody() {
 	_, err = rand.Read(body5)
 	require.NoError(s.T(), err)
 
-	verifyBody := func(req *http.Request) {
+	// forceOkResponse is used to avoid errors when Content-Length is set but no body is received
+	verifyBody := func(req *http.Request, canBodyBeEmpty bool) (forceOkResponse bool) {
 		b, _ := io.ReadAll(req.Body)
+		if canBodyBeEmpty && req.Header.Get("NoBody") == "true" {
+			require.Empty(s.T(), b)
+			return true
+		}
 		switch req.Header.Get("Size") {
 		case "20":
 			require.Equal(s.T(), body20, b)
@@ -1014,20 +1019,25 @@ func (s *SimpleSuite) TestMirrorWithBody() {
 		default:
 			s.T().Fatal("Size header not present")
 		}
+		return false
 	}
 
 	main := httptest.NewServer(http.HandlerFunc(func(rw http.ResponseWriter, req *http.Request) {
-		verifyBody(req)
+		verifyBody(req, false)
 		atomic.AddInt32(&count, 1)
 	}))
 
 	mirror1 := httptest.NewServer(http.HandlerFunc(func(rw http.ResponseWriter, req *http.Request) {
-		verifyBody(req)
+		if verifyBody(req, true) {
+			rw.WriteHeader(http.StatusOK)
+		}
 		atomic.AddInt32(&countMirror1, 1)
 	}))
 
 	mirror2 := httptest.NewServer(http.HandlerFunc(func(rw http.ResponseWriter, req *http.Request) {
-		verifyBody(req)
+		if verifyBody(req, true) {
+			rw.WriteHeader(http.StatusOK)
+		}
 		atomic.AddInt32(&countMirror2, 1)
 	}))
 
@@ -1104,6 +1114,28 @@ func (s *SimpleSuite) TestMirrorWithBody() {
 	assert.Equal(s.T(), int32(10), countTotal)
 	assert.Equal(s.T(), int32(0), val1)
 	assert.Equal(s.T(), int32(0), val2)
+
+	atomic.StoreInt32(&count, 0)
+	atomic.StoreInt32(&countMirror1, 0)
+	atomic.StoreInt32(&countMirror2, 0)
+
+	req, err = http.NewRequest(http.MethodGet, "http://127.0.0.1:8000/whoamiWithoutBody", bytes.NewBuffer(body20))
+	require.NoError(s.T(), err)
+	req.Header.Set("Size", "20")
+	req.Header.Set("NoBody", "true")
+	for range 10 {
+		response, err := http.DefaultClient.Do(req)
+		require.NoError(s.T(), err)
+		assert.Equal(s.T(), http.StatusOK, response.StatusCode)
+	}
+
+	countTotal = atomic.LoadInt32(&count)
+	val1 = atomic.LoadInt32(&countMirror1)
+	val2 = atomic.LoadInt32(&countMirror2)
+
+	assert.Equal(s.T(), int32(10), countTotal)
+	assert.Equal(s.T(), int32(1), val1)
+	assert.Equal(s.T(), int32(5), val2)
 }
 
 func (s *SimpleSuite) TestMirrorCanceled() {