Add test to confirm default content type used by core client

Signed-off-by: Monis Khan <[email protected]>

Author: enj

pkg/client/tests/clientset_test.go

@@ -0,0 +1,186 @@
+/*
+Copyright 2024 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package tests
+
+import (
+	"context"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"sync/atomic"
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+
+	autoscalingv1 "k8s.io/api/autoscaling/v1"
+	corev1 "k8s.io/api/core/v1"
+	crv1 "k8s.io/apiextensions-apiserver/examples/client-go/pkg/apis/cr/v1"
+	crv1client "k8s.io/apiextensions-apiserver/examples/client-go/pkg/client/clientset/versioned"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/rest"
+)
+
+func TestClientContentType(t *testing.T) {
+	createPodFunc := func(t *testing.T, config *rest.Config) {
+		client, err := kubernetes.NewForConfig(config)
+		if err != nil {
+			t.Fatalf("failed to create REST client: %v", err)
+		}
+
+		_, err = client.CoreV1().Pods("panda").
+			Create(context.TODO(), &corev1.Pod{ObjectMeta: metav1.ObjectMeta{Name: "snorlax"}}, metav1.CreateOptions{})
+		if err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	updateScaleFunc := func(t *testing.T, config *rest.Config) {
+		client, err := kubernetes.NewForConfig(config)
+		if err != nil {
+			t.Fatalf("failed to create REST client: %v", err)
+		}
+
+		_, err = client.AppsV1().Deployments("panda").
+			UpdateScale(context.TODO(), "snorlax", &autoscalingv1.Scale{ObjectMeta: metav1.ObjectMeta{Name: "snorlax"}}, metav1.UpdateOptions{})
+		if err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	createExampleViaRESTClientFunc := func(t *testing.T, config *rest.Config) {
+		kubeClient, err := kubernetes.NewForConfig(config)
+		if err != nil {
+			t.Fatalf("failed to create REST client: %v", err)
+		}
+
+		client := crv1client.New(kubeClient.CoreV1().RESTClient())
+
+		_, err = client.CrV1().Examples("panda").
+			Create(context.TODO(), &crv1.Example{ObjectMeta: metav1.ObjectMeta{Name: "snorlax"}}, metav1.CreateOptions{})
+		if err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	tests := []struct {
+		name              string
+		createFunc        func(*testing.T, *rest.Config)
+		contentType       string
+		expectedPath      string
+		expectContentType string
+		expectBody        string
+	}{
+		{
+			name:              "default",
+			createFunc:        createPodFunc,
+			contentType:       "",
+			expectedPath:      "/api/v1/namespaces/panda/pods",
+			expectContentType: "application/vnd.kubernetes.protobuf",
+			expectBody:        "k8s\x00\n\t\n\x02v1\x12\x03Pod\x12I\n\x17\n\asnorlax\x12\x00\x1a\x00\"\x00*\x002\x008\x00B\x00\x12\x1c\x1a\x002\x00B\x00J\x00R\x00X\x00`\x00h\x00\x82\x01\x00\x8a\x01\x00\x9a\x01\x00\xc2\x01\x00\x1a\x10\n\x00\x1a\x00\"\x00*\x002\x00J\x00Z\x00r\x00\x1a\x00\"\x00",
+		},
+		{
+			name:              "json",
+			createFunc:        createPodFunc,
+			contentType:       "application/json",
+			expectedPath:      "/api/v1/namespaces/panda/pods",
+			expectContentType: "application/json",
+			expectBody: `{"kind":"Pod","apiVersion":"v1","metadata":{"name":"snorlax","creationTimestamp":null},"spec":{"containers":null},"status":{}}
+`,
+		},
+		{
+			name:              "default update scale",
+			createFunc:        updateScaleFunc,
+			contentType:       "",
+			expectedPath:      "/apis/apps/v1/namespaces/panda/deployments/snorlax/scale",
+			expectContentType: "application/vnd.kubernetes.protobuf",
+			expectBody:        "k8s\u0000\n\u0017\n\u000Eautoscaling/v1\u0012\u0005Scale\u0012#\n\u0017\n\asnorlax\u0012\u0000\u001A\u0000\"\u0000*\u00002\u00008\u0000B\u0000\u0012\u0002\b\u0000\u001A\u0004\b\u0000\u0012\u0000\u001A\u0000\"\u0000",
+		},
+		{
+			name:              "json update scale",
+			createFunc:        updateScaleFunc,
+			contentType:       "application/json",
+			expectedPath:      "/apis/apps/v1/namespaces/panda/deployments/snorlax/scale",
+			expectContentType: "application/json",
+			expectBody: `{"kind":"Scale","apiVersion":"autoscaling/v1","metadata":{"name":"snorlax","creationTimestamp":null},"spec":{},"status":{"replicas":0}}
+`,
+		},
+		{
+			name:              "default via RESTClient",
+			createFunc:        createExampleViaRESTClientFunc,
+			contentType:       "",
+			expectedPath:      "/api/v1/namespaces/panda/examples",
+			expectContentType: "application/json",
+			expectBody: `{"metadata":{"name":"snorlax","creationTimestamp":null},"spec":{"foo":"","bar":false},"status":{}}
+`,
+		},
+		{
+			name:              "json via RESTClient",
+			createFunc:        createExampleViaRESTClientFunc,
+			contentType:       "application/json",
+			expectedPath:      "/api/v1/namespaces/panda/examples",
+			expectContentType: "application/json",
+			expectBody: `{"metadata":{"name":"snorlax","creationTimestamp":null},"spec":{"foo":"","bar":false},"status":{}}
+`,
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			var calls atomic.Uint64
+			ts := httptest.NewUnstartedServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+				calls.Add(1)
+
+				if got, want := r.URL.Path, tc.expectedPath; got != want {
+					t.Errorf("unexpected path, got=%q, want=%q", got, want)
+				}
+
+				if got, want := r.Header.Get("content-type"), tc.expectContentType; got != want {
+					t.Errorf("unexpected content-type, got=%q, want=%q", got, want)
+				}
+
+				if r.Body == nil {
+					t.Fatal("request body is nil")
+				}
+				body, err := io.ReadAll(r.Body)
+				if err != nil {
+					t.Fatal(err)
+				}
+				_ = r.Body.Close()
+				if diff := cmp.Diff(tc.expectBody, string(body)); len(diff) > 0 {
+					t.Errorf("body diff (-want, +got):\n%s", diff)
+				}
+
+				w.Header().Set("Content-Type", "application/json")
+				_, _ = w.Write([]byte("{}"))
+			}))
+			ts.Start()
+			defer ts.Close()
+
+			config := &rest.Config{
+				Host:          ts.URL,
+				ContentConfig: rest.ContentConfig{ContentType: tc.contentType},
+			}
+
+			tc.createFunc(t, config)
+
+			if calls.Load() != 1 {
+				t.Errorf("unexpected handler call count: %d", calls.Load())
+			}
+		})
+	}
+}