add unit test for CheckEndpointState method

Signed-off-by: Fabian Lopez <lfabian@vmware.com>

test/spoof_test.go

@@ -0,0 +1,150 @@
+/*
+Copyright 2021 The Knative 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.
+*/
+
+// spoof contains logic to make polling HTTP requests against an endpoint with optional host spoofing.
+
+package test
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"net/url"
+	"testing"
+
+	corev1 "k8s.io/api/core/v1"
+	v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"knative.dev/pkg/client/injection/kube/client/fake"
+	"knative.dev/pkg/test/spoof"
+)
+
+type fakeTransport struct{}
+
+func (ft *fakeTransport) RoundTrip(req *http.Request) (*http.Response, error) {
+	return &http.Response{
+		Status:     "200 ok",
+		StatusCode: 200,
+		Header:     http.Header{},
+		Body:       http.NoBody,
+	}, nil
+}
+
+type countCalls struct {
+	calls int32
+}
+
+func (c *countCalls) count(rc spoof.ResponseChecker) spoof.ResponseChecker {
+	return func(resp *spoof.Response) (done bool, err error) {
+		c.calls++
+		return rc(resp)
+	}
+}
+
+func TestSpoofingClient_CheckEndpointState(t *testing.T) {
+	ingress := &corev1.Service{
+		ObjectMeta: v1.ObjectMeta{
+			Name:      "istio-ingressgateway",
+			Namespace: "istio-system",
+		},
+		Status: corev1.ServiceStatus{
+			LoadBalancer: corev1.LoadBalancerStatus{
+				Ingress: []corev1.LoadBalancerIngress{
+					{
+						Hostname: "host",
+					},
+				},
+			},
+		},
+	}
+	type args struct {
+		url     *url.URL
+		inState spoof.ResponseChecker
+		desc    string
+		opts    []RequestOption
+	}
+	tests := []struct {
+		name      string
+		args      args
+		wantErr   bool
+		wantCalls int32
+	}{{
+		name: "Non matching response doesn't trigger a second check",
+		args: args{
+			url: &url.URL{
+				Host:   "fake.knative.net",
+				Scheme: "http",
+			},
+			inState: func(resp *spoof.Response) (done bool, err error) {
+				return false, nil
+			},
+		},
+		wantErr:   false,
+		wantCalls: 1,
+	}, {
+		name: "Error response doesn't trigger a second check",
+		args: args{
+			url: &url.URL{
+				Host:   "fake.knative.net",
+				Scheme: "http",
+			},
+			inState: func(resp *spoof.Response) (done bool, err error) {
+				return false, fmt.Errorf("response error")
+			},
+		},
+		wantErr:   true,
+		wantCalls: 1,
+	}, {
+		name: "OK response doesn't trigger a second check",
+		args: args{
+			url: &url.URL{
+				Host:   "fake.knative.net",
+				Scheme: "http",
+			},
+			inState: func(resp *spoof.Response) (done bool, err error) {
+				return true, nil
+			},
+		},
+		wantErr:   false,
+		wantCalls: 1,
+	}}
+	for _, tt := range tests {
+		_, fKlient := fake.With(context.TODO(), ingress)
+		t.Run(tt.name, func(t *testing.T) {
+			sc, err := NewSpoofingClient(
+				context.TODO(),
+				fKlient,
+				t.Logf,
+				"some.svc.knative.dev",
+				false,
+			)
+			if err != nil {
+				t.Fatalf("Spoofing client not created: %v", err)
+			}
+			sc.Client = &http.Client{
+				Transport: &fakeTransport{},
+			}
+			counter := countCalls{}
+			_, err = sc.CheckEndpointState(context.TODO(), tt.args.url, counter.count(tt.args.inState), tt.args.desc, tt.args.opts...)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("SpoofingClient.CheckEndpointState() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if counter.calls != tt.wantCalls {
+				t.Errorf("Expected ResponseChecker to be invoked %d time but got invoked %d", tt.wantCalls, counter.calls)
+			}
+		})
+	}
+}