UT: Increase unit test coverage of pkg/bootstrap (#101)

Signed-off-by: charlie <qianglin98@qq.com>

go.mod

@@ -16,6 +16,7 @@ replace github.com/docker/docker => github.com/moby/moby v17.12.0-ce-rc1.0.20200
 replace github.com/imdario/mergo => github.com/imdario/mergo v0.3.5
 
 require (
+	github.com/agiledragon/gomonkey/v2 v2.2.0
 	github.com/dubbogo/go-zookeeper v1.0.4-0.20211212162352-f9d2183d89d5
 	github.com/dubbogo/gost v1.13.1
 	github.com/envoyproxy/go-control-plane v0.10.2-0.20220325020618-49ff273808a1

go.sum

@@ -156,6 +156,8 @@ github.com/StackExchange/wmi v0.0.0-20190523213315-cbe66965904d/go.mod h1:3eOhrU
 github.com/VividCortex/ewma v1.1.1/go.mod h1:2Tkkvm3sRDVXaiyucHiACn4cqf7DpdyLvmxzcbUokwA=
 github.com/VividCortex/gohistogram v1.0.0/go.mod h1:Pf5mBqqDxYaXu3hDrrU+w6nw50o/4+TcAqDqk/vUH7g=
 github.com/afex/hystrix-go v0.0.0-20180502004556-fa1af6a1f4f5/go.mod h1:SkGFH1ia65gfNATL8TAiHDNxPzPdmEL5uirI2Uyuz6c=
+github.com/agiledragon/gomonkey/v2 v2.2.0 h1:QJWqpdEhGV/JJy70sZ/LDnhbSlMrqHAWHcNOjz1kyuI=
+github.com/agiledragon/gomonkey/v2 v2.2.0/go.mod h1:ap1AmDzcVOAz1YpeJ3TCzIgstoaWLA6jbbgxfB4w2iY=
 github.com/agnivade/levenshtein v1.0.1/go.mod h1:CURSv5d9Uaml+FovSIICkLbAUZ9S4RqaHDIsdSBg7lM=
 github.com/ahmetb/gen-crd-api-reference-docs v0.3.0/go.mod h1:TdjdkYhlOifCQWPs1UdTma97kQQMozf5h26hTuG70u8=
 github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=

pkg/bootstrap/server.go

@@ -229,7 +229,9 @@ func (s *Server) initConfigController() error {
 
 	// Defer starting the controller until after the service is created.
 	s.server.RunComponent(func(stop <-chan struct{}) error {
-		ingressConfig.InitializeCluster(ingressController, stop)
+		if err := ingressConfig.InitializeCluster(ingressController, stop); err != nil {
+			return err
+		}
 		go s.configController.Run(stop)
 		return nil
 	})
@@ -322,8 +324,7 @@ func (s *Server) initXdsServer() error {
 		s.xdsServer.Start(stop)
 		return nil
 	})
-	s.initGrpcServer()
-	return nil
+	return s.initGrpcServer()
 }
 
 func (s *Server) initGrpcServer() error {
@@ -381,6 +382,7 @@ func (s *Server) initHttpServer() error {
 	return nil
 }
 
+// readyHandler checks whether the http server is ready
 func (s *Server) readyHandler(w http.ResponseWriter, _ *http.Request) {
 	for name, fn := range s.readinessProbes {
 		if ready, err := fn(); !ready {
@@ -394,10 +396,7 @@ func (s *Server) readyHandler(w http.ResponseWriter, _ *http.Request) {
 
 // cachesSynced checks whether caches have been synced.
 func (s *Server) cachesSynced() bool {
-	if !s.configController.HasSynced() {
-		return false
-	}
-	return true
+	return s.configController.HasSynced()
 }
 
 func (s *Server) waitForCacheSync(stop <-chan struct{}) bool {

pkg/bootstrap/server_test.go

@@ -0,0 +1,66 @@
+// Copyright (c) 2022 Alibaba Group Holding Ltd.
+//
+// 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 bootstrap
+
+import (
+	"context"
+	"testing"
+
+	"github.com/agiledragon/gomonkey/v2"
+	"istio.io/istio/pilot/pkg/features"
+	"istio.io/istio/pkg/keepalive"
+
+	higresskube "github.com/alibaba/higress/pkg/kube"
+)
+
+func TestStartWithNoError(t *testing.T) {
+	var (
+		s   *Server
+		err error
+	)
+
+	mockFn := func(s *Server) error {
+		s.kubeClient = higresskube.NewFakeClient()
+		return nil
+	}
+
+	gomonkey.ApplyFunc((*Server).initKubeClient, mockFn)
+
+	if s, err = NewServer(newServerArgs()); err != nil {
+		t.Errorf("failed to create server: %v", err)
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	if err = s.Start(ctx.Done()); err != nil {
+		t.Errorf("failed to start the server: %v", err)
+	}
+}
+
+func newServerArgs() *ServerArgs {
+	return &ServerArgs{
+		Debug:                true,
+		NativeIstio:          true,
+		HttpAddress:          ":8888",
+		GrpcAddress:          ":15051",
+		GrpcKeepAliveOptions: keepalive.DefaultOption(),
+		XdsOptions: XdsOptions{
+			DebounceAfter:     features.DebounceAfter,
+			DebounceMax:       features.DebounceMax,
+			EnableEDSDebounce: features.EnableEDSDebounce,
+		},
+	}
+}

pkg/kube/client.go

@@ -61,6 +61,7 @@ func NewFakeClient(objects ...runtime.Object) Client {
 	}
 	c.higress = higressfake.NewSimpleClientset()
 	c.higressInformer = higressinformer.NewSharedInformerFactoryWithOptions(c.higress, resyncInterval)
+	c.informerWatchesPending = atomic.NewInt32(0)
 
 	// https://github.com/kubernetes/kubernetes/issues/95372
 	// There is a race condition in the client fakes, where events that happen between the List and Watch