Use client generator to generate all k8s clients and add respective client-go metrics (#2668)

* Define client generator to generate all k8s clients
* Increase QPS and burst values
* Capture client-go metrics
* Support for controller runtime metrics

Signed-off-by: Sanket Sudake <sanketsudake@gmail.com>

pkg/controller/api.go

@@ -68,8 +68,8 @@ type (
 	}
 )
 
-func MakeAPI(logger *zap.Logger) (*API, error) {
-	api, err := makeCRDBackedAPI(logger)
+func MakeAPI(logger *zap.Logger, fissionClient versioned.Interface, kubernetesClient kubernetes.Interface) (*API, error) {
+	api, err := makeCRDBackedAPI(logger, fissionClient, kubernetesClient)
 
 	u := os.Getenv("STORAGE_SERVICE_URL")
 	if len(u) > 0 {

pkg/controller/api_test.go

@@ -503,7 +503,8 @@ func TestMain(m *testing.M) {
 		return
 	}
 
-	_, kubeClient, _, _, err := crd.GetKubernetesClient()
+	clientGen := crd.NewClientGenerator()
+	kubeClient, err := clientGen.GetKubernetesClient()
 	panicIf(err)
 
 	// testNS isolation for running multiple CI builds concurrently.

pkg/controller/controller.go

@@ -27,9 +27,18 @@ import (
 func Start(ctx context.Context, logger *zap.Logger, port int, unitTestFlag bool) {
 	cLogger := logger.Named("controller")
 
-	fc, _, apiExtClient, _, err := crd.MakeFissionClient()
+	clientGen := crd.NewClientGenerator()
+	fissionClient, err := clientGen.GetFissionClient()
 	if err != nil {
-		cLogger.Fatal("failed to connect to k8s API", zap.Error(err))
+		cLogger.Fatal("failed to get fission client", zap.Error(err))
+	}
+	apiExtClient, err := clientGen.GetApiExtensionsClient()
+	if err != nil {
+		cLogger.Fatal("failed to get api extension client client", zap.Error(err))
+	}
+	kubeClient, err := clientGen.GetKubernetesClient()
+	if err != nil {
+		cLogger.Fatal("failed to get kubernetes client", zap.Error(err))
 	}
 
 	err = crd.EnsureFissionCRDs(ctx, cLogger, apiExtClient)
@@ -37,12 +46,12 @@ func Start(ctx context.Context, logger *zap.Logger, port int, unitTestFlag bool)
 		cLogger.Fatal("failed to find fission CRDs", zap.Error(err))
 	}
 
-	err = crd.WaitForCRDs(ctx, logger, fc)
+	err = crd.WaitForCRDs(ctx, logger, fissionClient)
 	if err != nil {
 		cLogger.Fatal("error waiting for CRDs", zap.Error(err))
 	}
 
-	api, err := MakeAPI(cLogger)
+	api, err := MakeAPI(cLogger, fissionClient, kubeClient)
 	if err != nil {
 		cLogger.Fatal("failed to start controller", zap.Error(err))
 	}

pkg/controller/crd.go

@@ -18,15 +18,12 @@ package controller
 
 import (
 	"go.uber.org/zap"
+	"k8s.io/client-go/kubernetes"
 
-	"github.com/fission/fission/pkg/crd"
+	"github.com/fission/fission/pkg/generated/clientset/versioned"
 )
 
-func makeCRDBackedAPI(logger *zap.Logger) (*API, error) {
-	fissionClient, kubernetesClient, _, _, err := crd.MakeFissionClient()
-	if err != nil {
-		return nil, err
-	}
+func makeCRDBackedAPI(logger *zap.Logger, fissionClient versioned.Interface, kubernetesClient kubernetes.Interface) (*API, error) {
 	return &API{
 		logger:           logger.Named("api"),
 		fissionClient:    fissionClient,