Add function in payload instead of just metadata (#1919)

Passing information of function from router to executor is more efficient than calling the K8S API. This change does that instead of passing only metadata and then executor calling the K8S API again.

pkg/executor/api.go

@@ -28,8 +28,6 @@ import (
 	"github.com/pkg/errors"
 	"go.opencensus.io/plugin/ochttp"
 	"go.uber.org/zap"
-	k8serrors "k8s.io/apimachinery/pkg/api/errors"
-	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 
 	fv1 "github.com/fission/fission/pkg/apis/core/v1"
 	ferror "github.com/fission/fission/pkg/error"
@@ -44,23 +42,13 @@ func (executor *Executor) getServiceForFunctionAPI(w http.ResponseWriter, r *htt
 	}
 
 	// get function metadata
-	m := metav1.ObjectMeta{}
-	err = json.Unmarshal(body, &m)
+	fn := &fv1.Function{}
+	err = json.Unmarshal(body, &fn)
 	if err != nil {
 		http.Error(w, "Failed to parse request", http.StatusBadRequest)
 		return
 	}
 
-	fn, err := executor.fissionClient.CoreV1().Functions(m.Namespace).Get(m.Name, metav1.GetOptions{})
-	if err != nil {
-		if k8serrors.IsNotFound(err) {
-			http.Error(w, "Failed to find function", http.StatusNotFound)
-		} else {
-			http.Error(w, "Failed to get function", http.StatusInternalServerError)
-		}
-		return
-	}
-
 	t := fn.Spec.InvokeStrategy.ExecutionStrategy.ExecutorType
 	et, exists := executor.executorTypes[t]
 	if !exists {
@@ -88,7 +76,7 @@ func (executor *Executor) getServiceForFunctionAPI(w http.ResponseWriter, r *htt
 		code, msg := ferror.GetHTTPError(err)
 		executor.logger.Error("error getting service for function",
 			zap.Error(err),
-			zap.String("function", m.Name),
+			zap.String("function", fn.ObjectMeta.Name),
 			zap.String("fission_http_error", msg))
 		http.Error(w, msg, code)
 		return
@@ -98,7 +86,7 @@ func (executor *Executor) getServiceForFunctionAPI(w http.ResponseWriter, r *htt
 	if err != nil {
 		executor.logger.Error(
 			"error writing HTTP response",
-			zap.String("function", m.Name),
+			zap.String("function", fn.ObjectMeta.Name),
 			zap.Error(err),
 		)
 	}

pkg/executor/client/client.go

@@ -70,10 +70,10 @@ func MakeClient(logger *zap.Logger, executorURL string) *Client {
 }
 
 // GetServiceForFunction returns the service name for a given function.
-func (c *Client) GetServiceForFunction(ctx context.Context, metadata *metav1.ObjectMeta) (string, error) {
+func (c *Client) GetServiceForFunction(ctx context.Context, fn *fv1.Function) (string, error) {
 	executorURL := c.executorURL + "/v2/getServiceForFunction"
 
-	body, err := json.Marshal(metadata)
+	body, err := json.Marshal(fn)
 	if err != nil {
 		return "", errors.Wrap(err, "could not marshal request body for getting service for function")
 	}

pkg/executor/executor_test.go

@@ -256,7 +256,7 @@ func TestExecutor(t *testing.T) {
 
 	// the main test: get a service for a given function
 	t1 := time.Now()
-	svc, err := poolmgrClient.GetServiceForFunction(context.Background(), &f.ObjectMeta)
+	svc, err := poolmgrClient.GetServiceForFunction(context.Background(), f)
 	if err != nil {
 		log.Panicf("failed to get func svc: %v", err)
 	}

pkg/router/functionHandler.go

@@ -528,7 +528,7 @@ func (fh functionHandler) getServiceEntryFromExecutor() (*url.URL, error) {
 
 	ctx, cancel := context.WithTimeout(context.Background(), timeout)
 	defer cancel()
-	service, err := fh.executor.GetServiceForFunction(ctx, &fh.function.ObjectMeta)
+	service, err := fh.executor.GetServiceForFunction(ctx, fh.function)
 	if err != nil {
 		statusCode, errMsg := ferror.GetHTTPError(err)
 		fh.logger.Error("error from GetServiceForFunction",