Use a separate controller loop to watch functions change and create a service (#544)

2018-04-04 01:17:51 +08:00
parent d39944e04d
commit 2a06705320
13 changed files with 186 additions and 108 deletions
@@ -0,0 +1,125 @@
+/*
+Copyright 2018 The Fission 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 poolmgr
+
+import (
+	"time"
+
+	log "github.com/sirupsen/logrus"
+	kerrors "k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/fields"
+	"k8s.io/apimachinery/pkg/util/intstr"
+	"k8s.io/client-go/kubernetes"
+	apiv1 "k8s.io/client-go/pkg/api/v1"
+	"k8s.io/client-go/rest"
+	k8sCache "k8s.io/client-go/tools/cache"
+
+	"github.com/fission/fission"
+	"github.com/fission/fission/crd"
+)
+
+func getIstioServiceLabels(fnName string) map[string]string {
+	return map[string]string{
+		"functionName": fnName,
+	}
+}
+
+func makeFuncIstioServiceRegister(crdClient *rest.RESTClient,
+	kubernetesClient *kubernetes.Clientset, fnNamespace string) k8sCache.Controller {
+
+	resyncPeriod := 30 * time.Second
+	lw := k8sCache.NewListWatchFromClient(crdClient, "functions", metav1.NamespaceDefault, fields.Everything())
+	_, controller := k8sCache.NewInformer(lw, &crd.Function{}, resyncPeriod,
+		k8sCache.ResourceEventHandlerFuncs{
+			AddFunc: func(obj interface{}) {
+
+				fn := obj.(*crd.Function)
+
+				// Since istio only allows accessing pod through k8s service,
+				// for the functions with executor type "poolmgr" we need to
+				// create a service for sending requests to pod in pool.
+				// Functions with executor type "Newdeploy" is specialized at
+				// pod starts. In this case, just ignore such functions.
+				fnExecutorType := fn.Spec.InvokeStrategy.ExecutionStrategy.ExecutorType
+				if fnExecutorType != fission.ExecutorTypePoolmgr {
+					return
+				}
+
+				// create a same name service for function
+				// since istio only allows the traffic to service
+				sel := map[string]string{
+					"functionName": fn.Metadata.Name,
+					"functionUid":  string(fn.Metadata.UID),
+				}
+
+				svcName := fission.GetFunctionIstioServiceName(fn.Metadata.Name, fn.Metadata.Namespace)
+
+				// service for accepting user traffic
+				svc := apiv1.Service{
+					ObjectMeta: metav1.ObjectMeta{
+						Namespace: fnNamespace,
+						Name:      svcName,
+						Labels:    getIstioServiceLabels(fn.Metadata.Name),
+					},
+					Spec: apiv1.ServiceSpec{
+						Type: apiv1.ServiceTypeClusterIP,
+						Ports: []apiv1.ServicePort{
+							// Service port name should begin with a recognized prefix, or the traffic will be
+							// treated as TCP traffic. (https://istio.io/docs/setup/kubernetes/sidecar-injection.html)
+							// Originally the ports' name are similar to "http-fetch" and "http-specialize".
+							// But for istio 0.5.1, istio-proxy return unexpected 431 error with such naming.
+							// https://github.com/istio/istio/issues/928
+							// Workaround: remove prefix
+							// TODO: prepend prefix once the bug fixed
+							{
+								Name:       "fetch",
+								Protocol:   apiv1.ProtocolTCP,
+								Port:       8000,
+								TargetPort: intstr.FromInt(8000),
+							},
+							{
+								Name:       "specialize",
+								Protocol:   apiv1.ProtocolTCP,
+								Port:       8888,
+								TargetPort: intstr.FromInt(8888),
+							},
+						},
+						Selector: sel,
+					},
+				}
+
+				// create function istio service if it does not exist
+				_, err := kubernetesClient.CoreV1().Services(fnNamespace).Create(&svc)
+				if err != nil && !kerrors.IsAlreadyExists(err) {
+					log.Printf("Error creating function istio service: %v", err)
+				}
+			},
+			DeleteFunc: func(obj interface{}) {
+				fn := obj.(*crd.Function)
+				svcName := fission.GetFunctionIstioServiceName(fn.Metadata.Name, fn.Metadata.Namespace)
+				// delete function istio service
+				err := kubernetesClient.CoreV1().Services(fnNamespace).Delete(svcName, nil)
+				if err != nil && !kerrors.IsNotFound(err) {
+					log.Printf("Error deleting function istio service: %v", err)
+				}
+			},
+			UpdateFunc: func(oldObj, newObj interface{}) {},
+		})
+
+	return controller
+}