Replace Ingress/RouteRule in sample/knative-routing with VirtualService (#61)

* Replace Ingress/RouteRule in sample/knative-routing with VirtualService

* fix typos and update the graph

* fix typos

serving/samples/knative-routing/README.md

@@ -1,16 +1,17 @@
 # Routing across Knative Services
 
 This example shows how to map multiple Knative services to different paths 
-under a single domain name using the Istio Ingress and RouteRule concepts. 
+under a single domain name using the Istio VirtualService concept. 
 Since Istio is a general-purpose reverse proxy, these directions can also be 
 used to configure routing based on other request data such as headers, or even 
 to map Knative and external resources under the same domain name.
 
 In this sample, we set up two web services: "Search" service and "Login" 
 service, which simply read in an env variable 'SERVICE_NAME' and prints 
-"${SERVICE_NAME} is called". We'll then create an Ingress with host 
+"${SERVICE_NAME} is called". We'll then create a VirtualService with host 
-"example.com", and routing rules so that example.com/search maps to the Search 
+"example.com", and define routing rules in the VirtualService so that 
-service, and example.com/login maps to the Login service.
+"example.com/search" maps to the Search service, and "example.com/login" maps 
+to the Login service.
 
 ## Prerequisites
 
@@ -43,99 +44,93 @@ kubectl apply -f sample/knative-routing/sample.yaml
 ```
 
 ## Exploring
-Once deployed, you can inspect Knative services with
-```shell
-kubectl get service.knative.dev
-```
-You should see 2 Knative services: Search and Login.
-And you can inspect the corresponding Ingress with
-```shell
-kubectl get Ingress
-```
-You should see 2 Ingress objects:
 
+A shared Gateway "knative-shared-gateway" is used within Knative service mesh 
+for serving all incoming traffic. You can inspect it and its corresponding k8s 
+service with
+```shell
+# Check shared Gateway
+kubectl get Gateway -n knative-serving -oyaml
+
+# Check the corresponding k8s service for the shared gateway
+kubectl get svc knative-ingressgateway -n istio-system -oyaml
 ```
-NAME                                 HOSTS                                                                                         ADDRESS        PORTS
+
-login-service-ela-ingress     login-service.default.example.com,*.login-service.default.example.com    35.237.65.249      80
+And you can inspect the deployed Knative services with
-search-service-ela-ingress    search-service.default.example.com,*.search-service.default.example.com   35.237.65.249      80
+```shell
+kubectl get service.serving.knative.dev
 ```
-The login-service-ela-ingress and search-service-ela-ingress are Ingresses corresponding to "Login" service and "Search" service.
+You should see 2 Knative services: search-service and login-service.
 
 You can directly access "Search" service by running
 ```shell
-curl http://35.237.65.249 --header "Host:search-service.default.example.com"
+# Get the ingress IP.
+export GATEWAY_IP=`kubectl get svc knative-ingressgateway -n istio-system -o jsonpath="{.status.loadBalancer.ingress[*]['ip']}"`
+
+export SERVICE_HOST=`kubectl get route search-service -o jsonpath="{.status.domain}"`
+
+curl http://${GATEWAY_IP} --header "Host:${SERVICE_HOST}"
 ```
 You should see
 ```
 Search Service is called !
 ```
-Similarly, you can also directly access "Login" service.
+Similarly, you can also directly access "Login" service with
+```shell
+# Get the ingress IP.
+export GATEWAY_IP=`kubectl get svc knative-ingressgateway -n istio-system -o jsonpath="{.status.loadBalancer.ingress[*]['ip']}"`
+
+export SERVICE_HOST=`kubectl get route login-service -o jsonpath="{.status.domain}"`
+
+curl http://${GATEWAY_IP} --header "Host:${SERVICE_HOST}"
+```
+You should see
+```
+Login Service is called !
+```
 
 ## Apply Custom Routing Rule
-You can apply the custom routing rule defined in "routing.yaml" file with
+
+You can apply the custom routing rules defined in "routing.yaml" file with
 ```shell
 kubectl apply -f sample/knative-routing/routing.yaml
 ```
-The routing.yaml file will generate a new Ingress "entry-ingress" for domain 
+The routing.yaml file will generate a new VirtualService "entry-route" for 
-"example.com". You can see it by running
+domain "example.com". You can see it by running
 ```shell
-kubectl get Ingress
+kubectl get VirtualService entry-route -o yaml
-```
-And you should see "entry-ingress" is added into the Ingress results:
-```
-NAME            HOSTS         ADDRESS         PORTS     AGE
-entry-ingress   example.com   35.237.65.249   80        4h
 ```
+
 Now you can send request to "Search" service and "Login" service by using 
 different URI.
 
 ```shell
+# Get the ingress IP.
+export GATEWAY_IP=`kubectl get svc knative-ingressgateway -n istio-system -o jsonpath="{.status.loadBalancer.ingress[*]['ip']}"`
+
 # send request to Search service
-curl http://35.237.65.249/search --header "Host:example.com"
+curl http://${GATEWAY_IP}/search --header "Host:example.com"
 
 # send request to Login service
-curl http://35.237.65.249/login --header "Host:example.com"
+curl http://${GATEWAY_IP}/login --header "Host:example.com"
 ```
 You should get the same results as you directly access these services.
 
-## Exploring Custom Routing Rule
-Besides "entry-ingress" Ingress, there are another 3 objects that are 
-generated: 
-"entry-service" Service, "entry-route-search" RouteRule and 
-"entry-route-login" RouteRule.
-
-You can inspect the details of each objects by running:
-```shell
-# Check details of entry-service Service:
-kubectl get Service entry-service -o yaml
-
-# Check details of entry-route-search RouteRule
-kubectl get RouteRule entry-route-search -o yaml
-
-# Check details of entry-route-login RouteRule
-kubectl get RouteRule entry-route-login -o yaml
-```
 
 ## How It Works
+
 This is the traffic flow of this sample:
 ![Object model](images/knative-routing-sample-flow.png)
 
-4 components are defined in order to implement the routing.
-1. Ingress "entry-ingress": a new Ingress entry for routing traffic.
-2. Service "entry-service": a placeholder service needed for setting up Ingress and RouteRule
-3. RouteRule "entry-route-search": a RouteRule that checks if request has URI "
-/search", and forwards the request to "Search" service.
-4. RouteRule "entry-route-login": a RouteRule that checks if request has URI "
-/login", and forwards the request to "Login" service.
 
-When an external request reaches "entry-ingress" Ingress, the Ingress proxy 
+When an external request with host "example.com" reaches 
-will check if it has "/search" or "/login" URI. If it has, then the host of 
+"knative-shared-gateway" Gateway, the "entry-route" VirtualService will check 
+if it has "/search" or "/login" URI. If it has, then the host of 
 request will be rewritten into the host of "Search" service or "Login" service 
 correspondingly, which actually resets the final destination of the request. 
-The host rewriting is defined in RouteRule ""entry-route-search" and "entry-route-login".
+The request with updated host will be forwarded to "knative-shared-gateway" 
-The request with updated host will be forwarded to Ingress proxy again. The 
+Gateway again. The Gateway proxy checks the updated host, and forwards it to 
-Ingress proxy checks the updated host, and forwards it to "Search" or "Login" 
+"Search" or "Login" service according to its host setting.
-service according to its host setting.
 
 ## Cleaning up
 

serving/samples/knative-routing/routing.yaml

@@ -1,93 +1,57 @@
-# This is the Ingress exposed as the entry of service mesh defined by user with custom routing rules.
+# Copyright 2018 The Knative Authors
-apiVersion: extensions/v1beta1
+#
-kind: Ingress
+# 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
+#
+#     https://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.
+
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
 metadata:
-  annotations:
+  name: entry-route
-    kubernetes.io/ingress.class: istio
-  name: entry-ingress
   namespace: default
 spec:
-  rules:
+  # This is the gateway shared in knative service mesh.
+  gateways:
+  - knative-shared-gateway.knative-serving.svc.cluster.local
   # Set host to the domain name that you own.
-  - host: example.com
+  hosts:
+  - example.com
   http:
-      paths:
+  - match:
-      - backend:
+    - uri:
-          serviceName: entry-service
-          servicePort: http
----
-# This is the placeholder service that backs up the entry Ingress.
-# User does not need to change this component.
-apiVersion: v1
-kind: Service
-metadata:
-  name: entry-service
-  namespace: default
-spec:
-  ports:
-  - name: http
-    port: 80
-    protocol: TCP
-    targetPort: 80
-  sessionAffinity: None
-  type: ClusterIP
----
-# This is an example of routing rule that redirects requests with URI "/search" prefix
-# to Knative Search service.
-apiVersion: config.istio.io/v1alpha2
-kind: RouteRule
-metadata:
-  name: entry-route-search
-  namespace: default
-spec:
-  destination:
-    name: entry-service
-    namespace: default
-  # Define the rule matching request header with "/search" prefix.
-  match:
-    request:
-      headers:
-        uri:
         prefix: "/search"
     rewrite:
       # Rewrite the original host header to the host header of Search service
       # in order to redirect requests to Search service.
       authority: search-service.default.example.com
     route:
+      # knative-ingressgateway is the k8s service created by Knative as the 
+      # shared gateway of all traffic incoming to the cluster.
+      # Basically here we redirect the request to the cluster entry again with 
+      # updated header "search-service.default.example.com" so the request will 
+      # eventually be directed to Search service.
       - destination:
-      # istio-ingress is the k8s service created by Istio as the actual entry of all traffic incoming to the cluster.
+          host: knative-ingressgateway.istio-system.svc.cluster.local
-      # Basically here we redirect the request to the cluster entry again with updated header
-      # "search-service.default.example.com" so the request will eventually be directed to Search service.
-      name: istio-ingress
-      namespace: istio-system
         weight: 100
----
+  - match:
-# This is an example of routing rule that redirects requests with URI "/login" prefix
+    - uri:
-# to Knative Login service.
-apiVersion: config.istio.io/v1alpha2
-kind: RouteRule
-metadata:
-  name: entry-route-login
-  namespace: default
-spec:
-  destination:
-    name: entry-service
-    namespace: default
-  # Define the rule matching request header with "/login" prefix.
-  match:
-    request:
-      headers:
-        uri:
         prefix: "/login"
     rewrite:
-    # Rewrite the original host header to the host header of Login service
+      # Rewrite the original host header to the host header of Search service
-    # in order to redirect requests to Login service.
+      # in order to redirect requests to Search service.
       authority: login-service.default.example.com
     route:
-    # istio-ingress is the k8s service created by Istio as the actual entry of all traffic incoming to the cluster.
+      # Basically here we redirect the request to the cluster entry again with 
-    # Basically here we redirect the request to the cluster entry again with updated header
+      # updated header "login-service.default.example.com" so the request will 
-    # "login-service.default.example.com" so the request will eventually be directed to Login service. 
+      # eventually be directed to LOgin service.
       - destination:
-      name: istio-ingress
+          host: knative-ingressgateway.istio-system.svc.cluster.local
-      namespace: istio-system
         weight: 100