Request Routing

This task shows you how to set up Request Routing policy for http traffic in Kmesh.

Before you begin

• Install Kmesh

  Please refer quickstart and change into ads mode

• Deploy the fortio Applications

kubectl apply -f samples/fortio/fortio-route.yaml
kubectl apply -f samples/fortio/netutils.yaml

• Check app status and ensure that the service application is managed by Kmesh

  kubectl get pod 
  NAME                         READY   STATUS    RESTARTS   AGE
  fortio-v1-596b55cb8b-sfktr   1/1     Running   0          57m
  fortio-v2-76997f99f4-qjsmd   1/1     Running   0          57m
  netutils-575f5c569-lr98z     1/1     Running   0          67m
  
  kubectl describe pod netutils-575f5c569-lr98z | grep Annotations
  Annotations:      kmesh.net/redirection: enabled
  

Test the routing configuration

• Display the defined routes with the following command:

  $ kubectl get virtualservices -o yaml
  apiVersion: v1
  items:
  - apiVersion: networking.istio.io/v1beta1
    kind: VirtualService
    metadata:
      annotations:
        kubectl.kubernetes.io/last-applied-configuration: |
          {"apiVersion":"networking.istio.io/v1alpha3","kind":"VirtualService","metadata":{"annotations":{},"name":"fortio","namespace":"default"},"spec":{"hosts":["fortio"],"http":[{"route":[{"destination":{"host":"fortio","subset":"v1"},"weight":90},{"destination":{"host":"fortio","subset":"v2"},"weight":10}]}]}}
      creationTimestamp: "2024-07-09T09:00:36Z"
      generation: 1
      name: fortio
      namespace: default
      resourceVersion: "11166"
      uid: 0a07f283-ac26-4d86-b3bd-ce6aa07dc628
    spec:
      hosts:
      - fortio
      http:
      - route:
        - destination:
            host: fortio
            subset: v1
          weight: 90
        - destination:
            host: fortio
            subset: v2
          weight: 10
  kind: List
  metadata:
    resourceVersion: ""
  

• You have configured fortio 90% to route to the v1 version of the fortio server

  $ for i in {1..20}; do kubectl exec -it $(kubectl get pod | grep netutils | awk '{print $1}') -- curl -v $(kubectl get svc -owide | grep fortio | awk '{print $3}'):80 | grep "Server:"; done
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 2
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 2
  < Server: 1
  < Server: 1
  

Route based on user identity

• Next, you will change the route configuration so that all traffic from a specific user is routed to a specific service version. In this case, all traffic from a user named Jason will be routed to the service fortio:v2.

• kubectl apply -f samples/fortio/fortio-header.yaml

  fortio-header.yaml

  apiVersion: networking.istio.io/v1alpha3
  kind: VirtualService
  metadata:
    name: fortio
  spec:
    hosts:
    - fortio
    http:
    - match:
      - headers:
          end-user:
            exact: jason
      route:
      - destination:
          host: fortio
          subset: v2
    - route:
      - destination:
          host: fortio
          subset: v1
  

• Verify response from Server 1

  [root@localhost route]# for i in {1..10}; do kubectl exec -it $(kubectl get pod | grep netutils | awk '{print $1}') -- curl -v $(kubectl get svc -owide | grep fortio | awk '{print $3}'):80 | grep "Server:"; done
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 1
  < Server: 1
  

• Verify response from Server 2 with header

  [root@localhost route]# for i in {1..10}; do kubectl exec -it $(kubectl get pod | grep netutils | awk '{print $1}') -- curl \--header "end-user:jason" -v $(kubectl get svc -owide | grep fortio | awk '{print $3}'):80 | grep "Server:"; done
  < Server: 2
  < Server: 2
  < Server: 2
  < Server: 2
  < Server: 2
  < Server: 2
  < Server: 2
  < Server: 2
  < Server: 2
  < Server: 2
  

Understanding what happened

If the user request header is not configured, V1 will be used. If the Jason request header is configured, V2 will be used.

Clean up

1. Remove the application route rules

kubectl delete -f samples/fortio/fortio-route.yaml
kubectl delete -f samples/fortio/netutils.yaml

2. Remove kmesh

   Please refer cleanup