Istio Request Routing

$ export INGRESS_HOST=$(kubectl \
 --namespace istio-system \
 get service istio-ingressgateway \
 --output jsonpath="{.status.loadBalancer.ingress[0].ip}")

$ echo ${INGRESS_HOST}

$ cd ~/
$ git clone https://github.com/carnage-sh/cloud-for-fun/
$ cd cloud-for-fun/blog/istio-routing

$ kubectl apply -f helloworld-gateway-v1.yaml
$ kubectl apply -f helloworld-gateway-v2.yaml

$ cat << EOF | kubectl apply -f -
apiVersion: v1
kind: Service
metadata:
  name: helloworld-v1
  labels:
    app: helloworld
spec:
  ports:
  - port: 5000
    name: http
  selector:
    app: helloworld
    version: v1
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: helloworld-v1
  labels:
    version: v1
spec:
  replicas: 1
  selector:
    matchLabels:
      app: helloworld
  template:
    metadata:
      labels:
        app: helloworld
        version: v1
    spec:
      containers:
      - name: helloworld
        image: istio/examples-helloworld-v1
        resources:
          requests:
            cpu: "100m"
        imagePullPolicy: IfNotPresent #Always
        ports:
        - containerPort: 5000
EOF

$ cat << EOF | kubectl apply -f -
apiVersion: v1
kind: Service
metadata:
  name: helloworld-v2
  labels:
    app: helloworld
spec:
  ports:
  - port: 5000
    name: http
  selector:
    app: helloworld
    version: v2
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: helloworld-v2
  labels:
    version: v2
spec:
  replicas: 1
  selector:
    matchLabels:
      app: helloworld
  template:
    metadata:
      labels:
        app: helloworld
        version: v2
    spec:
      containers:
      - name: helloworld
        image: istio/examples-helloworld-v2
        resources:
          requests:
            cpu: "100m"
        imagePullPolicy: IfNotPresent #Always
        ports:
        - containerPort: 5000
EOF

$ kubectl get pods
NAME READY STATUS RESTARTS AGE
helloworld-v1-7476658d4f-vpqx9 1/1 Running 0 8m7s
helloworld-v2-786b58884c-g9vs5 1/1 Running 0 10s

$ curl $INGRESS_HOST
Hello version: v1, instance: helloworld-v1-7695cb4556-9dnsx

$ curl $INGRESS_HOST -H 'x-user: gregory'
Hello version: v2, instance: helloworld-v2-58b576ddf4-49zds

$ kubectl get vs
NAME         GATEWAYS               HOSTS   AGE
helloworld   [helloworld-gateway]   [*]     3m44s

$ kubectl get svc
NAME            TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)    AGE
helloworld-v1   ClusterIP   10.101.16.86     <none>        5000/TCP   6m10s
helloworld-v2   ClusterIP   10.110.180.253   <none>        5000/TCP   3m53s
kubernetes      ClusterIP   10.96.0.1        <none>        443/TCP    7m56s