Istio 例子(单个应用，灰度发布)

准备工作

安装好 Istio

# 安装 demo 配置
istioctl install --set profile=demo

# 设置启用自动注入 istio sidecar 的命名空间
kubectl label namespace default istio-injection=enabled


# 获取 nodePort 地址 
export INGRESS_PORT=$(kubectl -n istio-system get service istio-ingressgateway -o jsonpath='{.spec.ports[?(@.name=="http2")].nodePort}')
export SECURE_INGRESS_PORT=$(kubectl -n istio-system get service istio-ingressgateway -o jsonpath='{.spec.ports[?(@.name=="https")].nodePort}')
export INGRESS_HOST=$(kubectl get po -l istio=ingressgateway -n istio-system -o jsonpath='{.items[0].status.hostIP}')
export GATEWAY_URL=$INGRESS_HOST:$INGRESS_PORT

echo "$GATEWAY_URL"

创建单个应用

vi myapp-demo.yaml 

apiVersion: v1
kind: Service
metadata:
  name: myapp-svc
  labels:
    app: myapp
spec:
  ports:
  - port: 80
    name: http
  selector:
    app: myapp-pod
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp-v1
  labels:
    app: myapp-pod
    version: v1
spec:
  replicas: 1
  selector:
    matchLabels:
      app: myapp-pod
      version: v1
  template:
    metadata:
      labels:
        app: myapp-pod
        version: v1
    spec:
      containers:
      - name: myapp-pod
        image: ikubernetes/myapp:v1
        ports:
        - containerPort: 80

kubectl apply -f myapp-demo.yaml

# 检查应用是否正确启用
kubectl get pod,svc 

# 创建 Gateway 和 VirtualService
vi gateway.yaml 
apiVersion: networking.istio.io/v1alpha3
kind: Gateway
metadata:
  name: myapp-gateway
spec:
  selector:
    istio: ingressgateway # use istio default controller
  servers:
  - port:
      number: 80
      name: http
      protocol: HTTP
    hosts:
    - "*"
---
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: myapp-vs
spec:
  hosts:
  - "*"
  gateways:
  - myapp-gateway
  http:
  - match:
    - uri:
        prefix: /
    route:
    - destination:
        host: myapp-svc.default.svc.cluster.local    # 指定 K8S 中的 svc 资源名字
        port:
          number: 80

# 启动 
kubectl apply -f gateway.yaml 

# 因为我的 nodeip 为 172.18.34.35:32151，所以使用浏览器访问

创建两个应用，灰度发布(流量比例9:1)

# 清理上面的资源 
kubectl delete -f gateway.yaml
kubectl delete -f myapp-demo.yaml

# 创建两个 pod 和 svc

vi myapp-demo2.yaml

apiVersion: v1
kind: Service
metadata:
  name: myapp-svc
spec:
  ports:
  - port: 80
    name: http
  selector:
    app: myapp-pod
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp-v1
  labels:
    app: myapp-pod
    version: v1
spec:
  replicas: 1
  selector:
    matchLabels:
      app: myapp-pod
      version: v1
  template:
    metadata:
      labels:
        app: myapp-pod
        version: v1
    spec:
      containers:
      - name: myapp-pod
        image: ikubernetes/myapp:v1
        ports:
        - containerPort: 80
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp-v2
  labels:
    app: myapp-pod
    version: v2
spec:
  replicas: 1
  selector:
    matchLabels:
      app: myapp-pod
      version: v2
  template:
    metadata:
      labels:
        app: myapp-pod
        version: v2
    spec:
      containers:
      - name: myapp-pod
        image: ikubernetes/myapp:v2
        ports:
        - containerPort: 80

kubectl apply -f myapp-demo2.yaml

# 检查应用是否正确启用
kubectl get pod,svc 

# 创建 Gateway, VirtualService 和 DestinationRule
vi gateway2.yaml 

apiVersion: networking.istio.io/v1alpha3
kind: Gateway
metadata:
  name: myapp-gateway
spec:
  selector:
    istio: ingressgateway # use istio default controller
  servers:
  - port:
      number: 80
      name: http
      protocol: HTTP
    hosts:
    - "*"
---
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: myapp-vs
spec:
  hosts:
  - "*"
  gateways:
  - myapp-gateway
  http:
  - route:
    - destination:
        host: myapp-svc.default.svc.cluster.local      # 指定 K8S 中的 svc 资源名字
        subset: v1
        port:
          number: 80
      weight: 90
    - destination:
        host: myapp-svc.default.svc.cluster.local      # 指定 K8S 中的 svc 资源名字
        subset: v2
        port:
          number: 80
      weight: 10
---
apiVersion: networking.istio.io/v1beta1
kind: DestinationRule
metadata:
  name: myapp-dr
  namespace: default
spec:
  host: myapp-svc.default.svc.cluster.local            # 指定 K8S 中的 svc 资源名字
  subsets:
  - labels:
      version: v1
    name: v1
  - labels:
      version: v2
    name: v2

kubectl apply -f gateway2.yaml 

v1版本和v2版本的比例为9:1