Use nginx ingress to implement grayscale deployment in kubernetes

Overview

1) kuberntes cluster environment: v1.14.2.
2) nginx ingress version: nginx-ingress-controller: 0.25.0.
3) nginx ingress deployment method: daemonset, and directly use the host network (ie host mode), port 80.
4) Official document address: https://kubernetes.github.io/ingress-nginx/user-guide/nginx-configuration/annotations/#canary

1) Gray release based on weight (30% of requests flow into the canary service)

1) Step 1: Deploy production and canary services

[root@master canary]# cat production.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: production
  labels:
    app: production
spec:
  replicas: 1
  selector:
    matchLabels:
      app: production
  template:
    metadata:
      labels:
        app: production
    spec:
      containers:
      - name: production
        image: registry.aliyuncs.com/google_containers/echoserver:1.10
        ports:
        - containerPort: 8080
        env:
          - name: NODE_NAME
            valueFrom:
              fieldRef:
                fieldPath: spec.nodeName
          - name: POD_NAME
            valueFrom:
              fieldRef:
                fieldPath: metadata.name
          - name: POD_NAMESPACE
            valueFrom:
              fieldRef:
                fieldPath: metadata.namespace
          - name: POD_IP
            valueFrom:
              fieldRef:
                fieldPath: status.podIP
---
apiVersion: v1
kind: Service
metadata:
  name: production
  labels:
    app: production
spec:
  ports:
  - port: 80
    targetPort: 8080
    protocol: TCP
    name: http
  selector:
    app: production


[root@master canary]# cat canary.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: canary
  labels:
    app: canary
spec:
  replicas: 1
  selector:
    matchLabels:
      app: canary
  template:
    metadata:
      labels:
        app: canary
    spec:
      containers:
      - name: canary
        image: registry.aliyuncs.com/google_containers/echoserver:1.10
        ports:
        - containerPort: 8080
        env:
          - name: NODE_NAME
            valueFrom:
              fieldRef:
                fieldPath: spec.nodeName
          - name: POD_NAME
            valueFrom:
              fieldRef:
                fieldPath: metadata.name
          - name: POD_NAMESPACE
            valueFrom:
              fieldRef:
                fieldPath: metadata.namespace
          - name: POD_IP
            valueFrom:
              fieldRef:
                fieldPath: status.podIP
---
apiVersion: v1
kind: Service
metadata:
  name: canary
  labels:
    app: canary
spec:
  ports:
  - port: 80
    targetPort: 8080
    protocol: TCP
    name: http
  selector:
    app: canary

2) Visit product and canary services to check whether the service is running normally

3) Deploy ingress corresponding to production and canary services

[root@master canary]# cat production-ingress.yaml
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: production
  annotations:
    kubernetes.io/ingress.class: nginx
spec:
  rules:
  - host: master.example.com
    http:
      paths:
      - backend:
          serviceName: production
          servicePort: 80
        path: /apis/echo

[root@master canary]# cat canary-weight-ingress.yaml
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: canary
  annotations:
    kubernetes.io/ingress.class: nginx
    nginx.ingress.kubernetes.io/canary: "true"
    nginx.ingress.kubernetes.io/canary-weight: "30"
spec:
  rules:
  - host: master.example.com
    http:
      paths:
      - backend:
          serviceName: canary
          servicePort: 80
        path: /apis/echo

4) Visit nginx to view the gray deployment effect

2) Grayscale release based on http header

#在已经成功部署production服务和canary服务的基础上，创建以下两个ingress
[root@master canary]# cat production-ingress.yaml
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: production
  annotations:
    kubernetes.io/ingress.class: nginx
spec:
  rules:
  - host: master.ly-sky.com
    http:
      paths:
      - backend:
          serviceName: production
          servicePort: 80
        path: /apis/echo


[root@master canary]# cat canary-header-ingress.yaml
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: canary
  annotations:
    kubernetes.io/ingress.class: nginx
    nginx.ingress.kubernetes.io/canary: "true"
    nginx.ingress.kubernetes.io/canary-by-header: "yourcanaryheader"
    nginx.ingress.kubernetes.io/canary-by-header-value: "boy"
spec:
  rules:
  - host: master.ly-sky.com
    http:
      paths:
      - backend:
          serviceName: canary
          servicePort: 80
        path: /apis/echo

4) Visit nginx to view the gray deployment effect

According to the settings in ingress, requests with http header "yourcanaryheader: boy" will flow into the canary service.

When the value of the http header of yourcanaryheader is not "boy", the request flows into the product service.