使用istio對spring cloud kubernetes項目進行金絲雀釋出

本系列文章目錄

• (一)基礎k8s yaml腳本釋出
• (二)helm+shell腳本優化大量備援配置釋出
• (三)jenkins使用者稽核的流水化方式部署
• (四)service mesh(istio)服務網格化釋出
• (五)istio對項目進行金絲雀部署

其他相關文章

• spring-cloud-kubernetes之開發環境搭建
• spring cloud項目改造為spring-cloud-kubernetes項目
• 使用istio對spring cloud kubernetes項目進行金絲雀釋出

前言

上一篇文章《spring cloud項目改造為spring-cloud-kubernetes項目》以開源的spring-boot-cloud項目為例分享了如何将一個傳統的spring cloud項目換成spring cloud kubernetes項目，同時還示範了改造後中的Hystrix熔斷、本地服務調用本地服務、fabric8插件一鍵部署等功能。

這一篇為是對之前的文章《采用rancher2+kubernetes+skywalking部署springcloud項目(五[istio藍綠部署]-錯誤示範)》的一個後續，上次因為項目全采用的spring cloud原生元件來實作的微服務，但将項目部署到istio時因為原來spring cloud元件與istio中部分元件的沖突導緻沒能将藍綠部署示範成功。但目前原來的spring-boot-cloud項目中的元件已經用spring cloud kubernetes替換掉了，是以這裡決定再次進行嘗試用istio來示範如何進行金絲雀/灰階釋出

對于istio的環境的搭建直接參考之前的文章即可

部署改造後的spring-boot-cloud項目

這次僅部署config、gateway、svca-service、svcb-service，通路gateway項目會調用svca-service，svca-service又會調用svcb-service

其部署檔案如下:

#-------------config-----------------
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: config
spec:
  replicas: 1
  selector:
    matchLabels:
      app: config
  strategy:
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 0
    type: RollingUpdate
  template:
    metadata:
      labels:
        app: config
    spec:
      containers:
        - image: ccr.ccs.tencentyun.com/spring-boot-cloud/config:v3
          imagePullPolicy: Always
          name: config
          ports:
            - containerPort: 30876
              protocol: TCP
---
apiVersion: v1
kind: Service
metadata:
  name: config
spec:
  ports:
    - name: http
      port: 30876
      protocol: TCP
      targetPort: 30876
  selector:
    app: config
#-------------svca-service-----------------
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: svca-service
spec:
  replicas: 1
  selector:
    matchLabels:
      app: svca-service
  strategy:
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 0
    type: RollingUpdate
  template:
    metadata:
      labels:
        app: svca-service
    spec:
      containers:
        - image: ccr.ccs.tencentyun.com/spring-boot-cloud/svca-service:v3
          imagePullPolicy: Always
          name: svca-service
          ports:
            - containerPort: 8080
              protocol: TCP
---
apiVersion: v1
kind: Service
metadata:
  name: svca-service
spec:
  ports:
    - name: http
      port: 8080
      protocol: TCP
      targetPort: 8080
  selector:
    app: svca-service
#-------------svcb-service-----------------
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: svcb-service
spec:
  replicas: 1
  selector:
    matchLabels:
      app: svcb-service
  strategy:
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 0
    type: RollingUpdate
  template:
    metadata:
      labels:
        app: svcb-service
    spec:
      containers:
        - image: ccr.ccs.tencentyun.com/spring-boot-cloud/svcb-service:v3
          imagePullPolicy: Always
          name: svcb-service
          ports:
            - containerPort: 8070
              protocol: TCP
---
apiVersion: v1
kind: Service
metadata:
  name: svcb-service
spec:
  ports:
    - name: http
      port: 8070
      protocol: TCP
      targetPort: 8070
  selector:
    app: svcb-service
#-------------gateway-----------------
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: gateway
spec:
  replicas: 1
  selector:
    matchLabels:
      app: gateway
  strategy:
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 0
    type: RollingUpdate
  template:
    metadata:
      labels:
        app: gateway
    spec:
      containers:
        - image: ccr.ccs.tencentyun.com/spring-boot-cloud/gateway:v3
          imagePullPolicy: Always
          name: gateway
          ports:
            - containerPort: 8060
              protocol: TCP
---
apiVersion: v1
kind: Service
metadata:
  name: gateway
spec:
  ports:
    - name: http
      port: 8060
      protocol: TCP
      targetPort: 8060
  selector:
    app: gateway
---
           

如果啟動時釋出有權限不足的話，記得給serviceaccount權重限，要不然可能會報下面這樣的錯誤

具體的操作方式參考上一篇文章中k8s rbac部分

部署好了項目之後，接着添加virtualservice和gateway，以通路gateway項目

apiVersion: networking.istio.io/v1alpha3
kind: Gateway
metadata:
  name: gateway-gateway
  namespace: istio-system
spec:
  selector:
    istio: ingressgateway # use istio default controller
  servers:
  - port:
      number: 80
      name: http
      protocol: HTTP
    hosts:
    - "gateway.springcloud.com"
---
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: gateway
spec:
  hosts:
  - "gateway.springcloud.com"
  gateways:
  - istio-system/gateway-gateway #can omit the namespace if gateway is in same namespace as virtual service
  http:
  - route:
    - destination:
        host: gateway
        port:
          number: 8060
---
           

然後再通路測試一下：

由于上面gateway中配置的是gateway.springcloud.com這上域名，是以需要在通路的機器上配一下host

使用istio釋出注意點

在使用istio部署spring cloud kubernetes項目前記得将kubernetes的ribbon模式修改為service模式，預設是pod模式。

如果是pod模式的話，istio中對于virtualservice的配置是不會生效的

spring:
  cloud:
    kubernetes:
      ribbon:
        mode: service
           

svcb-service藍綠部署

為了示範友善，這裡對svcb-service進行藍綠部署，準備好2個版本分别為v3和v5，不同的版本會輸出不同的内容

其svcb-service的deployment配置檔案如下:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: svcb-service-v3
spec:
  replicas: 1
  selector:
    matchLabels:
      app: svcb-service
  strategy:
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 0
    type: RollingUpdate
  template:
    metadata:
      labels:
        app: svcb-service
        version: v3
    spec:
      containers:
        - image: ccr.ccs.tencentyun.com/spring-boot-cloud/svcb-service:v3
          imagePullPolicy: Always
          name: svca-service
          ports:
            - containerPort: 8070
              protocol: TCP
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: svcb-service-v5
spec:
  replicas: 1
  selector:
    matchLabels:
      app: svcb-service
  strategy:
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 0
    type: RollingUpdate
  template:
    metadata:
      labels:
        app: svcb-service
        version: v5
    spec:
      containers:
        - image: ccr.ccs.tencentyun.com/spring-boot-cloud/svcb-service:v5
          imagePullPolicy: Always
          name: svcb-service
          ports:
            - containerPort: 8070
              protocol: TCP
           

執行後測試一下，會出現一會兒輸出V3一會兒輸出V5的情況

通路截圖如下：

通過觀察請求結果我們可以看到，目前因為有兩個版本的svcb-service，是以通路時也會輪詢v3和v5兩個版本的服務。其kiali監控圖如下：

接下來加virtualservice，來讓所有對于svcb-service的請求都發到v5版本上去

apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: svcb-service
spec:
  hosts:
  - svcb-service
  http:
  - route:
    - destination:
        host: svcb-service
        subset: v5
---

apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
  name: svcb-service
spec:
  host: svcb-service
  subsets:
  - name: v3
    labels:
      version: v3
  - name: v5
    labels:
      version: v5
           

上面的操作添加了一個VirtualService并綁定了一個DestinationRule，其VirtualService中讓所有的svcb-service請求都轉發到了labels為v5的pod中

此時再來測試一下效果

從圖檔可以看出，所有的請求全發到了v5版本的svcb-service中了

金絲雀/灰階釋出示範

感覺所謂的金絲雀部署就是按照比例來進行部署，有了藍綠部署金絲雀部署就簡單了，直接來個配置檔案修改virtualservice的配置就行了：

apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: svcb-service
spec:
  hosts:
  - svcb-service
  http:
  - route:
    - destination:
        host: svcb-service
        subset: v3
      weight: 90
    - destination:
        host: svcb-service
        subset: v5
      weight: 10
---
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
  name: svcb-service
spec:
  host: svcb-service
  subsets:
  - name: v3
    labels:
      version: v3
  - name: v5
    labels:
      version: v5
           

示範一下:

從結果中可以看出，在加上金絲雀釋出後，根據請求的比例差不多10%的請求被轉發到了V5版本中，其餘的請求轉發到了V3版本中

最後想說

在體驗了spring cloud kubernetes+istio之後最後想說,service mesh果然名不虛傳