本系列文章目录

• (一)基础k8s yaml脚本发布
• (二)helm+shell脚本优化大量冗余配置发布
• (三)jenkins用户审核的流水化方式部署
• (四)service mesh(istio)服务网格化发布
• (五)istio对项目进行金丝雀部署

其他相关文章

• spring-cloud-kubernetes之开发环境搭建
• spring cloud项目改造为spring-cloud-kubernetes项目
• 使用istio对spring cloud kubernetes项目进行金丝雀发布

前言

上一篇文章《spring cloud项目改造为spring-cloud-kubernetes项目》以开源的spring-boot-cloud项目为例分享了如何将一个传统的spring cloud项目换成spring cloud kubernetes项目，同时还演示了改造后中的Hystrix熔断、本地服务调用本地服务、fabric8插件一键部署等功能。

这一篇为是对之前的文章《采用rancher2+kubernetes+skywalking部署springcloud项目(五[istio蓝绿部署]-错误演示)》的一个后续，上次因为项目全采用的spring cloud原生组件来实现的微服务，但将项目部署到istio时因为原来spring cloud组件与istio中部分组件的冲突导致没能将蓝绿部署演示成功。但目前原来的spring-boot-cloud项目中的组件已经用spring cloud kubernetes替换掉了，所以这里决定再次进行尝试用istio来演示如何进行金丝雀/灰度发布

对于istio的环境的搭建直接参考之前的文章即可

部署改造后的spring-boot-cloud项目

这次仅部署config、gateway、svca-service、svcb-service，访问gateway项目会调用svca-service，svca-service又会调用svcb-service

其部署文件如下:

#-------------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
---

如果启动时发布有权限不足的话，记得给serviceaccount加权限，要不然可能会报下面这样的错误

具体的操作方式参考上一篇文章中k8s rbac部分

部署好了项目之后，接着添加virtualservice和gateway，以访问gateway项目

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
---

然后再访问测试一下：

由于上面gateway中配置的是gateway.springcloud.com这上域名，所以需要在访问的机器上配一下host

使用istio发布注意点

在使用istio部署spring cloud kubernetes项目前记得将kubernetes的ribbon模式修改为service模式，默认是pod模式。
如果是pod模式的话，istio中对于virtualservice的配置是不会生效的

spring:
  cloud:
    kubernetes:
      ribbon:
        mode: service

svcb-service蓝绿部署

为了演示方便，这里对svcb-service进行蓝绿部署，准备好2个版本分别为v3和v5，不同的版本会输出不同的内容

其svcb-service的deployment配置文件如下:

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

执行后测试一下，会出现一会儿输出V3一会儿输出V5的情况

访问截图如下：

通过观察请求结果我们可以看到，目前因为有两个版本的svcb-service，所以访问时也会轮询v3和v5两个版本的服务。其kiali监控图如下：

接下来加virtualservice，来让所有对于svcb-service的请求都发到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个VirtualService并绑定了一个DestinationRule，其VirtualService中让所有的svcb-service请求都转发到了labels为v5的pod中

此时再来测试一下效果

从图片可以看出，所有的请求全发到了v5版本的svcb-service中了

金丝雀/灰度发布演示

感觉所谓的金丝雀部署就是按照比例来进行部署，有了蓝绿部署金丝雀部署就简单了，直接来个配置文件修改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

演示一下:

从结果中可以看出，在加上金丝雀发布后，根据请求的比例差不多10%的请求被转发到了V5版本中，其余的请求转发到了V3版本中

最后想说

在体验了spring cloud kubernetes+istio之后最后想说,service mesh果然名不虚传