在K8s上部署Go服务

柔光的暖阳◎ 2022-11-16 13:58 226阅读 0赞

### 目标 ###

镜像名：foxliang/go:v
    镜像内容：二进制文件，跑起来是个http服务，监听8080端口，接到请求会打印 This is version:{v} running in pod {hostname}，其中v是可变参数代表版本（字符串1.0这种），可以通过传参数进去
    
    1、将上面的二进制部署成一个服务跑起来
    2、服务需要包含3个副本
    3、可以外部访问这个服务
    4、可以对服务的版本进行滚动更新（通过传参进去）

### 1.先添加一个最简单的`golang`服务 ###

写一个**main.go文件**提供了一个 接口：

package main
    
    import (
    	"flag"
    
    	"github.com/gin-gonic/gin"
    	"net/http"
    	"os"
    )
    
    var version = flag.String("v", "v1", "v1")
    func main() {
    	router := gin.Default()
    
    	router.GET("", func(c *gin.Context) {
    		flag.Parse()
    		hostname, _ := os.Hostname()
    
    		c.String(http.StatusOK, "This is version:%s running in pod %s",*version,hostname)
    	})
    
    
    	router.Run(":8080")
    }

访问 [http://127.0.0.1:8080][http_127.0.0.1_8080]

This is version:1.3 running in pod f06afe0eabc4

### 2.为上面的`golang`服务写一个`Dockerfile`文件：（与**main.go**同目录） ###

FROM golang:latest AS build
    
    WORKDIR /go/src/test
    COPY . /go/src/test
    RUN go env -w GOPROXY=https://goproxy.cn,direct
    RUN CGO_ENABLED=0 go build -v -o main .
    
    FROM alpine AS api
    RUN mkdir /app
    COPY --from=build /go/src/test/main /app
    WORKDIR /app
    ENTRYPOINT ["./main", "-v" ,"1.3"]

### 3.然后构建`Docker`镜像并打包上传 ###

$ docker build  -t go:v1.3 .
    
    $ docker tag go:v1.3 foxliang/go:v1.3
    
    $ docker push foxliang/go:v1.3

### 4.构建go.yaml文件 ###

---
    apiVersion: apps/v1
    kind: Deployment
    metadata:
      name: go-deployment
      labels:
        app: go
    spec:
      selector:
        matchLabels:
          app: go
      replicas: 3
      minReadySeconds: 5
      strategy:
        type: RollingUpdate
        rollingUpdate:
          maxSurge: 1
          maxUnavailable: 1
      template:
        metadata:
          labels:
            app: go
        spec:
          containers:
          - image: foxliang/go:v1.3
            name: go
            imagePullPolicy: Always
            command: ["./main","-v","v1.3"]
            ports:
            - containerPort: 8080
              protocol: TCP
    ---
    apiVersion: v1
    kind: Service
    metadata:
      name: go-service
      labels:
        app: go
    spec:
      selector:
        app: go
      ports:
        - name: go-port
          protocol: TCP
          port: 8080
          targetPort: 8080
          nodePort: 31080
      type: NodePort

$ kubectl get pods
    NAME                             READY   STATUS    RESTARTS   AGE
    go-deployment-8675897977-6r9rd   1/1     Running   0          3m25s
    go-deployment-8675897977-c7kv2   1/1     Running   0          3m47s
    go-deployment-8675897977-f7dn2   1/1     Running   0          3m47s
    
    
    $ minikube service list
    |----------------------|---------------------------|--------------|---------------------------|
    |      NAMESPACE       |           NAME            | TARGET PORT  |            URL            |
    |----------------------|---------------------------|--------------|---------------------------|
    | default              | go-service                | go-port/8080 | http://192.168.79.2:31080 |

最后可编辑传参数 然后重新打包上传并部署可以得到下面的结果

for i in `seq 1 10`     
    do
      curl http://192.168.79.2:31080
      echo " "
    # echo $i
    done
    This is version:1.3 running in pod go-deployment-c4fd9b576-mb9b2 
    This is version:1.3 running in pod go-deployment-c4fd9b576-mb9b2 
    This is version:1.3 running in pod go-deployment-c4fd9b576-mb9b2 
    This is version:1.3 running in pod go-deployment-c4fd9b576-l7l6b 
    This is version:1.3 running in pod go-deployment-c4fd9b576-mb9b2 
    This is version:1.3 running in pod go-deployment-c4fd9b576-mb9b2 
    This is version:1.3 running in pod go-deployment-c4fd9b576-mb9b2 
    This is version:1.3 running in pod go-deployment-c4fd9b576-mb9b2 
    This is version:1.3 running in pod go-deployment-c4fd9b576-l7l6b 
    This is version:1.3 running in pod go-deployment-c4fd9b576-l7l6b

for i in `seq 1 10`
    do
      curl http://192.168.79.2:31080
      echo " "
    # echo $i
    done
    This is version:1.3 running in pod go-deployment-c4fd9b576-l7l6b 
    This is version:1.4 running in pod go-deployment-8675897977-c7kv2 
    This is version:1.3 running in pod go-deployment-c4fd9b576-l7l6b 
    This is version:1.3 running in pod go-deployment-c4fd9b576-l7l6b 
    This is version:1.3 running in pod go-deployment-c4fd9b576-mb9b2 
    This is version:1.3 running in pod go-deployment-c4fd9b576-l7l6b 
    This is version:1.3 running in pod go-deployment-c4fd9b576-l7l6b 
    This is version:1.4 running in pod go-deployment-8675897977-c7kv2 
    This is version:1.3 running in pod go-deployment-c4fd9b576-mb9b2 
    This is version:1.3 running in pod go-deployment-c4fd9b576-l7l6b

[http_127.0.0.1_8080]: http://127.0.0.1:8080/ping