go代码
写一个最简单的http服务器:
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") }
测试下能不能用:
go run main.go
启动成功后,curl测试:
(base) tioncico@appledeMacBook-Pro test % curl 127.0.0.1:8080 This is version:v1 running in pod appledeMacBook-Pro.local%
dockerfile
编写go服务的dockerfile,在main.go同级目录编写(多阶段构建dockerfile):
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 \["./main", "-v" ,"1.0.1"\]
构建docker镜像并打包上传
docker build -t go:v1.0.1 . # 编译镜像 docker tag go:v1.0.1 tioncico/go:v1.0.1 # 增加tag docker push tioncico/go:v1.0.1 # 上传到docker hub
此时,在dockerhub上,即可看到编译好的镜像:
编写k8s yaml文件
新增 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: tioncico/go:v1.0.1 name: go imagePullPolicy: Always command: \["./main","-v","v1.0.1"\] 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: 30080 type: NodePort
k8s部署
kubectl apply -f go.yaml
即可部署成功,查看pod状态:
root@master:/home/tioncico# kubectl get pods NAME READY STATUS RESTARTS AGE go-deployment-86f769995d-6j4pq 1/1 Running 0 2m20s go-deployment-86f769995d-8pcsd 1/1 Running 0 2m20s go-deployment-86f769995d-lz7vf 1/1 Running 0 2m20s nginx-7cbb8cd5d8-w9tn2 1/1 Running 3 (140m ago) 28h
可看到,已经部署了3台,访问 集群任意一个节点ip:30080端口,可查看效果:
root@master:/home/tioncico# curl http://192.168.192.9:30080 This is version:v1.0.1 running in pod go-deployment-86f769995d-lz7vf root@master:/home/tioncico# curl http://192.168.192.9:30080 ^C root@master:/home/tioncico# curl http://192.168.192.10:30080 This is version:v1.0.1 running in pod go-deployment-86f769995d-8pcsd root@master:/home/tioncico#
为什么需要上传到docker hub?
在上面的教程中可以看到,我们先将镜像放到了docker hub,才开始进行k8s部署,这样相当于把自己的项目放到了公共的仓库,十分不安全
原因是: k8s有多个节点,如果我们只在一个节点编译镜像,其他节点就无法获取到这个自己编译后的镜像
解决方案有2种:
1:将所有镜像都编译到其他节点中去
2:创建一个私有的docker仓库,让k8s集群通过私有仓库去进行pull images 即可
