最簡單的 K8S 部署文件編寫姿勢，沒有之一！

1. 頭疼編寫 K8S 部署文件？

• K8S yaml?參數(shù)很多，需要邊寫邊查？

• 保留回滾版本數(shù)怎么設(shè)？

• 如何探測啟動成功，如何探活？

• 如何分配和限制資源？

• 如何設(shè)置時區(qū)？否則打印日志是 GMT 標(biāo)準(zhǔn)時間

• 如何暴露服務(wù)供其它服務(wù)調(diào)用？

• 如何根據(jù) CPU 和內(nèi)存使用率來配置水平伸縮？

首先，你需要知道有這些知識點，其次要把這些知識點都搞明白也不容易，再次，每次編寫依然容易出錯！

2. 創(chuàng)建服務(wù)鏡像

前一篇文章?講解了如何快速創(chuàng)建自己的服務(wù)鏡像，不過為了演示，這篇文章我們以?redis:6-alpine?鏡像為例。

3. 完整 K8S 部署文件編寫過程

• 首先安裝?goctl?工具

GO111MODULE=on GOPROXY=https://goproxy.cn/,direct go get -u github.com/tal-tech/go-zero/tools/goctl

• 一鍵生成 K8S 部署文件

goctl kube deploy -name redis -namespace adhoc -image redis:6-alpine -o redis.yaml -port 6379

生成的?yaml?文件如下：

apiVersion: apps/v1
kind: Deployment
metadata:
  name: redis
  namespace: adhoc
  labels:
    app: redis
spec:
  replicas: 3
  revisionHistoryLimit: 5
  selector:
    matchLabels:
      app: redis
  template:
    metadata:
      labels:
        app: redis
    spec:
      containers:
      - name: redis
        image: redis:6-alpine
        lifecycle:
          preStop:
            exec:
              command: ["sh","-c","sleep 5"]
        ports:
        - containerPort: 6379
        readinessProbe:
          tcpSocket:
            port: 6379
          initialDelaySeconds: 5
          periodSeconds: 10
        livenessProbe:
          tcpSocket:
            port: 6379
          initialDelaySeconds: 15
          periodSeconds: 20
        resources:
          requests:
            cpu: 500m
            memory: 512Mi
          limits:
            cpu: 1000m
            memory: 1024Mi
        volumeMounts:
        - name: timezone
          mountPath: /etc/localtime
      volumes:
        - name: timezone
          hostPath:
            path: /usr/share/zoneinfo/Asia/Shanghai

---

apiVersion: v1
kind: Service
metadata:
  name: redis-svc
  namespace: adhoc
spec:
  ports:
    - port: 6379
  selector:
    app: redis

---

apiVersion: autoscaling/v2beta1
kind: HorizontalPodAutoscaler
metadata:
  name: redis-hpa-c
  namespace: adhoc
  labels:
    app: redis-hpa-c
spec:
  scaleTargetRef:
    apiVersion: apps/v1
    kind: Deployment
    name: redis
  minReplicas: 3
  maxReplicas: 10
  metrics:
  - type: Resource
    resource:
      name: cpu
      targetAverageUtilization: 80

---

apiVersion: autoscaling/v2beta1
kind: HorizontalPodAutoscaler
metadata:
  name: redis-hpa-m
  namespace: adhoc
  labels:
    app: redis-hpa-m
spec:
  scaleTargetRef:
    apiVersion: apps/v1
    kind: Deployment
    name: redis
  minReplicas: 3
  maxReplicas: 10
  metrics:
  - type: Resource
    resource:
      name: memory
      targetAverageUtilization: 80

• 部署服務(wù)，如果?adhoc?namespace 不存在的話，請先通過?kubectl create namespace adhoc?創(chuàng)建

$ kubectl apply -f redis.yaml
deployment.apps/redis created
service/redis-svc created
horizontalpodautoscaler.autoscaling/redis-hpa-c created
horizontalpodautoscaler.autoscaling/redis-hpa-m created

• 查看服務(wù)允許狀態(tài)

$ kubectl get all -n adhoc
NAME                         READY   STATUS    RESTARTS   AGE
pod/redis-585bc66876-5ph26   1/1     Running   0          6m5s
pod/redis-585bc66876-bfqxz   1/1     Running   0          6m5s
pod/redis-585bc66876-vvfc9   1/1     Running   0          6m5s

NAME                TYPE        CLUSTER-IP    EXTERNAL-IP   PORT(S)    AGE
service/redis-svc   ClusterIP   172.24.15.8           6379/TCP   6m5s

NAME                    READY   UP-TO-DATE   AVAILABLE   AGE
deployment.apps/redis   3/3     3            3           6m6s

NAME                               DESIRED   CURRENT   READY   AGE
replicaset.apps/redis-585bc66876   3         3         3       6m6s

NAME                                              REFERENCE          TARGETS   MINPODS   MAXPODS   REPLICAS   AGE
horizontalpodautoscaler.autoscaling/redis-hpa-c   Deployment/redis   0%/80%    3         10        3          6m6s
horizontalpodautoscaler.autoscaling/redis-hpa-m   Deployment/redis   0%/80%    3         10        3          6m6s

• 測試服務(wù)

$ kubectl run -i --tty --rm cli --image=redis:6-alpine -n adhoc -- sh
/data # redis-cli -h redis-svc
redis-svc:6379> set go-zero great
OK
redis-svc:6379> get go-zero
"great"

4. 總結(jié)

goctl?工具極大簡化了 K8S yaml 文件的編寫，提供了開箱即用的最佳實踐，并且支持了模板自定義。

如果覺得工具有幫助，歡迎?star??

5. 項目地址

https://github.com/tal-tech/go-zero

6. 微信交流群