Kubernetes + Compose = Kompose
从 Docker Compose 到 Kubernetes 的转换工具
什么是 Kompose?
Kompose 是 dockercompose 到 Kubernetes （或 OpenShift) 等容器编排器的转换工具。
为什么开发者喜欢它？
- 使用 Docker Compose 简化开发过程，然后将容器部署到生产集群
- 转换你的
docker-compose.yaml需要一个简单的命令kompose convert
易如反掌
- 找一个
docker-compose.yaml文件； - 执行：
kompose convert - 执行
kubectl apply并检查您的 k8s 集群为您新部署的容器！
$ wget https://raw.githubusercontent.com/kubernetes/kompose/master/examples/docker-compose-v3.yaml -O docker-compose.yaml $ kompose convert $ kubectl apply -f . $ kubectl get po NAME READY STATUS RESTARTS AGE frontend-591253677-5t038 1/1 Running 0 10s redis-master-2410703502-9hshf 1/1 Running 0 10s redis-slave-4049176185-hr1lr 1/1 Running 0 10s BASH |
实战
比如我要在 K8S 上安装 RssHub，这是官方提供的 docker-compose.yml:
version: '3' services: rsshub: image: diygod/rsshub restart: always ports: - '1200:1200' environment: NODE_ENV: production CACHE_TYPE: redis REDIS_URL: 'redis://redis:6379/' PUPPETEER_WS_ENDPOINT: 'ws://browserless:3000' depends_on: - redis - browserless browserless: # See issue 6680 image: browserless/chrome:1.43-chrome-stable restart: always ulimits: core: hard: 0 soft: 0 redis: image: redis:alpine restart: always volumes: - redis-data:/data volumes: redis-data: YAML |
执行 kompose convert 后，从 docker-compose.yml 生成以下文件：
$ ll .rw-r--r-- 711 casey 1 Dec 21:20 browserless-deployment.yaml .rw-r--r-- 715 casey 1 Dec 21:20 docker-compose.yml .rw-r--r-- 243 casey 1 Dec 21:20 redis-data-persistentvolumeclaim.yaml .rw-r--r-- 867 casey 1 Dec 21:20 redis-deployment.yaml .rw-r--r-- 1.0k casey 1 Dec 21:20 rsshub-deployment.yaml .rw-r--r-- 352 casey 1 Dec 21:20 rsshub-service.yaml BASH |
每个 docker-compose 容器，会生成为一个 deployment，并为你自动转换好 label 和 env 等字段，以 rsshub-deployment.yaml 为例：
apiVersion: apps/v1 kind: Deployment metadata: annotations: kompose.cmd: kompose convert kompose.version: 1.26.0 (40646f47) creationTimestamp: null labels: io.kompose.service: rsshub name: rsshub spec: replicas: 1 selector: matchLabels: io.kompose.service: rsshub strategy: {} template: metadata: annotations: kompose.cmd: kompose convert kompose.version: 1.26.0 (40646f47) creationTimestamp: null labels: io.kompose.service: rsshub spec: containers: - env: - name: CACHE_TYPE value: redis - name: NODE_ENV value: production - name: PUPPETEER_WS_ENDPOINT value: ws://browserless:3000 - name: REDIS_URL value: redis://redis:6379/ image: diygod/rsshub name: rsshub ports: - containerPort: 1200 resources: {} restartPolicy: Always status: {} YAML |
Docker compose 的 ports 部分，会转换为 SVC，以 rsshub-service.yaml 为例：
apiVersion: v1 kind: Service metadata: annotations: kompose.cmd: kompose convert kompose.version: 1.26.0 (40646f47) creationTimestamp: null labels: io.kompose.service: rsshub name: rsshub spec: ports: - name: "1200" port: 1200 targetPort: 1200 selector: io.kompose.service: rsshub status: loadBalancer: {} YAML |
Docker compose 的 volumes 字段，会转换为 PVC，以 redis-data-persistentvolumeclaim.yaml 为例：
apiVersion: v1 kind: PersistentVolumeClaim metadata: creationTimestamp: null labels: io.kompose.service: redis-data name: redis-data spec: accessModes: - ReadWriteOnce resources: requests: storage: 100Mi status: {} YAML |
安逸！
安装
# Linux curl -L https://github.com/kubernetes/kompose/releases/download/v1.25.0/kompose-linux-amd64 -o kompose # macOS curl -L https://github.com/kubernetes/kompose/releases/download/v1.25.0/kompose-darwin-amd64 -o kompose chmod +x kompose sudo mv ./kompose /usr/local/bin/kompose BASH |
