kompose is a tool to help users who are familiar with docker-compose move to Kubernetes. kompose takes a Docker Compose file and translates it into Kubernetes resources.
kompose is a convenience tool to go from local Docker development to managing your application with Kubernetes. Transformation of the Docker Compose format to Kubernetes resources manifest may not be exact, but it helps tremendously when first deploying an application on Kubernetes.
Install:
curl -L https://github.com/kubernetes/kompose/releases/download/v1.18.0/kompose-darwin-amd64 -o kompose chmod +x kompose sudo mv ./kompose /usr/local/bin/kompose
We have a Docker compose file which setup Node, Nginx, Redis, MongoDB.
# 1. Update config values (localhost --> mongo and localhost --> redis) in config/config.development.json if necessary. # 2. Set APP_ENV environment variable by running the following command in your commnand window (see the notes below if on Windows). # export APP_ENV=development or export APP_ENV=production # export DOCKER_ACCT=codewithdan # NOTE: If you're on Windows use one of the following commands to create the environment variables. # Use 'codewithdan' for the account if you want to run in Kubernetes (see the readme). Otherwise, you can substitute your own # Docker account for the value if you'd like. # For the standard Windows DOS command shell use `set` instead of `export` for environment variables. # For Windows Powershell use $env:APP_ENV = "value". # 3. Remove "node" service volume (below) if doing a production build # 4. Run docker-compose build # 5. Run docker-compose up # 6. Live long and prosper version: "3.1" services: nginx: container_name: nginx image: ${DOCKER_ACCT}/nginx build: context: . dockerfile: .docker/nginx.${APP_ENV}.dockerfile # links are deprecated (networks are used instead for communication and # depends_on for upstream node name in nginx config) # links: # - node1:node1 # - node2:node2 # - node3:node3 depends_on: - node ports: - "80:80" - "443:443" networks: - codewithdan-network node: container_name: node-codewithdan image: ${DOCKER_ACCT}/node-codewithdan build: context: . dockerfile: .docker/node-codewithdan.${APP_ENV}.dockerfile ports: - "8080" volumes: - .:/var/www/codewithdan working_dir: /var/www/codewithdan env_file: - ./.docker/env/app.${APP_ENV}.env depends_on: - mongo - redis networks: - codewithdan-network # Removing these for those wanting to run Kubernetes as well (since replica sets would scale pods with containers) # node2: # container_name: node-codewithdan-2 # image: ${DOCKER_ACCT}/node-codewithdan # build: # context: . # dockerfile: .docker/node-codewithdan.${APP_ENV}.dockerfile # ports: # - "8080" # volumes: # - .:/var/www/codewithdan # working_dir: /var/www/codewithdan # env_file: # - ./.docker/env/app.${APP_ENV}.env # depends_on: # - mongo # - redis # networks: # - codewithdan-network # node3: # container_name: node-codewithdan-3 # image: ${DOCKER_ACCT}/node-codewithdan # build: # context: . # dockerfile: .docker/node-codewithdan.${APP_ENV}.dockerfile # ports: # - "8080" # volumes: # - .:/var/www/codewithdan # working_dir: /var/www/codewithdan # env_file: # - ./.docker/env/app.${APP_ENV}.env # depends_on: # - mongo # - redis # networks: # - codewithdan-network mongo: container_name: mongo image: ${DOCKER_ACCT}/mongo build: context: . dockerfile: .docker/mongo.dockerfile ports: - "27017:27017" env_file: - ./.docker/env/mongo.${APP_ENV}.env networks: - codewithdan-network redis: container_name: redis image: ${DOCKER_ACCT}/redis build: context: . dockerfile: .docker/redis.${APP_ENV}.dockerfile ports: - "6379" networks: - codewithdan-network # cadvisor: # container_name: cadvisor # image: google/cadvisor # volumes: # - /:/rootfs:ro # - /var/run:/var/run:rw # - /sys:/sys:ro # - /var/lib/docker/:/var/lib/docker:ro # ports: # - "8080:8080" # networks: # - codewithdan-network networks: codewithdan-network: driver: bridge
Run:
export APP_ENV=development // or export APP_ENV=production export DOCKER_ACCT=codewithdan
Then, we can convert Docker compose file to Kubernetes files:
kompose conver // create multi yml files for each services // or output only one file kompose conver --out test.yml