docker-compose tips

docker-compose额外增加命令行

不过还没去测试

https://stackoverflow.com/questions/71786923/docker-compose-how-to-run-bash-commands-after-container-has-started-without-ov

you have three main ways to run a command after the container starts:

• with docker exec -d someContainer some command from the command line,
• with CMD ["some", "command"] from your Dockerfile
• with command: some command from a docker-compose file

Docker Compose - How to execute multiple commands?

https://stackoverflow.com/questions/30063907/docker-compose-how-to-execute-multiple-commands

I recommend using sh as opposed to bash because it is more readily available on most Unix based images (alpine, etc).

Here is an example docker-compose.yml:

version: '3'

services:
  app:
    build:
      context: .
    command: >
      sh -c "python manage.py wait_for_db &&
             python manage.py migrate &&
             python manage.py runserver 0.0.0.0:8000"

db:
  image: postgres
web:
  image: app
  command: python manage.py runserver 0.0.0.0:8000
  volumes:
    - .:/code
  ports:
    - "8000:8000"
  links:
    - db
  depends_on:
    - migration
migration:
  build: .
  image: app
  command: python manage.py migrate
  volumes:
    - .:/code
  links:
    - db
  depends_on:
    - db

docker-compose, run a script after container has started?

启动一个额外的临时镜像, 只用来运行命令, 初始化第一个镜像.

https://stackoverflow.com/questions/47615751/docker-compose-run-a-script-after-container-has-started

This is the way I use for calling a script after a container is started without overriding the entrypoint.

In my example, I used it for initializing the replicaset of my local MongoDB

services:
  mongo:
    image: mongo:4.2.8
    hostname: mongo
    container_name: mongodb
    entrypoint: ["/usr/bin/mongod","--bind_ip_all","--replSet","rs0"]
    ports:
      - 27017:27017
  mongosetup:
    image: mongo:4.2.8
    depends_on:
      - mongo
    restart: "no"
    entrypoint: [ "bash", "-c", "sleep 10 && mongo --host mongo:27017 --eval 'rs.initiate()'"]      

In the first part, I simply launch my service (mongo) The second service use a "bash" entry point AND a restart: no <= important I also use a depends_on between service and setup service for manage the launch order.