Docker Compose Cheatsheet

Sample docker-compose.yml file

Here is a sample docker-compose.yml file:

version: '3.9'
services:

  mysqldb:
    image: mysql:5.7
    ports:
      - 3306:3306
    volumes:
    - ./docker/mysql/data:/var/lib/mysql
    - ./docker/mysql/my.cnf:/etc/mysql/my.cnf
    - ./docker/mysql/run:/var/run/mysqld
    environment:
      MYSQL_ROOT_PASSWORD: rootpassword
      MYSQL_DATABASE: my_db
      MYSQL_USER: my
      MYSQL_PASSWORD: mypassword

  redis:
    image: "redis:alpine"
    ports:
      - 6379:6379

  web:
    build: .
    stdin_open: true
    tty: true
    environment:
      DJANGO_SETTINGS_MODULE: my_project.settings.dev_docker
    ports:
      - 8000:8000
    volumes:
      - ./:/src
    command: python manage.py runserver 0.0.0.0:8000
    depends_on:
      - mysqldb
      - redis
    links:
      - mysqldb:mysqldb
      - redis:redis
      %

Build a Docker Compose Setup

The following command fetches all the dependency images and builds the image, but doesn’t run the image as a container.

docker-compose build

Launch a Docker Compose Setup

The following command builds the image, if it is not already built, and launches the container:

docker-compose up

Shutdown Docker Compose Setup

The following command shuts down all the running containers setup with docker-compose up.

docker-compose down

Check State of Docker Compose Containers

The following command shows the state of all the containers managed by docker compose.

docker-compose ps

Run a Command on a Running Container in the Docker Compose Setup

The following command runs a given command (let’s say ls -lah in a container that is running that is managed by docker compose)

docker-compose run web sh -c "ls -lah"

Let’s break down this command:

• docker-compose run - runs the command in a container managed by docker-compose.
• web - the name of the container that we want to run the command in.
• sh -c "ls -lah" - invokes sh shell, and runs the ls -lah command inside it.