Introduction to docker-compose.yml

A basic docker-compose.yml file starts with a version declaration, followed by a list of services. Each service can have its own configuration, and you can also define shared networks and volumes that services can use. The YAML format uses indentation to indicate structure, so be careful with spaces and alignment. Here is what you will typically see in a simple Compose file:

• Version: Specifies the Compose file format version;
• Services: Lists each containerized service, with its configuration;
• Networks: (Optional) Defines custom networks for service communication;
• Volumes: (Optional) Defines persistent data storage shared between services.

Steps to Launch and Manage Services Using Docker Compose

After defining your services in the Compose file, you can use Docker Compose commands to launch and manage your application. To start all services defined in your docker-compose.yml, run docker-compose up in the directory containing the file. This command will build images if needed, create containers, attach networks, and set up volumes as defined.

If you want to run the services in the background, add the -d flag: docker-compose up -d.

When you are finished, you can stop and remove all containers, networks, and volumes created by Compose with docker-compose down. This ensures a clean shutdown and removes resources, except for named volumes unless you add the -v flag.

By structuring your application in a docker-compose.yml file and using these commands, you can easily manage complex multi-container setups with a single configuration file.