Compose command compatibility with docker-compose

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The compose command in the Docker CLI supports most of the docker-compose commands and flags. It is expected to be a drop-in replacement for docker-compose.

If you see any Compose functionality that is not available in the compose command, create an issue in the Compose GitHub repository, so we can prioritize it.

Commands or flags not yet implemented

The following commands have not been implemented yet, and may be implemented at a later time. Let us know if these commands are a higher priority for your use cases.

compose build --memory: This option is not yet supported by buildkit. The flag is currently supported, but is hidden to avoid breaking existing Compose usage. It does not have any effect.

Flags that will not be implemented

The list below includes the flags that we are not planning to support in Compose in the Docker CLI, either because they are already deprecated in docker-compose, or because they are not relevant for Compose in the Docker CLI.

• compose ps --filter KEY-VALUE Not relevant due to its complicated usage with the service command and also because it is not documented properly in docker-compose.
• compose rm --all Deprecated in docker-compose.
• compose scale Deprecated in docker-compose (use compose up --scale instead)

Global flags:

• --compatibility has been resignified Docker Compose V2. This now means that in the command running V2 will behave as V1 used to do.
  • One difference is in the word separator on container names. V1 used to use _ as separator while V2 uses - to keep the names more hostname friendly. So when using --compatibility Docker Compose should use _ again. Just make sure to stick to one of them otherwise Docker Compose will not be able to recognize the container as an instance of the service.

Config command

The config command is intended to show the configuration used by Docker Compose to run the actual project. As we know, at some parts of the Compose file have a short and a long format. For example, the ports entry. In the example below we can see the config command expanding the ports section:

docker-compose.yml:

services:
  web:
    image: nginx
    ports:
      - 80:80

With $ docker compose config the output turns into:

services:
  web:
    image: nginx
    networks:
      default: null
    ports:
    - mode: ingress
      target: 80
      published: 80
      protocol: tcp
networks:
  default:
    name: workspace_default

The result above is a full size configuration of what will be used by Docker Compose to run the project.

New commands introduced in Compose v2

Copy

The cp command is intended to copy files or folders between service containers and the local filesystem.
This command is a bidirectional command, we can copy from or to the service containers.

Copy a file from a service container to the local filesystem:

$ docker compose cp my-service:~/path/to/myfile ~/local/path/to/copied/file

We can also copy from the local filesystem to all the running containers of a service:

$ docker compose cp --all ~/local/path/to/source/file my-service:~/path/to/copied/file

List

The ls command is intended to list the Compose projects. By default, the command only lists the running projects, we can use flags to display the stopped projects, to filter by conditions and change the output to json format for example.

$ docker compose ls --all --format json
[{"Name":"dockergithubio","Status":"exited(1)","ConfigFiles":"/path/to/docker.github.io/docker-compose.yml"}]

Use --project-name with Compose commands

With the GA version of Compose, you can run some commands:

• outside of directory containing the project compose file
• or without specifying the path of the Compose with the --file flag
• or without specifying the project directory with the --project-directory flag

When a compose project has been loaded once, we can just use the -p or --project-name to reference it:

$ docker compose -p my-loaded-project restart my-service

This option works with the start, stop, restart and down commands.