Docker Compose as a Docker CLI plugin

README.md

Run Docker Compose as a Docker CLI plugin

Just a quick fun experiment to try to make docker-compose work as a Docker CLI plugin

• docker/cli#1534 CLI Plugins Design
• docker/cli#1564 Basic framework for writing and running CLI plugins

To use it (assuming you have docker compose installed):

1. download a and install nightly build of the docker cli (linux macOS)

2. create the plugins directory

   mkdir -p ~/.docker/cli-plugins

3. download the "plugin", and save it as ~/.docker/cli-plugins/docker-compose (note: no .sh extension!)

   curl https://gist.githubusercontent.com/thaJeztah/b7950186212a49e91a806689e66b317d/raw/36d4c5854523502deed5b56842b0d34cd6ec0f70/docker-compose-plugin.sh > ~/.docker/cli-plugins/docker-compose 

4. make it executable

   chmod +x ~/.docker/cli-plugins/docker-compose

5. run the help command on the nightly docker cli to verify the plugin was installed

   ./docker help
   ...
   Commands:
     build                     Build an image from a Dockerfile
     compose     (Docker)      Define and run multi-container applications
     login                     Log in to a Docker registry
     logout                    Log out from a Docker registry

6. enjoy!

   ./docker compose help
   Define and run multi-container applications with Docker.
   
   Usage:
     docker-compose [-f <arg>...] [options] [COMMAND] [ARGS...]
     docker-compose -h|--help
   
   Options:
     -f, --file FILE             Specify an alternate compose file
                                 (default: docker-compose.yml)
     -p, --project-name NAME     Specify an alternate project name

docker-compose-plugin.sh

#!/usr/bin/env bash

docker_cli_plugin_metadata() {
	if [ -z "$DOCKER_COMPOSE_VERSION" ]; then
		export DOCKER_COMPOSE_VERSION="$(docker-compose --version | cut -d " " -f 3 | cut -d "," -f 1)"
	fi

	local vendor="Docker"
	local url="https://www.docker.com"
	local description="Define and run multi-container applications"
	cat <<-EOF
	{"SchemaVersion":"0.1.0","Vendor":"${vendor}","Version":"${DOCKER_COMPOSE_VERSION}","ShortDescription":"${description}","URL":"${url}"}
EOF
}

case "$1" in
	docker-cli-plugin-metadata)
		docker_cli_plugin_metadata
		;;
	*)
		exec "docker-$@"
		;;
esac

Yeah, it's not necessary for docker-compose anymore, but your little shell script was super useful to experiment with the CLI plugin concept, since it makes it really easy to answer the metadata request correctly.

Side note, your link to the nightly build for the Linux cli didn't have any packages newer than 2019. Did you mean to link to https://download.docker.com/linux/static/test/aarch64/? That directory includes much newer builds, including docker-22.06.0-beta.0.tgz dated June 6, 2022 (a week ago as of this writing).