Nicolas De Loof
c74f6f8cb6
Three tests failed 9 CI runs across 5 branches this week, all on asynchronous-observation races, none reproducible locally: - RequireServiceState asserted on a single `compose ps` snapshot; the daemon reports state transitions asynchronously from everything else a test observes (TestUpDependenciesNotStopped saw 'created' while the container's logs were already flowing). It now polls until the state converges (15s bound). - TestAttachRestart counted restart log lines in a snapshot taken as soon as the third exit notice appeared; exit notices come from the events monitor while log lines come from the re-attached logs stream — two channels with no ordering between them. The count is now awaited like the exit notices already were; a genuinely lost line still fails, by timeout. - TestUpExitCodeFromContainerKilled ran a full up+abort cycle under a 60s ceiling, once exceeded on a loaded oldstable runner; raised to 120s. Signed-off-by: Nicolas De Loof <[email protected]>
Table of Contents
Docker Compose
Docker Compose is a tool for running multi-container applications on Docker
defined using the Compose file format.
A Compose file is used to define how one or more containers that make up
your application are configured.
Once you have a Compose file, you can create and start your application with a
single command: docker compose up.
Note
: About Docker Swarm Docker Swarm used to rely on the legacy compose file format but did not adopt the compose specification so is missing some of the recent enhancements in the compose syntax. After acquisition by Mirantis swarm isn't maintained by Docker Inc, and as such some Docker Compose features aren't accessible to swarm users.
Where to get Docker Compose
Windows and macOS
Docker Compose is included in Docker Desktop for Windows and macOS.
Linux
You can download Docker Compose binaries from the release page on this repository.
Rename the relevant binary for your OS to docker-compose and copy it to $HOME/.docker/cli-plugins
Or copy it into one of these folders to install it system-wide:
/usr/local/lib/docker/cli-pluginsOR/usr/local/libexec/docker/cli-plugins/usr/lib/docker/cli-pluginsOR/usr/libexec/docker/cli-plugins
(might require making the downloaded file executable with chmod +x)
Quick Start
Using Docker Compose is a three-step process:
- Define your app's environment with a
Dockerfileso it can be reproduced anywhere. - Define the services that make up your app in
compose.yamlso they can be run together in an isolated environment. - Lastly, run
docker compose upand Compose will start and run your entire app.
A Compose file looks like this:
services:
web:
build: .
ports:
- "5000:5000"
volumes:
- .:/code
redis:
image: redis
Contributing
Want to help develop Docker Compose? Check out our contributing documentation.
If you find an issue, please report it on the issue tracker.
Legacy
The Python version of Compose is available under the v1 branch.