Installing

Pull the composer image from the Docker hub:

docker pull composer

Using

Run the composer image:

docker run --rm -it \
    -v $(pwd):/app \
    composer install

You can mount the Composer home directory from your host inside the Container to share caching and configuration files:

docker run --rm -it \
    -v $(pwd):/app \
    -v $COMPOSER_HOME:/composer \
    composer install

By default, Composer runs as root inside the container. This can lead to permission issues on your host filesystem. You can run Composer as yourself:

docker run --rm -it \
    -v $(pwd):/app \
    -e DOCKER_UID=$UID \
    -e DOCKER_USER=$USER \
    composer install

Suggestions

PHP Extensions

We strive to deliver an image that is as lean as possible, aimed at running Composer only.

Sometimes dependencies or composer scripts require the availability of certain PHP extensions. In this scenario, you have two options:

• Pass the --ignore-platform-reqs and --no-scripts flags to install or update:

  docker run --rm -it \
      -v $(pwd):/app \
      composer install --no-scripts -ignore-platform-reqs

• Create your own image (possibly by extending FROM composer).

Local runtime/binary

If you want to be able to run composer as if it was installed on your host locally, you can define the following function in your ~/.bashrc, ~/.zshrc or similar:

composer () {
    tty=
    tty -s && tty=-t
    docker run \
        $tty \
        -i \
        --rm \
        -e DOCKER_UID=$UID \
        -e DOCKER_USER=$USER \
        -v $(pwd):/app \
        composer "$@"
}