Once docker-php is installed through composer you can start using it:

Connecting

By default, Docker-PHP does not make any assumption on where your docker daemon is, you will need to specify the entrypoint when creating the client.

By default, Docker-PHP uses the DOCKER_HOST environment variable to connect to a running dockerd, if not set it will use unix:///var/run/docker.sock. You can, however, connect to an arbitrary server by passing an instance of the transport entrypoint Docker\Http\Client:

<?php

$client = new Docker\Http\DockerClient(array(), 'tcp://127.0.0.1');
$docker = new Docker\Docker($client);

DockerClient is in fact a Guzzle Client with some default options.

Integration with Symfony

To integrate Docker-PHP into your Symfony Framework project we recommend creating a service in the service (dependency injection) container:

Example configuration: connecting to your local boot2docker machine with TLS disabled

parameters:
    docker_entrypoint: 'tcp://192.168.59.103:2375'

services:
    docker.client:
        class: Docker\Http\DockerClient
        arguments:
            - []
            - %docker_entrypoint%
            - ~
            - false
    docker:
        class: Docker\Docker
        arguments:
            - @docker.client

Example configuration: connecting to your local boot2docker machine with TLS enabled (default)

Create a combined key file first:

cd ~/.boot2docker/certs/boot2docker-vm/
cat key.pem > comb.pem
cat cert.pem >> comb.pem
cat ca.pem >> comb.pem

parameters:
    docker_entrypoint: 'tcp://192.168.59.103:2376'
    docker_cert_path: '/Users/username/.boot2docker/certs/boot2docker-vm'

services:
    docker.client:
        class: Docker\Http\DockerClient
        arguments:
            - []
            - %docker_entrypoint%
            -
                ssl:
                    local_cert: '%docker_cert_path%/comb.pem'
            - true
    docker:
        class: Docker\Docker
        arguments:
            - @docker.client

Docker-PHP is now available as docker. If you extend the default Controller from the Symfony FrameworkBundle you can write:

use Docker\Docker;

class ...
{
    public function indexAction()
    {
        /** @var Docker $docker */
        $docker = $this->get('docker');
        
        $imageManager = $docker->getImageManager();
        $containerManager = $docker->getContainerManager();
    }
}