Configure a container

Combine ports, mounts, environment variables and restart policy in a request.

Container creation is a nested request. Publishing a port belongs in HostConfig, while the container-side port declaration belongs in ContainersCreatePostBody. Declaring an exposed port alone does not publish it.

Ports, a bind mount and restart policy

This example creates, but does not start, a development container. Pull nginx:alpine first using the image pull recipe. Create /srv/docker-php-example/html on the daemon host, with an index.html file, before running it. Choose an unused example name and host port.

<?php

require __DIR__ . '/vendor/autoload.php';

use Docker\API\Model\ContainersCreatePostBody;
use Docker\API\Model\HostConfig;
use Docker\API\Model\Mount;
use Docker\API\Model\PortBinding;
use Docker\API\Model\RestartPolicy;
use Docker\Docker;

$docker = Docker::create();

$binding = new PortBinding();
$binding->setHostIp('127.0.0.1');
$binding->setHostPort('8080');

$mount = new Mount();
$mount->setType('bind');
$mount->setSource('/srv/docker-php-example/html');
$mount->setTarget('/usr/share/nginx/html');
$mount->setReadOnly(true);

$restart = new RestartPolicy();
$restart->setName('no');

$host = new HostConfig();
$host->setPortBindings(new ArrayObject(['80/tcp' => [$binding]]));
$host->setMounts([$mount]);
$host->setRestartPolicy($restart);

$body = new ContainersCreatePostBody();
$body->setImage('nginx:alpine');
$body->setEnv(['EXAMPLE_MODE=development']);
$body->setLabels(new ArrayObject(['docker-php-example' => 'true']));
$body->setExposedPorts(new ArrayObject(['80/tcp' => new ArrayObject()]));
$body->setHostConfig($host);

$created = $docker->containerCreate($body, ['name' => 'docker-php-example-web']);
printf("Created %s\n", $created->getId());

Review the returned ID, then use containerStart($created->getId()) to start that container. The example deliberately leaves it stopped. Remove only that created container when you are done; do not use a broad prune operation.

Details worth checking

• Port keys include the protocol: 80/tcp and 80/udp are different entries.
• Each port maps to a list of PortBinding models, even for one binding.
• HostPort is a string. An empty string requests a daemon-assigned host port; inspect the container after starting it to discover the binding.
• HostIp above binds the published port to the daemon host’s loopback address. It does not refer to the PHP client’s machine when using a remote daemon.
• Bind-mount source paths are on the daemon host, not the PHP client. Docker Desktop may add another host/VM file-sharing boundary.
• Mounting over a container path hides its existing contents. A read-only mount still exposes its files to the container, so do not mount secrets casually.
• Environment entries are NAME=value strings. Do not log sensitive values or treat ordinary container environment variables as a secret store.
• containerCreate() does not pull a missing image. Pull and check the progress stream before creating the container.

An explicit restart policy makes example lifecycle behavior clear. For an application which should retry failed runs, use on-failure and set MaximumRetryCount; do not set that count as a general limit on always or unless-stopped.

For networking beyond port publication, look at NetworkingConfig and its EndpointsConfig map of EndpointSettings models. Keep network attachment and port publication separate; attaching to a network does not expose a port on the host.