Containerize a PHP application

Prerequisites

• You have installed the latest version of Docker Desktop.
• You have a git client. The examples in this section use a command-line based git client, but you can use any client.

Overview

This section walks you through containerizing and running a PHP application.

Get the sample applications

In this guide, you will use a pre-built PHP application. The application uses Composer for library dependency management. You'll serve the application via an Apache web server.

Open a terminal, change directory to a directory that you want to work in, and run the following command to clone the repository.

$ git clone https://github.com/docker/docker-php-sample

The sample application is a basic hello world application and an application that increments a counter in a database. In addition, the application uses PHPUnit for testing.

Initialize Docker assets

Now that you have an application, you can use docker init to create the necessary Docker assets to containerize your application. Inside the docker-php-sample directory, run the docker init command in a terminal. docker init provides some default configuration, but you'll need to answer a few questions about your application. For example, this application uses PHP version 8.2. Refer to the following docker init example and use the same answers for your prompts.

$ docker init
Welcome to the Docker Init CLI!

This utility will walk you through creating the following files with sensible defaults for your project:
  - .dockerignore
  - Dockerfile
  - compose.yaml
  - README.Docker.md

Let's get started!

? What application platform does your project use? PHP with Apache
? What version of PHP do you want to use? 8.2
? What's the relative directory (with a leading .) for your app? ./src
? What local port do you want to use to access your server? 9000

You should now have the following contents in your docker-php-sample directory.

├── docker-php-sample/
│ ├── .git/
│ ├── src/
│ ├── tests/
│ ├── .dockerignore
│ ├── .gitignore
│ ├── compose.yaml
│ ├── composer.json
│ ├── composer.lock
│ ├── Dockerfile
│ ├── README.Docker.md
│ └── README.md

To learn more about the files that docker init added, see the following:

• Dockerfile
• .dockerignore
• compose.yaml

Run the application

Inside the docker-php-sample directory, run the following command in a terminal.

$ docker compose up --build

Open a browser and view the application at http://localhost:9000/hello.php. You should see a simple hello world application.

In the terminal, press ctrl+c to stop the application.

Run the application in the background

You can run the application detached from the terminal by adding the -d option. Inside the docker-php-sample directory, run the following command in a terminal.

$ docker compose up --build -d

Open a browser and view the application at http://localhost:9000/hello.php. You should see a simple hello world application.

In the terminal, run the following command to stop the application.

$ docker compose down

For more information about Compose commands, see the Compose CLI reference.

Summary

In this section, you learned how you can containerize and run a simple PHP application using Docker.

Related information:

• docker init reference

Next steps

In the next section, you'll learn how you can develop your application using Docker containers.