How to Dockerize a Basic PHP Application?

Concatly — Thu, 30 May 2019 11:24:41 +0000

What is Docker?

Docker is a tool designed to make it easier to create, deploy, and run applications by using containers. Containers allow a developer to package up an application with all of the parts it needs, such as libraries and other dependencies, and ship it all out as one package.

Steps for Dockerizing a Basic PHP Application

Files required for setup

Create a folder in your working directory.

Add the files given below in the directory.

index.php

This is a basic PHP file which only prints a text on the screen.

<?php

        echo "Hello - This is my first docker application";

?>

Dockerfile

FROM php:7.2-apache
COPY index.php /var/www/html/index.php
EXPOSE 80
CMD ["/usr/sbin/apache2ctl", "-D", "FOREGROUND"]

The base image php:7.2-apache is used. The base image is pulled from dockerhub.
The file index.php is copied to /var/www/html/ in the image.
The port 80 is exposed for apache.
Apache is started inside the container.

Docker Commands

Build an image using docker build command. We build the image with the name phpdemo and tag as v1.

docker build -t phpdemo:v1 .

Run the image in a container using docker run command. We run one container from the image phpdemo:v1. Notice the -p tag. It is used to publish the host port 9090 to the container port 80. In short, if any request will come on port 9090, it will redirect that request to our container in port 80.

docker run -d -p9090:80 phpdemo:v1

Open your browser and go to http://localhost:9090/index.php You should see the output from the PHP file.

Conclusion