Meetesh's Blog | PHP and MySQL on Docker

PHP and MySQL on Docker

Hello All, welcome to my first blog.

Let's check how can we run the legacy php and mysql combo on any platform using docker.

If you are new to docker check resources on their official website here or check their docker 101 playlist here.

Now, Assuming you have docker installed on your machine let's start.

We will first create a hello world project in php, for that:

Create a folder let's say : hello-php
Create a file : index.php

Write the below code in that file and save it:

<?php
    echo "Hello world! from docker";
?>

Create a new file in the same folder called: docker-compose.yml and put the below content :

version: "3.8"
services:
web:
    image: php:7.4.10-alpine
    volumes:
    - .:/code
    ports:
    - "8000:8000"
    command: php -S 0.0.0.0:8000 -t /code

Run the below command ( it will download the php image )
```
docker-compose up
```
You should see something like this after the download finishes:
Server starts at localhost:8000. Now simply navigate to http://localhost:8000 on your browser and you'll see this:

Now let's connect to mysql db :

Add mysql and adminer images in your existing docker-compose.yml it should look like this:

version: "3.8"
services:
  web:
    image: php:7.4.10-alpine
    volumes:
      - .:/code
    ports:
      - "8000:8000"
    command: php -S 0.0.0.0:8000 -t /code
  db:
    image: mysql:5.6
    command: --default-authentication-plugin=mysql_native_password
    environment: 
      MYSQL_ROOT_PASSWORD: secret_1
  adminer:
    image: adminer
    ports:
      - "8081:8080"

Run the same docker-compose command this time with option -d

docker-compose up -d

You won't see any logs now, since -d tells docker-compose to run it as detached mode.

Navigate to browser and open localhost:8081

you should see adminer login page:

Try login with username: root and password: secret_1 and you should be able to login.

Now that we have php and mysql up and running, let's connect our hello-php application with the mysql db.

To be able to run php with mysql we need to download mysql extension for php. Follow the below steps:

Create a directory say php-with-mysql cd php-with-mysql

Create a file named Dockerfile write the below code

FROM php:7.4-alpine
RUN docker-php-ext-install pdo_mysql

run : docker build -t php-with-mysql:7.4.10-alpine . It will create a new image on your local system with tag 7.4.10-alpine, we'll use this image in our docker-compose.yml

Now let's update our docker-compose.yml file it should look like below:

version: "3.8"
services:
  web:
    image: php-with-mysql:7.4.10-alpine
    container_name: hello-web
    volumes:
      - .:/code
    ports:
      - "8000:8000"
    command: php -S 0.0.0.0:8000 -t /code
  db:
    image: mysql:5.6
    container_name: hello-db
    command: --default-authentication-plugin=mysql_native_password
    environment: 
      MYSQL_ROOT_PASSWORD: secret_1
      MYSQL_DATABASE: hellodb
      MYSQL_USER: hello_user
      MYSQL_PASSOWRD: hello_password
  adminer:
    image: adminer
    ports:
      - "8081:8080"

Now let's connect our php file with this database, for that you need to add below code:

<?php
echo "Connecting...<br />";
try
{
    $databaseServerName='hello-db';
    $databaseName='hellodb';
    $databaseUsername='hello-user';
    $databasePassword='hello-pass';
    $c=new PDO("mysql:host=$databaseServerName;dbname=$databaseName",$databaseUsername,$databasePassword);
    $c->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);
    echo "Connection successful\n";
}catch(Exception $e)
{
    echo $e;
} 
?>

This is simple PDO code to establish a connection with mysql db.

Now we need to do some clean up of our existing container before we update the containers.

This is required because mysql won't get updated with the new values provided unless we stop and remove the existing container.

run docker ps
copy the name/id of the container running mysql
run docker stop <name/id>
run docker rm <name/id>

Now we are ready to update the containers with updated yaml file.

run docker-compose up -d

Navigate to http://localhost:8000

Connection successful shown

Now we learned how to create a Docker image locally, Run a db with a web server using docker compose, and some php PDO.

Let me konw your feedbacks and questions here.

Thanks!