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PHP + MySQL using Docker Compose

Aly Sivji on February 27, 2018

This post was originally published on Siv Scripts Being a Software Engineer isn't just about being effective in a specific programming language, i...

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Richard Orelup • Feb 27 '18 • Edited

Thanks for the article. While trying to run through the above I ran into this error

ERROR: In file './docker-compose.yml', service must be a mapping, not a NoneType.

which I solved by updating docker-compose.yml to this

version: '3'

services:
  db:
    image: mysql:5.7
    environment:
      MYSQL_ROOT_PASSWORD: my_secret_pw_shh
      MYSQL_DATABASE: test_db
      MYSQL_USER: devuser
      MYSQL_PASSWORD: devpass
    ports:
      - "9906:3306"
  web:
    image: php:7.2.2-apache
    container_name: php_web
    depends_on:
      - db
    volumes:
      - ./php/:/var/www/html/
    ports:
      - "8100:80"
    stdin_open: true
    tty: true

The indentation matters and this finally got it working. Hope this helps anyone else trying to use this.

Aly Sivji • Feb 27 '18

Thanks for the heads up!

Didn't realize the indentation got messed up as I copied this over. It has been corrected.

Richard Orelup • Feb 27 '18

I'm just getting in to Docker so I'm actually glad it had that issue so I'm now aware that I have to get the indentation correct. :)

Vladimir Efremenko • Feb 27 '22

When working with the database from the application, I get the following:
Fatal error: Uncaught Error: Call to undefined function mysqli_connect() in /var/www/html/index.php:6 Stack trace: #0 {main} thrown in /var/www/html/index.php on line 6

Connection code:
<?php
$servername = "localhost:9906";
$username = "devuser";
$password = "devpass";
$dbname = "test_db";
$conn = mysqli_connect($servername, $username, $password, $dbname) or die("Fatal error: " . mysqli_connect_error());
if (mysqli_connect_errno()) {
printf("Fatal error: %s\n", mysqli_connect_error());
exit();
}
?>

With the help of mysqlworkbench i can connect and work with the database!
Tell me where I went wrong and why it doesn't work?

Gonzalo Valenzuela • Mar 1 '18

Thanks, Aly. I have a question: if the container is restarted, are the MySQL databases lost? In other words, is there persistence in the database?

Aly Sivji • Mar 1 '18 • Edited

The setup I describe above stores data inside of the container. This data is lost when the container is deleted (docker-compose down)

You could mount a volume so the data is persisted on your local machine.

Looking at hub.docker.com/_/mysql/ (search for Where to Store Data), we can update the docker-compose.yml with another volume mount as follows:

# ./docker-compose.yml

version: '3'

services:
  db:
    image: mysql:5.7
    environment:
      MYSQL_ROOT_PASSWORD: my_secret_pw_shh
      MYSQL_DATABASE: test_db
      MYSQL_USER: devuser
      MYSQL_PASSWORD: devpass
    volumes:
      - ./sql:/var/lib/mysql
    ports:
      - "9906:3306"
  web:
    image: php:7.2.2-apache
    container_name: php_web
    depends_on:
      - db
    volumes:
      - ./php/:/var/www/html/
    ports:
      - "8100:80"
    stdin_open: true
    tty: true

Now data will persist in the ./sql directory.

Gonzalo Valenzuela • Mar 1 '18

Thank you very much!