连接到 docker-compose 中的 mysql

Question

I am using docker-compose version 1.21.0.

I've made the docker-compose.yml:

  container_name: web
  image: nginx:latest
  ports:
    - "80:80"
  volumes:
    - ./code:/code
    - ./nginx.conf:/etc/nginx/conf.d/default.conf
  links:
    - php
    - mysql

php:
  container_name: php
  build: .
  volumes:
    - ./code:/code
  environment:
    XDEBUG_CONFIG: remote_host=host.docker.internal
  links:
    - mysql

mysql:
  container_name: mysql
  image: mysql:latest
  ports:
    - "3306:3306"
  volumes:
    - ./storage-mysql:/var/lib/mysql
    - ./conf-mysql:/etc/mysql/conf.d
  environment:
    - MYSQL_ROOT_PASSWORD=passwordz

All is fine, I can access my mysql db with:

docker exec -it mysql mysql -u root -p

Note, I have setup my mysql DB with:

bind-address            = 127.0.0.1

Because I do not want to expose mysql to internet.

And I have made a simple form with PHP:

<?php

$link = mysqli_connect("mysql:3306", "root", "passwordz", "testdb");

if($link === false){
    die("ERROR: Could not connect. " . mysqli_connect_error());
}


$icao = mysqli_real_escape_string($link, $_REQUEST['icao']);
$airfield = mysqli_real_escape_string($link, $_REQUEST['airfield']);
$lati = mysqli_real_escape_string($link, $_REQUEST['lati']);


$sql = "INSERT INTO testdb (icao, airfield, lati) VALUES ('$icao', '$airfield', '$lati')";
if(mysqli_query($link, $sql)){
    echo "Records added successfully.";
} else{
    echo "ERROR: Could not able to execute $sql. " . mysqli_error($link);
}


mysqli_close($link);
?>

But with many try with differents configuration, I have the http error message after the post:

Warning: mysqli_connect(): (HY000/2002): Connection refused in /code/insert.php on line 4

Did I miss something? I am totaly lost and really need help.

Regards,

Answer 1

In Docker you almost always need to set bind-address and similar options to 0.0.0.0 ("everywhere"), or else the server won't be reachable from outside its own container.

You can add an IP address to ports: to attach the published port to a specific host interface:

services:
  mysql:
    ports:
      # This binds the published port to the _host's_ localhost
      # interface; it will be reachable from outside Docker on
      # the same host, but not from other hosts
      - '127.0.0.1:3306:3306'

If you don't need the database to be accessible from outside Docker, you can also remove the ports: section entirely. It will still be reachable from other containers using its Compose service name and the standard MySQL port ( mysql:3306 ).