docker-compose mysql_pdo connection fail

Question

I have 3 running containers, all is fine (containers are running, database is setted up) except that the PDO connection does not work. There is the error report

    Fatal error: Uncaught PDOException: SQLSTATE[HY000] [2002] Connection 
refused in /var/www/html/lib/OCFram/PDOFactory.php:9 Stack trace: #0 /var/www
/html/lib/OCFram/PDOFactory.php(9): PDO->__construct('mysql:host=mysq...', 
'root', 'root') #1 /var/www/html/lib/OCFram/BackController.php(17): 
OCFram\PDOFactory::getMysqlConnexion() #2 /var/www/html/lib/OCFram
/Application.php(69): OCFram\BackController->__construct(Object(App\Frontend
\FrontendApplication), 'Welcome', 'index') #3 /var/www/html/App/Frontend
/FrontendApplication.php(17): OCFram\Application->getController() #4 /var/www
/html/bootstrap.php(30): App\Frontend\FrontendApplication->run() #5 {main} 
thrown in /var/www/html/lib/OCFram/PDOFactory.php on line 9

the docker-compose.yml

    version: "3.2"
services:
  php:
    build: './php/'
    volumes:
      - ./MediterPourGrandir/:/var/www/html/
  apache:
    build: './apache/'
    depends_on:
      - php
      - mysql
    ports:
      - "8080:80"
    volumes:
      - ./MediterPourGrandir/:/var/www/html/
  mysql:
    image: mysql:5.6.40
    environment:
      - MYSQL_ROOT_PASSWORD=root
      - MYSQL_DATABASE=monsupersite
      - MYSQL_USER=root
      - MYSQL_PASSWORD=root
    ports:
      - "3306:3306"

the php docker file

 FROM php:7.2.7-fpm-alpine3.7
# RUN apk update; \
#   apk upgrade;

# RUN docker-php-ext-install pdo pdo_mysql
# RUN docker-php-ext-install mysqli
RUN apk update --no-cache \
    && apk add --no-cache $PHPIZE_DEPS \
    && apk add --no-cache mysql-dev \
    && docker-php-ext-install pdo pdo_mysql

the pdo connection class

    <?php
namespace OCFram;              

class PDOFactory               
{ 
  public static function getMysqlConnexion()
  { 
    
    $db = new \PDO('mysql:host=mysql;port=3306;dbname=monsupersite', 'root', 'root');
    // $db = new \PDO('mysql:host=mysql;port=3306;charset=utf8', 'root', 'rootpassword');
  
    $db->setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION);
    echo "Connected succesfully";        
        
    return $db;
  }     
}       

I have done so many unsuccessful try. I'am missing something, but can not find out..... If someone got an idea, it would be great.

Thank you.

Answer 1

I finally can find out.

I did not notice it but after few seconds the mysql container were shutting down. The reason is: by default a mysql container name the MYSQL_USER as 'root', so who wants to use 'root' as MYSQL_USER must not declare it. See the github solved issue https://github.com/docker-library/mysql/issues/129

With these settings it works.

mysql:
    image: mysql:5.6.40
    environment:
      - MYSQL_ROOT_PASSWORD=root
      - MYSQL_DATABASE=monsupersite
      - MYSQL_PASSWORD=root
    ports:
      - "3306:3306"

Answer 2

Yes. Or you can check php_info() information does php have enable extension or not.