php:
    build: ./php
    volumes:
      - ./html/:/var/www/html
    expose:
      - "9000"
    depends_on:
      - mysql
    env_file: .env

<?php var_dump(getenv('MYSQL_DATABASE'));?>

<?php var_dump(getenv('MYSQL_USER'));?>

<?php var_dump(getenv('MYSQL_PASSWORD'));?>

COPY ./test.php /var/www
RUN php /var/www/test.php