Docker using .env? about docker-bookstack HOT 2 CLOSED

version: '2'
services:

  mysql:
    image: mysql:5.7.12
    environment:
    - MYSQL_ROOT_PASSWORD=secret
    - MYSQL_DATABASE=bookstack
    - MYSQL_USER=bookstack
    - MYSQL_PASSWORD=secret
    volumes:
    - mysql-data:/var/lib/mysql

  bookstack:
    image: solidnerd/bookstack:0.17.1
    depends_on:
    - mysql
    env_file: .env
    volumes:
    - uploads:/var/www/BookStack/public/uploads
    - storage-uploads:/var/www/BookStack/storage/uploads
    ports:
    - "8080:80"