Docker compose for custom Wordpress image and MySQL database

docker-compose.yml

version: '3.1'

services:

  wp:
    container_name: wordpress
    build: .
    ports:
      - 8080:80
    restart: always
    environment:
      IS_DOCKER: 'true'
      WORDPRESS_DB_HOST: db
      WORDPRESS_DB_USER: user1
      WORDPRESS_DB_PASSWORD: password1
      WORDPRESS_DB_NAME: database1
      WORDPRESS_TABLE_PREFIX: wp_
    depends_on:
      - db
    links:
      - db:mysql
    volumes:
      - ./public:/var/www/html
      - ./env:/mnt/env

  db:
    container_name: mysql
    image: mysql:5.7
    restart: always
    ports:
      - "3307:3306"
    environment:
      MYSQL_DATABASE: database1
      MYSQL_USER: user1
      MYSQL_PASSWORD: password1
      MYSQL_ROOT_PASSWORD: letmein
    volumes:
      - ./db:/var/lib/mysql

volumes:
  wordpress:
  db: