docker-compose.yml

version: '2'
services:
  php:
     image: phpmyadmin/phpmyadmin
     links:
       - mysql:db
     depends_on:
       - mysql

  mysql:
    image: k0st/alpine-mariadb
    volumes:
      - ./data/mysql:/var/lib/mysql
    environment:
      - MYSQL_DATABASE=mydb
      - MYSQL_USER=myuser
      - MYSQL_PASSWORD=mypass 

  nginx:
    image: nginx:stable-alpine
    ports:
      - "81:80"
    volumes:
      - ./nginx/log:/var/log/nginx
      - ./nginx/nginx.conf:/etc/nginx/nginx.conf:ro
    depends_on:
      - php

nginx/nginx.conf

worker_processes  1;
events {
  worker_connections  1024;
}
http {
  sendfile  off;
  server {
    listen 80;
 
    location / {
      proxy_pass  http://php;
      proxy_set_header Host $host;
      proxy_redirect     off;
    }
  }
}

Note the nginx config is simplified but above should work for testing — basically all it’s doing is proxying the php app. Maps to port 81 to avoid conflicts on the host - adjust as needed.

Regarding linking, you can see that if you run: docker-compose exec mysql ping -c2 nginx to ping from the mysql container to the nginx container, you will succeed even though there are no links specified between these containers. Docker Compose will maintain those links in the default network for you.