docker-projects/docker-compose-proxy.yml

version: "3"
services:
    app:
        image: app:debian
        build: app
        expose:
            - "5000"
        ports:
            - "5000:5000"
        networks:
          webnet:
            aliases:
                - app

    webserver:
        image: websrv:proxy
        build: webserver
        expose:
            - "80"
        ports:
            - "80:80"
        networks:
          webnet:
            aliases:
                - www
        depends_on:
            - app

networks:
  webnet: