nginx-proxy/test/test_http-port/test_http-port.yml

services:
  nginx-proxy:
    environment:
      HTTP_PORT: 8080
    ports:
      - "8080:8080"

  web1:
    image: web
    expose:
      - "81"
    environment:
      WEB_PORTS: "81"
      VIRTUAL_HOST: "*.nginx-proxy.tld"