docker-compose.yml

version: '3'
services:
  web:
    image: apache
    build: ./webapp
    container_name: apache
    restart: always
    # we can see the server running at "localhost:8080"
    ports:
      - "8080:80"

  e2e:
    image: cypress
    build: ./e2e
    container_name: cypress
    depends_on:
      - web
    # note: inside e2e container, the network allows accessing
    # "web" host under name "web"
    # so "curl http://web" would return whatever the webserver
    # in the "web" container is cooking
    # see https://docs.docker.com/compose/networking/
    environment:
      - CYPRESS_baseUrl=http://web
    command: npx cypress run
    # mount the host directory e2e/cypress and the file e2e/cypress.json as
    # volumes within the container
    # this means that:
    #  1. anything that Cypress writes to these folders (e.g., screenshots,
    #     videos) appears also on the Docker host's filesystem
    #  2. any change that the developer applies to Cypress files on the host
    #     machine immediately takes effect within the e2e container (no docker
    #     rebuild required).
    volumes:
      - ./e2e/cypress:/app/cypress
      - ./e2e/cypress.json:/app/cypress.json