Varnish docker-compose.yml file that defines container dependencies

docker-compose.yml

version: '3'
services:
  echo-server:
    image: "jmalloc/echo-server:latest"
    container_name: origin
    hostname: origin
    ports:
     - "8080:8080"
  varnish:
    image: "varnish:latest"
    container_name: varnish
    hostname: varnish
    volumes:
      -  ./config/default.vcl:/etc/varnish/default.vcl
    ports:
      - "80:80"
    depends_on:
      - "origin"