docker compose sample

docker-compose.yml

version: '2'
services:
  db:
    image: gordlea/postgis:9.5
    environment:
     - POSTGRES_DB=myapp_api_development
     - POSTGRES_USER=root

  dbtest:
    image: gordlea/postgis:9.5
    environment:
     - POSTGRES_DB=myapp_api_test
     - POSTGRES_USER=root

  web:
    build: .
    command: bin/rails s --port 3000 --binding 0.0.0.0
    volumes:
      - .:/app
    ports:
      - "3000:3000"
    links:
      - db
      - dbtest