docker-compose.yml

# Docker Compose description of the combined application.
#
# 'docker-compose up' will run this.
version: '3'  # requires Docker Compose 1.13 or later

# This section describes the various containers (services).
services:
  
  rabbitmq:
    # There is a prebuilt RabbitMQ image; see
    # https://hub.docker.com/_/rabbitmq/ for details.
    # This variant is built on Alpine Linux (it's smaller) and includes
    # the management UI.
    image: 'rabbitmq:3.6-management-alpine'

    # These ports are exposed on the host; 'hostport:containerport'.
    # You could connect to this server from outside with the *host's*
    # DNS name or IP address and port 5672 (the left-hand side of the
    # colon).
    ports:
      # The standard AMQP protocol port
      - '5672:5672'
      # HTTP management UI
      - '15672:15672'

    # Run this container on a private network for this application.
    # This is necessary for magic Docker DNS to work: other containers
    # also running on this network will see a host name "rabbitmq"
    # (the name of this section) and the internal port 5672, even though
    # that's not explicitly published above.
    networks:
      - network

  consumer:
    # If needed, Docker Compose will automatically run consumer/Dockerfile.
    build: consumer

    # Environment variables:
    environment:
      # The location of the RabbitMQ server.  "amqp" is the protocol;
      # "rabbitmq" is the hostname.  Note that there is not a guarantee
      # that the server will start first!  Telling the pika client library
      # to try multiple times gets around this ordering issue.
      AMQP_URL: 'amqp://rabbitmq?connection_attempts=5&retry_delay=5'

    # Again, run on the private network.  Needed to see the "rabbitmq"
    # magic Docker DNS name.
    networks:
      - network

  publisher:
    # Identical to the consumer.
    build: publisher
    environment:
      AMQP_URL: 'amqp://rabbitmq?connection_attempts=5&retry_delay=5'
    networks:
      - network

networks:
  # Declare our private network.  We must declare one for the magic
  # Docker DNS to work, but otherwise its default settings are fine.
  network: {}