Introduction

Ths is the first post in a 2 part series, where I explore how to setup a dockerised RabbitMQ instance with MQTT support and outline how we can use RabbitMQ and its MQTT plugin to talk to devices with MQTT and AMQP in a polyglot manner.

Part two can be found here:
- The Internet of things, with RabbitMQ, Node.js, MQTT and AMQP

Source code can be found here:
- the-internet-of-things-rabbitmq-mqtt

MQTT is a machine-to-machine connectivity protocol, used by many to support the 'Internet of Things'. It was designed as an extremely lightweight publish/subscribe messaging transport. RabbitMQ supports MQTT via plugin.

In this post

• An MQTT enabled RabbitMQ docker image
• Enable RabbitMQ ports on a mac for docker
• Run RabbitMQ with docker-compose
• RabbitMQ management console
• Docker exposed environment variables

An MQTT enabled RabbitMQ docker image

I have created a docker image with MQTT enabled: andrewkeig/rabbitmq-mqtt-enabled, which is simply the official RabbitMQ docker image 3.5 as base, with MQTT and Management plugins enabled.

FROM rabbitmq:3.5.0

RUN rabbitmq-plugins enable --offline rabbitmq_management
RUN rabbitmq-plugins enable --offline rabbitmq_mqtt

EXPOSE 15672
EXPOSE 1883

Enable RabbitMQ ports on a mac for docker

If you are running on a mac, run the following commands to forward ports.

$ VBoxManage modifyvm "boot2docker-vm" --natpf1 "rb1,tcp,127.0.0.1,1883,,1883"
$ VBoxManage modifyvm "boot2docker-vm" --natpf1 "rb2,tcp,127.0.0.1,15672,,15672"
$ VBoxManage modifyvm "boot2docker-vm" --natpf1 "rb3,tcp,127.0.0.1,5672,,5672"

Run RabbitMQ with docker-compose

In order to run the docker image you can use the following docker-compose file, which uses the image I created with MQTT enabled. We expose 3 ports:

• Management plugin : 15672
• AMQP: 5672
• MQTT: 1883

    rb:
      image: andrewkeig/rabbitmq-mqtt-enabled
      volumes:
        - /var/docker/rabbit:data
      ports:
        - "15672:15672"
        - "5672:5672"
        - "1883:1883"

Now we have our docker-compose file setup we can simply run:

$ docker-compose up

RabbitMQ management console

If you would like to view the RabbitMQ management console; this can be found here:

http://localhost:15672

• username: guest
• password: guest

Docker exposed environment variables

If you would like to use this image as part of your project, Docker exposes two RabbitMQ environment variables. We have to do a bit of url hacking in order to change the protocol contained in the docker url.

var mqttUrl = process.env.RB_PORT_1883_TCP.replace('tcp', 'mqtt');
var amqpUrl = process.env.RB_PORT_5672_TCP.replace('tcp', 'amqp');