Building a simple service relay for Dynamics 365 CE with RabbitMQ and Python

In my last post in this series, I outlined an approach for building a simple service relay with RabbitMQ and Python to easily expose an on-premises Dynamics 365 Customer Engagement organization to external consumers. In this post I will walk through the prerequisites for building this out. I'm assuming you have access to a Dynamics 365 CE organization, so I'm going to skip the setup for that and focus on just RabbitMQ and Python today.

Setting up RabbitMQ

Back in 2015 When I first blogged about RabbitMQ and Dynamics 365, I wrote a detailed post showing how to install and configure RabbitMQ. Since then I have discovered the joys of Docker, which makes the process significantly easier. If you have access to Docker, I highly recommend using it. Once you have Docker running, you can use one of the official RabbitMQ images. For this project, I initially used the rabbitmq:3-management image in Docker for Windows running on my local PC. After I got the basic functionality working, I then moved to an instance of Docker running in the cloud on a Digital Ocean VPS.

If don't want to use Docker, you can use a full RabbitMQ install like I showed previously. The main thing to remember is that no matter how you set up your RabbitMQ server, if it is not accessible from the public internet, you will not be able to use it as a service relay between an on-premises Dynamics 365 org and external consumers.

Setting up Python

I'm assuming if you've gotten this far, you have a functional Python development environment (if not, give Visual Studio Code a try), and the code I have written works in Python versions 2.7 or 3.x. In order to connect to both RabbitMQ and Dynamics 365, you will need a few additional packages. To connect to RabbitMQ, Pika is the RabbitMQ team's recommended Python client, and you can get it using pip.

To communicate with Dynamics 365, you'll need to use the Web API, but authentication will be handled differently depending on whether you connect to an on-premises org or an online / IFD org. For online or IFD orgs, you can either use ADAL or this alternate approach I described back in 2016. If you have an on-premises org, you can authenticate using the requests_ntlm package like I showed here. As with the Pika client, all the packages you need to connect to Dynamics 365 are also available via pip.

Wrapping up

That's it for today. In my next post in this series I will show the Python code you need to make this service relay work.