Rachel Orti and Melanie Rao on migrating a legacy monolith to a scalable SaaS application

17-07-2018 Antonio Goncalves 0 all

Hi Rachel and Melanie, tell us who you are and what lead you into microservices?

Hi, I’m Rachel Orti. I am a Tech Lead working for the IBM Software Lab in France and very happy to also still contribute as a developer. I am not born in the cloud like Melanie 🙂 I started to work on the development of enterprise applications in .NET/Java/JEE years ago. I really love to learn new stuff. That’s how I moved to the Cloud effort three years ago. I have recently contributed to the birth of IBM Operational Decision Manager (aka ODM) on IBM Cloud Private, from writing the first Docker files to packaging the Helm charts. And we will be very happy to share our experience with Melanie at Voxxed Days Microservices.

Hi, I’m Melanie Rao. I am a Software Engineer who joined IBM in the south of England almost five years ago. I immediately landed in the cloud and microservices world by joining a team in charge of deploying a SaaS version of their product. In 2016, I decided to move back to France, and joined another cloud team within IBM based in Paris. I have been part of IBM ODM’s journey to the cloud since then, focusing on deploying and maintaining the ODM on Cloud SaaS offering using Docker, Kubernetes, and Helm. It is proving to be a very exciting adventure that I am looking forward to speak to you about!

What will you be talking about at Voxxed Days Microservices?

We had a massive legacy monolith application based on Java Web applications (IBM ODM) that we wanted to launch into the cloud. At Voxxed Days Microservices, we will discuss our journey as developers, from learning what a Docker container is to creating easily configurable and scalable Helm charts leveraging the full power of Kubernetes. For each step, we will share with you what we have learned (both technically and culturally), the do’s and don’ts and the biggest challenges we faced (including how to develop and test).

When you migrated from a monolith to a scalable application, did you just focus on external technical parts (Kubernetes, Docker, Helm…) or did you also have to touch the business code, the datastore, etc.? What were the challenges?

Initially our aim was to split and repackage ODM into containers without touching the business code. We were rapidly able to deploy a simple topology with our Java Web applications running in application servers packaged in Docker containers but we soon realized that parts of our business code were too static. We had to allow to configure our product on the fly without needing to fiddle inside the containers. We realized notably that changing certain configurations was not taken into account everywhere without restarting the application server. We had to change the Java code to make the configuration more dynamic and this allowed us to improve our product in general, whether on the cloud or on premise. It was a really good opportunity to put ourselves in the shoes of people operating and using our product!