Demo app for Event Sourcing architecture

Demo application to demonstrate the power of the event sourcing architecture for DevelopersBR livestream

You can check that in JavaScript as well

Summary

• Demo app for Event Sourcing architecture
  • Summary
  • What is event sourcing
    • Related material
  • Running the application
  • Useful tooling
  • Challenge!
    • How do I improve?

What is event sourcing

Event sourcing is a development pattern to solve audit problems and make our application more easily maintainable. It is described as:

A way to capture all changes to an application state as a sequence of events.

There's not much jabber about it right now, however this pattern first emerged in one of Martin Fowler's articles in 2005, for some reason it's been forgotten ever since.

I'm not describing it all here, however I have a series of related material (in portuguese) so you can study it for yourself.

Related material

• What is event sourcing (talk in portuguese)
• Let's talk about event sourcing and how it can save your project (in portuguese)
• An architecture guide to use event sourcing
• Livestream video where I build this application (in portuguese)
• Slides used in this livestream
• Article about this architecture
• Video about this architecture (2021) [Portuguese]

Running the application

This app uses Docker Compose as runner, it'll build and set all your containers, you just need to run docker-compose up in the root directory.

Useful tooling

• Doctor
• Tardis - A Nodejs library to control time
• Paradox - A Nodejs library to aid event sourcing apps

Challenge!

This app version has some intentional "errors" and/or misleading designs in order to incentivate students to improve it.

How do I improve?

Our branches are named master which is v1, we have v2 with some additional improvements. If you want to make even more improvements, clone the project and go to the v2 branch. Then do your thing and submit a PR for approval.

DO NOT FORGET TO ADD WHAT YOU HAVE CHANGED IN THE BACKEND CHANGELOG OR FRONTEND CHANGELOG FILES IN ORDER TO LET PEOPLE KNOW WHAT HAS BEEN DONE

PR's without changelogs will not be approved