Project Description

This repository is a playground for a many powerful NestJS architectural concepts & patterns used in some of today's most complex Node.js systems in the real-world.

Topics covered so far:

• layered (N-tier) architecture
• hexagonal architecture in practice #1 #dee7a18
• hexagonal architecture in practice #2 #8870700

  • ^ #8870700 is a simple application that allows to create and fetch alarms, but this application is much more than that. Infrastructure was decoupled from the application layer using the modules composition pattern. Now we can simply switch between different infrastructure implementation without having to change the application layer itself. In this particular case we simply switch between an in-memory database and a Postgres database via TypeORM.

• experimenting with CQRS #1 #590a7b0
• experimenting with CQRS #2 #a3c0349
• experimenting with CQRS #3 #55d7ed1

  • ^ #55d7ed1 this is really huge PR, but we've implemented the READ side of the CQRS pattern using MongoDB, so now application uses two different data stores (PostgreSQL for WRITE and MongoDB for READ). Upon receiving an event, system automatically creates a denormalized alarm view and stores it in the READ side database.

  • docker-compose down --remove-orphans & docker-compose up -d
  • curl --location --request POST 'localhost:3000/alarms' \ --header 'Content-Type: application/json' \ --data-raw '{ "name": "Alarm 1", "severity": "HIGH", "triggeredAt": "2021-01-01T00:00:00.000Z", "items": [{ "name": "Item 1", "type": "TYPE_1" }, { "name": "Item 2", "type": "TYPE_2" }] }' | json_pp
  • curl http://localhost:3000/alarms | json_pp
• implementing Event Store #1 #d5a905b
  • docker-compose up -d event-store
• implementing Event Store #2 #3d7e2fa
• autowire event classes #e6752bd
• rehydrating aggregates #a050a74
• more to come...

Project Graph [Modules]

Project setup

$ pnpm install

Deployment

Check out Mau, official platform for deploying NestJS applications on AWS.

Resources

Check out a few resources that may come in handy when working with NestJS:

• Visit the NestJS Documentation to learn more about the framework.
• Deploy your application to AWS with the help of NestJS Mau in just a few clicks.
• Visualize your application graph and interact with the NestJS application in real-time using NestJS Devtools.

License

Nest is MIT licensed.