In this app, I wanted to toy with the complications of managing many-to-many relationships with a NoSQL database such as Mongo and a Reactive environment such as Reactor.
Create a Contract for one or more Property s which are owned by one or more Client s who need money from one or MadBanker s. But then figure it this way:
- a Property (like a shopping mall) may need a couple of Contracts to handle the building and the parking lot
- But then, one might need a report on a particular
Clientwho has a numberContracts with their attendantPropertys andMadBankerobligations.
BankingAgg is an aggregation in the Entity or Model layer which helps to create associations between the Entities.
Most of the data work is handled in the Service layer. That was easy to handle and view with tools like MongoDB Compass and Atlas. However the simple attachment of a Property to a Contract didn't show up when viewing the transaction with a WebClient or a tool like Postman. That only worked when 'destucturing' the zipped set of Tuples (through Mono.zip() or Flux.zip()) with the TupleUtils.function() method. That method, based on a @FunctionalInterface provided a learning experience in itself.
In the Controller layer, I utilized the regular @RestController as well as RouterFunction<ServerResponse> implementations with associated Handlers. Not all the simple CRUD operations are set up on the Controller layer. The CRUD ops are on the Service layer. I'll fix 'em later.
In the application.properties file, you'll find the following among other items:
spring.profiles.active=classic
# spring.profiles.active=data
When first starting the app comment out the "...active = classic" and uncomment the "...active=data" like so:
# spring.profiles.active=classic
spring.profiles.active=data
That will load up your MongoDB with some data. (Don't forget to 'reset' spring.profiles.active)
spring.profiles.active=classic
The basics of the project are:
- Project type: Maven
- Language: Java
- Spring Boot version :2.7.3
- Project Metadata/Java: 17
- Dependencies: Reactive Web
- And make sure you have Lombok installed