Functional Programming Application Framework

Inspiration

• Railway Oriented Programming. Result (either) (neverthrow)
• Clean Architecture, ports and adapters
• Rich Domain Model
• Persistence Ignorant Domain
• Command/Query Handlers
• Domain Events (and Integration Events)
• Screaming Architecture
• Domain Driven Design
• Dependency Injection (IoC), but lightweight, just enough to manage some lifecycles (singleton and scoped)

Usage

Run Sample

• yarn
• yarn start

Run compile/lint/test

• yarn testsuite

Access over http://localhost:3535/train-trip see TrainTrip.router.ts for paths and methods, and router-schema.json for a complete picture.

Thoughts

• Authentication (for whole router [DONE], for just a route, opt-in or opt-out)
  • Based on command/query metadata or is it infrastructure concern?
  • BasicAuth
  • future: OAuth based
• Authorization
• Keep up with Typescript improvements for Generic inference etc.

After stabilization

• Enhance container to prevent dependency capturing (ie a singleton that 'captures' a transient or scoped dependency)
• Remove "opinionation"
  • Make it easy to use any validation framework
• Look into performance signatures and identify areas that need improvement

Additional usecase samples

• Soft delete

Resources

• https://fsharpforfunandprofit.com/posts/against-railway-oriented-programming/
• https://fsharpforfunandprofit.com/ddd/
• https://fsharpforfunandprofit.com/rop/
• https://github.com/gcanti/fp-ts
• https://dev.to/_gdelgado/type-safe-error-handling-in-typescript-1p4n
• https://khalilstemmler.com/articles/enterprise-typescript-nodejs/handling-errors-result-class/
  • & more: https://khalilstemmler.com/articles
• SimpleInjector
• MediatR Request/Event handlers and Pipelines.
• https://github.com/tc39/proposal-pipeline-operator/wiki