TypeORM Polymorphism (feature)

The goal of this repository is to develop Polymorphism feature for TypeORM.

Starting Point

The first iterestion is directly from the answer to: https://stackoverflow.com/questions/52995280/typeorm-polymorphic-relations on stack exchange.

Road-map

• Version 0.1 | most basic realization of polymorphism:
  • morphOne() : polymorphism from inside the same table
• Version 0.2 | most advance realization of polymorphism:
  • morphToMany() : polymorphism with a separate joint table
• Version 1.0 | creating full set of features:
  • morphOne()
  • morphMany() : morphOne but with possibility for more than one association
  • morphTO() : reverse of morphOne and morphMany
  • morphToMany()
  • morphByMany() : reverse of morphToMany

Collaboration Guide

• read doc-laravel-eloquent.md to get on the same page about what functionalities we are trying to implement.

Why

developers migrating from ActiveRecord (ruby) and Laravel Eloquent (PHP) who use Polymorphism in their model architectures are disparate for such a feature!

Answering Frequent Counter-Argument

There are some programmers who are vehemently against "polymorphism" because this level of functionalities break away from the standard built-in feature shipped by standard Relational databases. However, this functionality is nothing unusual for graph based databases.

So, though some wish to bran it as "anti-pattern", in reality, ORM-s are not meant to be married with relational databases, and the reason we use this pattern is as a temporary measure till graph based databases become more mature, more wide-spread and etc.

While it is fine to avoid a feature/design such a polymorphic relationships between the models in your app/library, just because open-source relational databases don't ship a foreign-key constraint check by default for graph-like patterns, doesn't mean graph-like patterns are sins!