Adding async validation support in ngModel | angular

Learn about how angular forms package manage your asynchronous validation through ngModel directive. In this video, we will deep dive into the angular forms and learn every bit of asynchronous validation directives as below

How to define an async validation directive?
What is the use of NG_ASYNC_VALIDATORS DI token?
How ngModel inject async validation directives?
Adding support for async validation into the AbstractControl class and
some code optimizations.

Checkout complete series - Build your own angular forms package

Complete code

Time codes:
00:00:00 - Introduction to asynchronous validation
00:03:50 - Define AsyncValidator interface
00:06:40 - Define asynchronous validation directive
00:08:57 - Register validation directive on NG_ASYNC_VALIDATORS DI token
00:10:46 - Inject async validation directives into ngModel
00:18:06 - Compose async validator function
00:29:33 - Update AbstractControl class to handle async validation
00:38:12 - Test and fix code errors
00:43:29 - Code refactoring