Registry

Are you tired of creating a thousand factory files?

Are you a lazy programmer (won't judge you tbh) and just want to do your thing and let the computer do the rest?

Are you tired of having to manually register your dependencies?

Your problems are now over

Description

Registry is a simple library that enable you to register and resolve dependencies automatically either via class or token.

Installation

$ npm install --save @lakshamana/registry

Usage

// Animal.ts
import { Injectable, InjectVariable } from '@/core/decorators'

@Injectable()  // make sure to add this decorator to the classes you want to make injectable
export class Animal {
  @InjectVariable() animalName: string  // make sure you have set `ANIMAL_NAME` in your env variables

  @InjectVariable('SPECIES_NAME') species: string  // you can use a custom env variable name, instead

  get tag (): string {
    return `${this.animalName}: [species=${this.species}]`
  }

  eat (): void {
    console.log(`${this.tag} is eating`)
  }
}

// Bone.ts
export interface Canidae {
  walk: () => void
  eat: () => void
  getAnimal: () => Animal
}

@Injectable()
export class Bone {
  @Inject('dog') dog: Canidae  // inject instance via token, useful to work with interfaces

  printOwner (): void {
    console.log(`[owner]: ${this.dog.getAnimal().tag}`)
  }
}

// main.ts
const registry = Container.getRegistry()  // get a registry singleton

registry.register([
  Animal,             // pass your classes to the registry
  Bone,
  {                   // pass your instances using a token and a provider factory
    provide: 'dog',
    useFactory: () => new Dog(new Animal())
  },
  {                   // you can pass your instances as a class as well
    provide: 'cat',
    useClass: Cat
  }
])

// You can also get manually the instances from the registry
const animal = registry.get(Animal)
animal.eat()  // <animalName>: [species=<species>] is eating

Notice that, if you're running TypeScript 5.x you may want to declare class properties from inside receiver constructor, like this:

class Class {
  constructor(
    @Inject() private readonly instance: AnotherInstance  // if you annotated `AnotherInstance` with `@Injectable()`
  ) {}

  method () {
    // this.instance should be available here
  }
}

API

Brief API and type definitions description

Container

This will (wait for it...) contain the registry as a singleton object to be used through your application

• static getRegistry (): Registry
  • Gets/creates and returns a registry singleton

Registry

• register (dependencies: Array<Constructor | Provider>): Registry
  • Registers the providers into the registry
• get<T extends Constructor>(target: T | string): InstanceType<T>
  • Retrieves a dependency from the registry by class or token string

Decorators

This will help you to make your classes injectable, inject your variables or instances

• @Injectable(): class decorator
  • Use it to annotate the classes you need to be injectable
• @Inject(token: string): property decorator
  • Use it to annotate class properties you need instances to be injected to
• @InjectVariable(key?: string): property decorator
  • Use it to annotate class properties you need variables to be injected to

Running examples from source code

Clone this repository, then run:

$ npm install
$ cp .env.example .env
$ npm run dev

Testing

$ npm test
$ npm run test:watch
$ npm run test:ci  # check coverage
$ npm run test:staged

Contributing

Feel free to open issue and open PRs with due tests, and I'll check as soon as I can.

Notice that this project is using Semantic Versioning and Conventional Commits for versioning and commit message pattern respectively, so make sure to follow it. PRs that don't follow these patterns or don't have tests may be rejected.