yadi

Yet Another Dependency Injection library

yadi is a simple and small dependency injection library. yadi can inject dependencies using constructor injection and property injection

Installation

Installing yadi is easy like running

$ npm install @begad/yadi reflect-metadata --save
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or

$ yarn add @begad/yadi reflect-metadata
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You will need a transpiler that supports decorators

To enable decorator support in typescript, add "experimentalDecorators": true in your tsconfig.json like:

{
	// ...
	"compilerOptions": {
		// ...
		"experimentalDecorators": true
		// ...
	}
	// ...
}
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yadi also requires support for Map. If you need to support a JavaScript engine that doesn't support Map, you will need to import a polyfill.

Usage

Import reflect-metadata and yadi in your entry point like:

// src/index.ts
import "reflect-metadata";
import { Container, inject } from "yadi";
// ...
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Create a new container:

const container = new Container();
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Optional: Add a new namespace:

container.addNamespace("papers");
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Bind dependencies:

// If using property injection
class VeryTallPaper {
	@inject()
	private ruler: Ruler;
	get height() {
		return this.ruler.measure();
	}
}
// Or if using constructor injection
class VeryTallPaper {
	public constructor(@inject("ruler") private ruler: Ruler) {}
	get height() {
		return this.ruler.measure();
	}
}
class Ruler {
	public measure() {
		return 10;
	}
}
container.bind("ruler").toClass(Ruler);
container
	.bind("verytallpaper") // or container.bind("verytallpaper", "papers") if using namespaces
	.toClass(VeryTallPaper);
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Resolve it!

const paper = container.resolve("verytallpaper"); // or container.resolve("papers:verytallpaper") if using namespaces
paper.height; // 10
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If you don't want to inject everything into the container use the create method of container like:

container.unbind("verytallpaper"); // Or don't bind it at all
const paper = container.create(VeryTallPaper);
paper.height; // 10
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API Docs

The API docs is available at https://begad666.github.io/yadi