Angular2 DI in Typescript. Can we use it in node.js / non-angular projects?

Question

Was the angular2 dependency injection container designed for standalone use, and is it possible to use it for typescript/javascript server-side applications ?

I open

Answer 1

As of Angular 2 RC.5, DI is a part of @angular/core package. For non-Angular uses, it was recently extracted into injection-js package by Minko Gechev, a member of Angular team.

Here is a short ES6, Node-friendly example:

// may not be needed for injection-js and recent @angular/core versions
// if ES5-flavoured `Class` helper isn't used
require('reflect-metadata');

const { Inject, Injector, ReflectiveInjector, OpaqueToken } = require('@angular/core');
// or ... = require('injection-js');

const bread = new OpaqueToken;
const cutlet = new OpaqueToken;

class Sandwich {
    constructor(bread, cutlet, injector) {
        const anotherBread = injector.get('bread');

        injector === rootInjector;
        bread === 'bread';
        anotherBread === 'bread';
        cutlet === 'cutlet';
    }
}

Sandwich.parameters = [
    new Inject(bread),
    new Inject(cutlet),
    new Inject(Injector)
];

const rootInjector = ReflectiveInjector.resolveAndCreate([
    { provide: 'bread', useValue: 'bread' },
    { provide: bread, useValue: 'bread' },
    { provide: cutlet, useValue: 'cutlet' },
    Sandwich
]);

const sandwich = rootInjector.get(Sandwich);