import { Injectable } from '@angular/core'; import { Observable } from 'rxjs/Observable'; @Injectable() export class FbBroadcastServiceMock { broadcast (key: string, data?: any): any { return `Broadcast done. Key: ${key} Data: ${data}`; } on (key: string): T { return Observable.create( observer => { setTimeout(() => { observer.next(key); }, 1); }); } }