In this lesson we are going to use AngularFire 2 for the first time. We are going to configure the AngularFire 2 module, inject the AngularFire service in our service layer and use it do our first Firebase query: we are going to retrieve a list of objects from the database.

Install:

//install 

npm install --save angularfire2

Import AngularFireModule in app.module.ts:

...
import {firebaseConfig} from "../environments/firebase.config";
import {AngularFireModule} from "angularfire2"; @NgModule({
...
imports: [
...
AngularFireModule.initializeApp(firebaseConfig)
],

Load the data in service: realtime.service.ts:

import { Injectable } from '@angular/core';
import {AngularFire, FirebaseListObservable} from "angularfire2"; @Injectable()
export class RealtimeService { constructor(private af: AngularFire) {
const courses$: FirebaseListObservable<any> = af.database.list('courses');
courses$.subscribe(
val => console.log("val", JSON.stringify(val, null, ))
)
} }

firebase database.list() method return 'FirebaseListObservable' type.

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