I'm working on an Angular Firebase Project, where I need to filter my database as well get the key values. Currently I'm using valueChanges() method in my service code ( inside getUnreadBooks and getFavoriteBooks methods, as shown below ) to get the data and filter it. But it gives me key value as 'undefined', when I try to get key value inside my template file. I tried to go with snapshotChanges() method, but can't work around how to use it to get key values along with filtering the data. Below are my Angular FirebaseService, home.component.ts ( in which I am injecting my service code ) and home.component.html (template file) Code respectively:
import { Injectable } from '@angular/core';
import { AngularFireDatabase } from 'angularfire2/database';
import { Observable } from 'rxjs/Observable';
import 'rxjs/add/operator/map';
@Injectable()
export class FirebaseService {
books: Observable<any[]>;
unreadBooks;
favoriteBooks;
constructor(private db: AngularFireDatabase) {}
getBooks(){
this.books = this.db.list('/books').valueChanges() as Observable<any[]>;
return this.books;
}
getFavoriteBooks(){
this.favoriteBooks = this.db.list('/books').valueChanges() as Observable<any[]>;
this.favoriteBooks = this.favoriteBooks.map(books => {
const topRatedBooks = books.filter(item => item.rate>4);
return topRatedBooks;
})
return this.favoriteBooks;
}
getUnreadBooks(){
this.unreadBooks = this.db.list('/books').valueChanges() as Observable<any[]>;
this.unreadBooks = this.unreadBooks.map(books => {
const ub = books.filter(item => item.dateread == null);
return ub;
})
return this.unreadBooks;
}
}
Home.Component.ts file =>
import { Component, OnInit } from '@angular/core';
import { FirebaseService } from '../../services/firebase.service';
@Component({
selector: 'app-home',
templateUrl: './home.component.html',
styleUrls: ['./home.component.css']
})
export class HomeComponent implements OnInit {
//favorite Books
favoriteBooks: any;
unreadBooks: any;
constructor(private firebaseService: FirebaseService) { }
ngOnInit() {
this.firebaseService.getFavoriteBooks()
.subscribe(favBooks => {
this.favoriteBooks = favBooks;
console.log(this.favoriteBooks);
})
this.firebaseService.getUnreadBooks()
.subscribe(ubBooks => {
this.unreadBooks = ubBooks;
console.log('Unread Books:', this.unreadBooks);
})
}
}
Home.component.html file =>
<mat-toolbar>
My Top Rated Books
</mat-toolbar>
<mat-grid-list cols="3">
<mat-grid-tile *ngFor="let book of favoriteBooks">
<mat-card>
<mat-card-header>
<mat-card-title>
<h4>{{book.title}}</h4>
</mat-card-title>
</mat-card-header>
<img mat-card-image src="{{book.imageUrl}}" alt="{{book.title}}">
<mat-card-actions>
<button mat-button mat-raised-button class="detailsButton" [routerLink]="['/book/'+book.$key]">
<i class="material-icons">visibility</i>Book Details</button>
<button mat-button mat-raised-button class="editButton" [routerLink]="['/editbook/'+book.$key]">
<i class="material-icons">mode_edit</i>Edit Book</button>
</mat-card-actions>
</mat-card>
</mat-grid-tile>
</mat-grid-list>
<mat-toolbar>
Books I have not read yet
</mat-toolbar>
<mat-grid-list cols="3">
<mat-grid-tile *ngFor="let book of unreadBooks">
<mat-card>
<mat-card-header>
<mat-card-title>
<h4>{{book.title}}</h4>
</mat-card-title>
</mat-card-header>
<img mat-card-image src="{{book.imageUrl}}" alt="{{book.title}}">
<mat-card-actions>
<button mat-button mat-raised-button class="detailsButton" [routerLink]="['/book/'+book.$key]">
<i class="material-icons">visibility</i>Book Details</button>
<button mat-button mat-raised-button class="editButton" [routerLink]="['/editbook/'+book.$key]">
<i class="material-icons">mode_edit</i>Edit Book</button>
</mat-card-actions>
</mat-card>
</mat-grid-tile>
</mat-grid-list>
Declare a function to add id to your Object:
documentToDomainObject = _ => {
const object = _.payload.doc.data();
object.id = _.payload.doc.id;
return object;
}
And use it in your getBooks method:
getBooks(){
this.books = this.db.list('/books').snapshotChanges()
.pipe(map(actions => actions.map(this.documentToDomainObject)));
return this.books;
}
In my case I solved it by importing rxjs operator map, combined by.pipe
import { map } from 'rxjs/operators';
Example:
import { Component, OnInit } from '@angular/core';
import { Observable } from 'rxjs';
import { map } from 'rxjs/operators';
import { AngularFirestore } from 'angularfire2/firestore';
import { IdeaService } from './app.service';
import { config } from './app.config';
import { Idea } from './app.model';
import {
AngularFirestoreDocument,
AngularFirestoreCollection
} from 'angularfire2/firestore';
@Component({
selector: 'app-root',
template: `
<ul>
<li *ngFor="let idea of ideas | async">
<pre>{{ idea | json }}</pre>
</li>
</ul>
`
})
export class AppComponent {
public ideasCollection: AngularFirestoreCollection<Idea>;
public ideas: Observable<any[]>;
constructor(db: AngularFirestore, private ideaService: IdeaService) {
this.ideasCollection = db.collection<Idea>(config.collection_endpoint);
this.ideas = this.ideasCollection.snapshotChanges().pipe(
map(actions => {
return actions.map(a => {
const data = a.payload.doc.data() as Idea;
const id = a.payload.doc.id;
return { id, ...data };
});
}));
}
}
You need to import the rxjs operator map import { map } from 'rxjs/operators'; // in rxjs 6 version
I imported this import { map } from 'rxjs/operators'
and this solved my problem
This is with angular 9 and it's working fine.this is set up in the service.ts and get the data from particular.ts file and just normally reader the data into template
getAll() {
return this.database.list('/products').snapshotChanges()
.pipe(map( action => action
.map(a => {
const key = a.payload.key;
const data = a.payload.val();
return data;
})));
}
particular.ts
constructor(private productService: ProductService) {
this.products$ = this.productService.getAll();
}
particular.html
<tr *ngFor="let product of products$ | async" >
<td> {{ product.title }}</td>
<td> {{ product.price }}</td>
this.data.list('/expenseCategories').snapshotChanges().forEach(snapshot=> { snapshot.forEach(keys => { TransactionService.expenseCategories.push(keys.payload.key); }) });
Simple and effective solution: You will get both id and data
Add it in your service file in header part
import { map } from 'rxjs/operators';
your getBooks method:
getBooks(){
return this.books = this.db.list('/books').snapshotChanges()
.pipe(map(action => action
.map(a => {
let obj:any = a.payload.doc.data()
return {
...obj,
id: a.payload.doc.id
};
})
));
}
From the Firebase docs, I see that you cannot get the key when using valueChanges()
, you can only get it when using snapshotChanges()
.
Building on Neelaka's answer, if you're using Angular 12 and the latest version of firebase, if you have a form that uses the (keyup)
event binding you can get the key and also filter like so:
In your product.services.ts
file:
getAll(){
return this.db.list('/products').snapshotChanges().pipe(map(actions => {
return actions.map(a => {
const key = a.payload.key;
const data = a.payload.val();
return {data, key};
})
}));
}
In admin-products.component.ts
file:
export class AdminProductsComponent implements OnDestroy {
products!: { title: string; }[] | any;
filteredProducts!: any[];
subscription: Subscription;
constructor(private productService: ProductService) {
this.subscription = this.productService.getAll().subscribe(products => {
this.filteredProducts = this.products = products;
});
}
filter(query: string){
this.filteredProducts = (query) ?
this.products.filter((p: { data: {title:string}, key: string }) => p.data.title.toLocaleLowerCase().includes(query.toLocaleLowerCase())) :
this.products;
}
ngOnDestroy() {
this.subscription.unsubscribe();
}
}
In admin-products.html
<br>
<p>
<a routerLink="/admin/products/new" class="btn btn-primary">New Product</a>
</p>
<br>
<p>
<input #query (keyup)="filter(query.value)" type="text" class="form-control" placeholder="Search...">
</p>
<br>
<table class="table">
<thead>
<tr>
<th scope="col">Title</th>
<th scope="col">Price</th>
<th scope="col"></th>
<th scope="col"></th>
</tr>
</thead>
<tbody>
<tr *ngFor="let p of filteredProducts">
<td>{{ p.data.title }}</td>
<td>{{ p.data.price }}</td>
<td>
<a [routerLink]="['/admin/products/', p.key]">Edit</a> ✍️
</td>
<td>
<a (click)="delete(p.key)" id="delete">Delete</a> 🗑
</td>
</tr>
</tbody>
</table>
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