I want to receive data from the realtime database in firebase. The Data is shown below:

The code I tried is

return this.db.list('messages', ref => {
  return ref.limitToLast(25).orderByKey();
});

but it's not working

I want to receive data from the realtime database in firebase. The Data is shown below:

The code I tried is

return this.db.list('messages', ref => {
  return ref.limitToLast(25).orderByKey();
});

but it's not working

• javascript
• angular
• firebase
• firebase-realtime-database
• angularfire2

2 Answers 2

Try this to get the messages list from the firestore. Import AngularFireDatabase service and AngularFireList to store message collection.

import { Injectable } from '@angular/core';
import { AngularFireDatabase, AngularFireList } from '@angular/fire/database';

@Injectable({
  providedIn: 'root'
})
export class MessageService {
  
    messages: AngularFireList<any>;
  
   constructor(private http: HttpClient, private db: AngularFireDatabase) { }

   /**
     * Get All tickers from firebase
     */
    getMessages(): Observable<any> {
      this.messages = this.db.list('messages');
      return this.messages.valueChanges();
    }

}

Make sure you have imported AngularFireModule and AngularFireDatabaseModule in your app module.

AngularFire is build with the Observable Pattern via RxJs Library.

You can stream the data with the valueChanges() method, as described in the documentation

items: Observable<any[]>;
constructor(firestore: AngularFirestore) {
   this.items = firestore.collection('items').valueChanges();
}