Dynamically Set object Name

Ionic Framework ionic-v3
1

I have a project and my requirement is I have to set the object name dynamically.

I am using cloud firestore as database…

here is the code :

import { HttpClient } from ‘@angular/common/http’;
import { Injectable } from ‘@angular/core’;
import { AngularFirestore } from ‘angularfire2/firestore’;

@Injectable()
export class FirestoreProvider {

constructor(public http: HttpClient,
public firestore: AngularFirestore) {

}

addCurrency(branchName, currencyName, buyingRate, sellingRate) : Promise{

const id = this.firestore.createId();
 
return this.firestore.doc(`Exchange/${id}`).set({
  id,
  branchName,
  currencyName,
  objectName : {
    buyingRate,
    sellingRate
  }
 
 

});

}

}