Using Firebase Timestamp with Angular Bootstrap’s Datepicker

Idan Cohen
Dec 21, 2018 · 2 min read

Firestore, the cloud database service by Google’s Firebase, recently announced that dates stored in its documents will be retrieved by default as Timestamps.

Timestamp is a javascript object with two properties: seconds and nanoseconds. It also comes with a few helpful methods: fromDate(), toDate() and now().

This change requires quite a few adjustments in the way your app handles dates. One of which is the implementations of Angular Bootstrap’s Datepicker. Luckily, ng-bootstrap offers a very convenient adapter to handle conversion between any custom date, and the ng-bootstrap’s native date structure.

To implement this adapter, create a new file called ngb-date-firestore-adapter.service.ts -

import { Injectable } from '@angular/core';
import { NgbDateAdapter, NgbDateStruct } from '@ng-bootstrap/ng-bootstrap';
import { firestore } from 'firebase';

* NgbDateAdapter implementation that allows using Firebase Firestore TimeStamp as a user date model.
export class NgbDateFirestoreAdapter extends NgbDateAdapter<firestore.Timestamp> {
* Converts Firestore TimeStamp to a NgbDateStruct

fromModel(ts: firestore.Timestamp): NgbDateStruct {
if (ts instanceof firestore.Timestamp) {
return {
year: ts.toDate().getFullYear(),
month: ts.toDate().getMonth() + 1,
day: ts.toDate().getDate()
} else return null;

* Converts a NgbDateStruct to a Firestore TimeStamp
toModel(ngbDate: NgbDateStruct): firestore.Timestamp {
const jsDate = new Date(
ngbDate.year ? ngbDate.year : new Date().getFullYear(),
ngbDate.month ? ngbDate.month - 1 : new Date().getMonth() - 1, ? : new Date().getDate(),
return firestore.Timestamp.fromDate(jsDate);


Then edit you app.module (or wherever you import NgbModule into your project) and add add this line your modules provider array -

providers: [
{ provide: NgbDateAdapter, useClass: NgbDateFirestoreAdapter }

Now you can attach any Timestamp property to a Datepicker field.

Check full demo -

Any questions? Corrections? Please comment… :-)

Idan Cohen

Written by

Client Architect @ UVeye

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