Firebase Phone Auth using Ionic V3 - Sending and reading OTP

FirebasePhoneAuthIonicV3.md

General Steps to be followed as a flow process to complete Firebase Phone OTP Auth in Ionic V3

Step 1 : Get the phone number through input from the user. Step 2 : Pass this phone number to the firebase and receive a callback with verification ID. Step 3 : Pass on this verification ID through navParams to the next page where the user will enter the OTP sent to the entered mobile number. Step 4 : Verify the OTP that is sent with firebase for success() or failure() .

STEP 1 & 2 & 3

phone-verification.html

<ion-content padding>
  <div class="img_container">
    <img src="assets/img/web_logo.png">
  </div>
  <div id="recaptcha-container"></div>
  
  <div class="img_container">
    <img src="assets/img/web_text.png">
  </div>
  <h2> Let's get to know you better </h2>
  <ion-item class="input_item">
    <ion-input type="number" placeholder="Mobile number (Ex: +91xxxxxxxxxx)" [(ngModel)]="phoneNumber" ></ion-input>
  </ion-item>
</ion-content>
<ion-footer no-shadow>
	<button ion-button color="app_color" block class="btn_login" (click)='signIn(phoneNumber)'>PROCEED</button>
</ion-footer>

phone-verification.ts

import { ApiProvider } from './../../providers/api/api';
import { Component } from '@angular/core';
import { IonicPage, NavParams, AlertController, NavController } from 'ionic-angular';
import firebase from 'firebase';
import {Firebase} from '@ionic-native/firebase';

@IonicPage()
@Component({
  selector: 'page-phone-verification',
  templateUrl: 'phone-verification.html',
})
export class PhoneVerificationPage {
  public recaptchaVerifier: firebase.auth.RecaptchaVerifier;
  verificationId: any = '';
  phoneNumber: any = '';
  countryCode: any = '';
  result: any;
  constructor(public navCtrl: NavController,private api: ApiProvider, public navParams: NavParams, private alertCtrl: AlertController,public firebase: Firebase) {
  }
  
  ionViewDidLoad() {
    this.recaptchaVerifier = new firebase.auth.RecaptchaVerifier('recaptcha-container'); 
    console.log('ionViewDidLoad PhoneVerificationPage');
  }

  OtpScreen() {
    this.countryCode = '+' + this.phoneNumber.substring(0, 2);
    this.phoneNumber = this.phoneNumber.substring(2, 13);
    console.log(this.countryCode, this.phoneNumber); 
  }


  signIn(phoneNumber: number) { //Step 2 - Pass the mobile number for verification
    this.api.presentLoader('Sending OTP to your mobile number');
    let number =this.phoneNumber;
    (<any>window).FirebasePlugin.verifyPhoneNumber(number, 60, (credential) =>{
    console.log(credential);
    this.api.dismissLoader();
    var verificationId = credential.verificationId;
    this.navCtrl.push('OtpPage',{verificationid: verificationId}); //This is STEP 3 - passing verification ID to OTP Page
    }, (error) =>{
      //this.eer = error;
      this.api.dismissLoader();
      this.api.presentToast('Failed to send OTP. Try again');
      console.error(error);
    });
  }
}

STEP 4

Otp.html

<ion-content padding>
  <div class="img_container">
    <img src="assets/img/web_logo.png">
  </div>
  <div class="typography_container">
    <img src="assets/img/web_text.png">
  </div>
  <h3>Type the OTP sent your mobile</h3>
  <div class="otp_container">
   
    <ion-item>
      <ion-input type="text" placeholder="Enter OTP sent to your mobile" [(ngModel)]="otp"></ion-input>
    </ion-item>
  </div>
</ion-content>

<ion-footer no-shadow>
    <button ion-button color="app_color" block class="btn_login" (click)='roleSelection()'>PROCEED</button>
</ion-footer>

Otp.ts

import { ApiProvider } from './../../providers/api/api';
import { Component } from '@angular/core';
import { IonicPage, NavController, NavParams } from 'ionic-angular';
import firebase from 'firebase';
import { Firebase } from '@ionic-native/firebase';


@IonicPage()
@Component({
  selector: 'page-otp',
  templateUrl: 'otp.html',
})
export class OtpPage {
  verification_id: any;
  otp:string='';
  constructor(public navCtrl: NavController, private api: ApiProvider,public navParams: NavParams) {
    this.verification_id = this.navParams.get('verificationid');
  }

  ionViewDidLoad() {
    console.log('ionViewDidLoad OtpPage');
  }

  roleSelection() {
    this.api.presentLoader('Verifying your OTP');
    var signInCredential = firebase.auth.PhoneAuthProvider.credential(this.verification_id,this.otp);
    firebase.auth().signInWithCredential(signInCredential).then(()=>{    
      console.log(signInCredential);
      setTimeout(()=>{
        this.api.dismissLoader();
        this.api.presentToast('OTP Verified');
      },2000);
      this.navCtrl.setRoot('RoleSelectionPage');
    }).catch(()=>{
      this.api.dismissLoader();
      this.api.presentSimplesAlert('OTP Failed','Failed to verify OTP');
      console.log('Erorr in OTP');
    });
    
  }
}

Thats it ! Implement and let me know your feedbacks in the comment below. I would be happy to resolve your queries if any.

I wonder why they give this project 10 stars? The codes are incomplete. Where is apiProvider class? Without it the codes are useless.

Where is the api file?

is your code working on Ionic version 4+ project ?

No I am using Ionic 3.9.2 version