Ionic capacitor push notification using capacitor plugin and angular fire

app.component.ts

import { Component } from '@angular/core';

import { FcmProvider } from './providers/core/fcm';
import { GlobalsProvider } from './providers/core/globals';
import { environment } from 'src/environments/environment.prod';

@Component({
  selector: 'app-root',
  templateUrl: 'app.component.html',
  styleUrls: ['app.component.scss']
})
export class AppComponent implements AfterViewInit {

  constructor(
    private fcm: FcmProvider,
    private _deeplinkservice: DeeplinkService,
    public globals: GlobalsProvider,
  ) {
    this.initializeApp();
  }

  private initializeApp() {
    this.globals.platform.ready()
    .then(() => {
      this.pushNotification();
    }).catch((err: any) => {
      console.log("App platform running error", err)
    })
  }

  private pushNotification() {
    try { 
      this.fcm.ngOnInit();
      this.fcm.getPushNotification()
      .then((data:any) => {
        // alert(data)
        this.globals.showLocalNotification({
          schedule: {at: new Date(new Date().getTime())},
          title: data.title,
          body: data.message,
          id: 1
        });
      }).catch((ex: any) => {
        throw ex
      })
    } catch (ex) {
      console.error('Error with Push plugin ' + JSON.stringify(ex));
    }
  }
}

fcm.ts

import { Injectable, OnInit } from '@angular/core';
import {
  Plugins,
  PushNotification,
  PushNotificationToken,
  PushNotificationActionPerformed } from '@capacitor/core';
import { GlobalsProvider } from './globals';
import { environment } from 'src/environments/environment.prod';
import { AngularFireMessaging } from '@angular/fire/messaging';
declare var $: any;
const { PushNotifications } = Plugins;

@Injectable({
  providedIn: 'root'
})
export class FcmProvider implements OnInit
{
  devices: Array<any> = [];
  constructor(
    private firemsg: AngularFireMessaging,
    private globals: GlobalsProvider,
  ){
  }

  async ngOnInit() {
    let result: any;
    if(this.globals.platform.is('capacitor')) {
      result = await PushNotifications.requestPermission();
    } else {
      this.firemsg.requestPermission.subscribe((res: any) => {
        console.log(res);
      })
    }
    if (result && result['granted']) {
      PushNotifications.register();
      const token: any = await this.getToken();
      const response: any = await this.saveToken(token);
      console.log(response);
    } else {
      console.log("Push notification error on register", result);
    }
  }

  async saveToken(token: string) {
    return await new Promise((resolve, reject) => {
      // alert(token);
      resolve(token);
    })
  }

  subscribeToChannel(name: string) {

  }

  unsubscribeFromChannel(name: string) {

  }

  private async getToken() {
    return await new Promise((resolve, reject) => {
      try {
        // On success, we should be able to receive notifications
        if(this.globals.platform.is('capacitor')) {
          PushNotifications.addListener('registration',
            (token: PushNotificationToken) => {
              resolve(token.value);
            }
          );
        } else {
          this.firemsg.getToken.subscribe((token: any) => {
            console.log(token);
            resolve(token);
          })
        }
      }catch(ex) {
        reject(ex);
      }
    })
  }

  async sendingPushNotification(fcm: string, title: string, msg: any, extra: any = null, page: any) {
    return await new Promise((resolve, reject) => {
      page = encodeURI(`${environment.deeplink_url}${page}`);
      $.ajax({        
        type : 'POST',
        url : "https://fcm.googleapis.com/fcm/send",
        headers : {
            Authorization : 'key=' + 'AAAAGnd2Nsg:APA91bFQyaAEa6SsDycc8UyJ5h1UVbcyDLcZ4pv3M40XryofpQC3d7Y1vLhKBIwyevk7ashZbZIWAQJWArvVF8sfNRXD4rqAI0ABVSwsufa7oIzsCVFPJAidEOs8KFSg_6DQy4uBqgeh'
        },
        contentType : 'application/json',
        dataType: 'json',
        data: JSON.stringify(
          {
            "to": fcm, 
            "notification": {
              "title": title,
              "extra": extra,
              "click_action": page,
              "body": msg
            }
          }
        ),
        success : function(response) {
          if(response.success == 1){
            resolve(response);
          } else {
            reject(response);
          }
        },
        error : function(xhr, status, error) {
          reject(xhr.error);          
        }
      });
    })
  }

  async getPushNotification() {
    return await new Promise((resolve, reject) => {
      try {
        if(this.globals.platform.is('capacitor')) {
          PushNotifications.addListener('pushNotificationReceived',
            (notification: PushNotification) => {
              resolve(notification);
            }
          );
          PushNotifications.addListener('pushNotificationActionPerformed',
            (notification: PushNotificationActionPerformed) => {
              resolve(notification);
            }
          );
        } else {
          // web push
          this.firemsg.messages.subscribe(
            (payload) => {
              console.log(payload);
              resolve(payload);
          })
        }
      } catch(ex) {
        if(this.globals.platform.is('capacitor')) {
          PushNotifications.addListener('registrationError',
            (error: any) => {
              reject('Error on registration: ' + JSON.stringify(error));
            }
          );
        } else {
          reject('Error on registration: ' + JSON.stringify(ex));
        }
      }
    })
  }
}