Angular / Raspberry / AngularFire demo code

import { Component } from '@angular/core';
import { AngularFireAuth } from '@angular/fire/compat/auth';
import { AngularFireDatabase } from '@angular/fire/compat/database';
import { Observable, of, iif, switchMap, timer } from 'rxjs';

const URL_IMAGE = 'IMAGE PATH;

interface MyData {
  ble: {
    temp: number;
    pressure: number;
    altitude: number;
  }
}

@Component({
  selector: 'fb-demo-firebase',
  template: `
      <ng-template #showLogin>
        <h1 class="title-xl">Firebase Demo</h1>
        <button (click)="login()" class="btn btn-outline-secondary">
          <i class="fa fa-sign-in me-2"></i>Login with Google
        </button>
      </ng-template>

      <div *ngIf="auth.user | async as user; else showLogin">
        <h1 class="title-xl mt-5">
          <i class="fa fa-user"></i>
          Hello {{ user.email | json }}!
        </h1>

        <div class="row">
          <div *ngIf="data$ | async as data" class="col">
            <h1 class="title-xl mt-5">
              <i class="fa fa-thermometer-2"></i>
              {{data.ble.temp | number: '1.2-2'}} °
            </h1>

            <h1 class="title-xl mt-5">
              <i class="fa fa-arrows-v"></i>
              {{data.ble.altitude | number: '1.2-2'}} cm
            </h1>

          </div>

          <div class="col">
            <img [src]="url" alt="WebCam" width="100%" style="border-radius: 20px">
          </div>
        </div>

        <button (click)="logout()" class="btn btn-outline-secondary">
          <i class="fa fa-sign-out"></i>
          Logout
        </button>
      </div>
  `,
})
export class DemoFirebaseComponent {
  data$: Observable<MyData | null> = this.auth.user
    .pipe(
      switchMap(res => iif(
          () => !!res,
          this.db.object<MyData>(res.uid).valueChanges(),
          of(null)
      ))
    )
  url = URL_IMAGE;

  constructor(
    public auth: AngularFireAuth,
    private db: AngularFireDatabase,
  ) {
    timer(0, 1000)
      .subscribe(() => this.url = URL_IMAGE + Math.random())
  }

  login() {
    this.auth.signInWithEmailAndPassword('biondi@biondi.com', 'biondi')
  }
  logout() {
    this.auth.signOut();
  }
}