Add auth guard

Closes #7

src/app/app.module.ts

@@ -3,6 +3,7 @@ import { BrowserModule } from '@angular/platform-browser';
 import { RouteReuseStrategy } from '@angular/router';
 import { IonicModule, IonicRouteStrategy } from '@ionic/angular';
 import { AngularFireModule } from '@angular/fire';
+import { AngularFireAuthModule } from '@angular/fire/auth';
 
 import { AppRoutingModule } from './app-routing.module';
 import { AppComponent } from './app.component';
@@ -15,6 +16,7 @@ import { environment } from '../environments/environment';
     BrowserModule,
     AngularFireModule.initializeApp(environment.firebaseConfig),
     IonicModule.forRoot(),
+    AngularFireAuthModule,
     AppRoutingModule
   ],
   providers: [{ provide: RouteReuseStrategy, useClass: IonicRouteStrategy }],

src/app/auth/auth.page.html

@@ -4,4 +4,8 @@
   </ion-toolbar>
 </ion-header>
 
-<ion-content> </ion-content>
+<ion-content>
+  <ion-button routerLink="/tabs/map" expand="block">
+    Close
+  </ion-button>
+</ion-content>

src/app/shared/auth.guard.ts

@@ -0,0 +1,27 @@
+import { Injectable } from '@angular/core';
+import { CanLoad, Route, UrlSegment, Router } from '@angular/router';
+import { AngularFireAuth } from '@angular/fire/auth';
+import { Observable } from 'rxjs';
+import { take, map, tap } from 'rxjs/operators';
+
+@Injectable({
+  providedIn: 'root'
+})
+export class AuthGuard implements CanLoad {
+  constructor(private authService: AngularFireAuth, private router: Router) {}
+
+  canLoad(
+    route: Route,
+    segments: UrlSegment[]
+  ): boolean | Observable<boolean> | Promise<boolean> {
+    return this.authService.authState.pipe(
+      take(1),
+      map(user => !!user),
+      tap(isAuhtenticated => {
+        if (!isAuhtenticated) {
+          this.router.navigate(['/auth']);
+        }
+      })
+    );
+  }
+}

src/app/tabs/tabs-routing.module.ts

@@ -2,6 +2,7 @@ import { NgModule } from '@angular/core';
 import { RouterModule, Routes } from '@angular/router';
 
 import { TabsPage } from './tabs.page';
+import { AuthGuard } from '../shared/auth.guard';
 
 const routes: Routes = [
   {
@@ -31,7 +32,8 @@ const routes: Routes = [
         children: [
           {
             path: '',
-            loadChildren: '../settings/settings.module#SettingsPageModule'
+            loadChildren: '../settings/settings.module#SettingsPageModule',
+            canLoad: [AuthGuard]
           }
         ]
       },