feat: create AuthInterceptor and integrate it; adjust AuthGuards accordingly

src/app/app.config.ts

@@ -19,6 +19,7 @@ import { ToastrModule } from 'ngx-toastr';
 import { BrowserAnimationsModule } from '@angular/platform-browser/animations';
 import { HttpErrorInterceptor } from './interceptors/http-interceptor';
 import { HTTP_INTERCEPTORS } from '@angular/common/http';
+import { AuthInterceptor } from './interceptors/auth-interceptor';
 
 export function createTranslateLoader(http: HttpClient) {
   return new TranslateHttpLoader(http, './assets/i18n/', '.json');
@@ -68,5 +69,10 @@ export const appConfig: ApplicationConfig = {
       useClass: HttpErrorInterceptor,
       multi: true,
     },
+    {
+      provide: HTTP_INTERCEPTORS,
+      useClass: AuthInterceptor,
+      multi: true,
+    },
   ],
 };

src/app/components/main-layout/main-layout.component.ts

@@ -1,7 +1,6 @@
 import { Component } from '@angular/core';
 import { RouterOutlet } from '@angular/router';
 import { CommonModule } from '@angular/common';
-
 import { LanguageService } from '../../services/language.service';
 import { SidebarMobileComponent } from '../../shared/components/sidebar/sidebar-mobile/sidebar-mobile.component';
 import { SidebarComponent } from '../../shared/components/sidebar/sidebar.component';

src/app/guards/authenticated.guard.ts

@@ -1,46 +1,33 @@
 import { Injectable } from '@angular/core';
-import { Router } from '@angular/router';
-import { catchError, map, Observable, of } from 'rxjs';
+import { CanActivate, Router } from '@angular/router';
+import { map, Observable } from 'rxjs';
 import { AuthService } from '../services/auth.service';
 import { TokenService } from '../services/token.service';
-import { ToastrService } from 'ngx-toastr';
 import { ToastNotificationService } from '../services/toast-notification.service';
 
 @Injectable({
   providedIn: 'root',
 })
-export class AuthenticatedGuard {
+export class AuthenticatedGuard implements CanActivate {
   constructor(
     private authService: AuthService,
     private tokenService: TokenService,
-    private router: Router,
-    private toastrService: ToastrService,
-    private toastNotificationService: ToastNotificationService
+    private toastNotificationService: ToastNotificationService,
+    private router: Router
   ) {}
 
   canActivate(): Observable<boolean> | Promise<boolean> | boolean {
-    const authToken = this.tokenService.getAuthToken();
-
-    if (!authToken || !this.tokenService.isTokenExpired(authToken)) {
+    if (
+      !this.tokenService.isTokenAvailable() ||
+      !this.tokenService.isUserIdAvailable()
+    ) {
       this.router.navigate(['/login']);
+      this.toastNotificationService.showSessionExpiredToast();
       return false;
     }
 
-    return this.authService.checkAuthUser().pipe(
-      map((isAuthenticated) => {
-        if (isAuthenticated) {
-          return true;
-        } else {
-          this.toastNotificationService.showSessionExpiredMessage();
-          this.router.navigate(['/login']);
-          return false;
-        }
-      }),
-      catchError(() => {
-        this.toastNotificationService.showSessionExpiredMessage();
-        this.router.navigate(['/login']);
-        return of(false);
-      })
-    );
+    return this.authService
+      .checkAuthUser()
+      .pipe(map((isAuthenticated) => isAuthenticated));
   }
 }

src/app/guards/redirect-if-authenticated.guard.ts

@@ -1,14 +1,13 @@
 import { Injectable } from '@angular/core';
-import { Router } from '@angular/router';
-import { Observable, of } from 'rxjs';
-import { map, catchError } from 'rxjs/operators';
+import { CanActivate, Router } from '@angular/router';
+import { Observable, map } from 'rxjs';
 import { AuthService } from '../services/auth.service';
 import { TokenService } from '../services/token.service';
 
 @Injectable({
   providedIn: 'root',
 })
-export class RedirectIfAuthenticatedGuard {
+export class RedirectIfAuthenticatedGuard implements CanActivate {
   constructor(
     private authService: AuthService,
     private tokenService: TokenService,
@@ -16,22 +15,20 @@ export class RedirectIfAuthenticatedGuard {
   ) {}
 
   canActivate(): Observable<boolean> | Promise<boolean> | boolean {
-    const authToken = this.tokenService.getAuthToken();
-
-    if (!authToken || !this.tokenService.isTokenExpired(authToken)) {
+    if (
+      !this.tokenService.isTokenAvailable() ||
+      !this.tokenService.isUserIdAvailable()
+    ) {
       return true;
     }
 
     return this.authService.checkAuthUser().pipe(
       map((isAuthenticated) => {
         if (isAuthenticated) {
+          this.router.navigate(['/summary']);
           return false;
         }
         return true;
-      }),
-      catchError(() => {
-        this.router.navigate(['/login']);
-        return of(false);
       })
     );
   }

src/app/interceptors/auth-interceptor.ts

@@ -0,0 +1,64 @@
+import { Injectable } from '@angular/core';
+import {
+  HttpInterceptor,
+  HttpRequest,
+  HttpHandler,
+  HttpEvent,
+  HttpErrorResponse,
+} from '@angular/common/http';
+import { Observable, throwError } from 'rxjs';
+import { catchError, filter } from 'rxjs/operators';
+import { Router, NavigationStart } from '@angular/router';
+import { TokenService } from '../services/token.service';
+import { ToastNotificationService } from '../services/toast-notification.service';
+
+@Injectable()
+export class AuthInterceptor implements HttpInterceptor {
+  private isNavigatingToLogin = false;
+
+  constructor(
+    private tokenService: TokenService,
+    private router: Router,
+    private toast: ToastNotificationService
+  ) {
+    this.router.events
+      .pipe(
+        filter(
+          (event): event is NavigationStart => event instanceof NavigationStart
+        )
+      )
+      .subscribe((event) => {
+        if (event.url === '/login') {
+          this.isNavigatingToLogin = true;
+        } else {
+          this.isNavigatingToLogin = false;
+        }
+      });
+  }
+
+  intercept(
+    req: HttpRequest<any>,
+    next: HttpHandler
+  ): Observable<HttpEvent<any>> {
+    const token = this.tokenService.getAuthToken();
+    let clonedReq = req;
+
+    if (token) {
+      clonedReq = req.clone({
+        setHeaders: {
+          Authorization: `Token ${token}`,
+        },
+      });
+    }
+
+    return next.handle(clonedReq).pipe(
+      catchError((error: HttpErrorResponse) => {
+        if (error.status === 401 && !this.isNavigatingToLogin) {
+          this.toast.showSessionExpiredToast();
+          this.router.navigate(['/login']);
+        }
+        return throwError(() => error);
+      })
+    );
+  }
+}

src/app/services/toast-notification.service.ts

@@ -43,7 +43,7 @@ export class ToastNotificationService {
     );
   }
 
-  showSessionExpiredMessage(): void {
+  showSessionExpiredToast(): void {
     this.createInfoToast(
       'Your session has expired, please log in again.',
       'Session Expired'

src/app/services/token.service.ts

@@ -43,14 +43,11 @@ export class TokenService {
     sessionStorage.removeItem(this.USER_ID_KEY);
   }
 
-  isTokenExpired(token: string): boolean {
-    try {
-      const payload = JSON.parse(atob(token.split('.')[1]));
-      const expiry = payload.exp;
-      if (!expiry) return true;
-      return expiry * 1000 < Date.now();
-    } catch (e) {
-      return true;
+  isTokenAvailable(): boolean {
+    return !!this.getAuthToken();
   }
+
+  isUserIdAvailable(): boolean {
+    return !!this.getUserId();
   }
 }