unauthorized.interceptor.ts

@Injectable()
export class UnauthorizedInterceptor implements HttpInterceptor {
  constructor(private authService: AuthService, private router: Router) {}

  intercept(
    request: HttpRequest<unknown>,
    next: HttpHandler
  ): Observable<HttpEvent<unknown>> {
    return next.handle(request).pipe(
      catchError((err) => {
        if (err.status === 401) {
          this.authService.clearLocalStorage();
          this.router.navigate(['login']);
        }

        if (!environment.production) {
          console.error(err);
        }
        const error = (err && err.error && err.error.message) || err.statusText;
        return throwError(error);
      })
    );
  }
}