interceptor error handling angular 9

1import { HttpEvent, HttpInterceptor, HttpHandler, HttpRequest, HttpErrorResponse } from '@angular/common/http';
2import { Observable, throwError } from 'rxjs';
3import { catchError } from 'rxjs/operators';
4export class HttpErrorInterceptor implements HttpInterceptor {
5  intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
6    return next.handle(request)
7      .pipe(
8        catchError((error: HttpErrorResponse) => {
9          let errorMsg = '';
10          if (error.error instanceof ErrorEvent) {
11            console.log('this is client side error');
12            errorMsg = `Error: ${error.error.message}`;
13          }
14          else {
15            console.log('this is server side error');
16            errorMsg = `Error Code: ${error.status},  Message: ${error.message}`;
17          }
18          console.log(errorMsg);
19          return throwError(errorMsg);
20        })
21      )
22  }
23}

1// src/app/auth/jwt.interceptor.ts
2
3// ...
4import 'rxjs/add/operator/do';
5
6export class JwtInterceptor implements HttpInterceptor {
7
8  constructor(public auth: AuthService) {}
9
10  intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
11    
12    return next.handle(req).do((event: HttpEvent<any>) => {
13      if (event instanceof HttpResponse) {
14        // do stuff with response if you want
15      }
16    }, (err: any) => {
17      if (err instanceof HttpErrorResponse {
18        if (err.status === 401) {
19          // redirect to the login route
20          // or show a modal
21        }
22      }
23    });
24  }
25}
26