error-handler.intercepter.ts

error-handler.intercepter.ts

import { Injectable } from '@angular/core';
import {
    HttpEvent,
    HttpInterceptor,
    HttpHandler,
    HttpRequest,
    HttpResponse
} from '@angular/common/http';
import { Observable } from 'rxjs';
import { catchError } from 'rxjs/operators';

import { environment } from '@env/environment';
import { Logger } from '../logger.service';
import { AuthenticationService } from '..';
import { Router } from '@angular/router';

const log = new Logger('ErrorHandlerInterceptor');

/**
 * Adds a default error handler to all requests.
 */
@Injectable()
export class ErrorHandlerInterceptor implements HttpInterceptor {
    intercept(
        request: HttpRequest<any>,
        next: HttpHandler
    ): Observable<HttpEvent<any>> {
        return next
            .handle(request)
            .pipe(catchError(error => this.errorHandler(error)));
    }

    // Customize the default error handler here if needed
    private errorHandler(response: HttpEvent<any>): Observable<HttpEvent<any>> {
        if (!environment.production) {
            // Do something with the error
            log.error('Request error');
            log.error(response);
        }
        // unAuthentication
        if (response instanceof HttpResponse) {
            if (response.status === 401) {
                this.authenticationService
                    .logout()
                    .subscribe(() =>
                        this.router.navigate(['/login'], { replaceUrl: true })
                    );
            }
            // swich case with status 500, 404, ...
        }
        throw response;
    }

    constructor(
        private authenticationService: AuthenticationService,
        private router: Router
    ) {}
}