You have two option here -
- HttpInterceptor
auth.service.ts
If you are writing any standard application which require credential validation now or later then you will need AuthService
. However you can ignore right now if you want.
// src/app/auth/auth.service.ts
import { Injectable } from '@angular/core';
import decode from 'jwt-decode';
@Injectable()
export class AuthService {
public getToken(): string {
return localStorage.getItem('token');
}
public isAuthenticated(): boolean {
// get the token
const token = this.getToken();
// return a boolean reflecting
// whether or not the token is expired
return tokenNotExpired(null, token);
}
}
app.module.ts
Provide HTTP_INTERCEPTORS
which will intercept all request of yours.
// src/app/app.module.ts
import { HTTP_INTERCEPTORS } from '@angular/common/http';
import { TokenInterceptor } from './../auth/token.interceptor';
@NgModule({
bootstrap: [AppComponent],
imports: [...],
providers: [
{
provide: HTTP_INTERCEPTORS,
useClass: TokenInterceptor,
multi: true
}
]
})
export class AppModule {}
token.interceptor.ts
This is Interceptor through which each HTTP request will pass through.
// src/app/auth/token.interceptor.ts
import { Injectable } from '@angular/core';
import {
HttpRequest,
HttpHandler,
HttpEvent,
HttpInterceptor
} from '@angular/common/http';
import { AuthService } from './auth/auth.service';
import { Observable } from 'rxjs/Observable';
@Injectable()
export class TokenInterceptor implements HttpInterceptor {
constructor(public auth: AuthService) {}
intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
request = request.clone({
setHeaders: {
Authorization: `Bearer ${this.auth.getToken()}`
}
});
return next.handle(request);
}
}
- Overwrite the standard HttpClient
app.module.ts
@NgModule({
providers: [ // expose our Services and Providers into Angular's dependency injection
{provide: HttpClient, useClass: ExtendedHttpService},
]
})
export class AppModule {
}
extended-http.service.ts
import {Injectable, Injector} from '@angular/core';
import {Request, XHRBackend, RequestOptions, Response, Http, RequestOptionsArgs, Headers} from '@angular/http';
import {Observable} from 'rxjs/Observable';
import {Router} from '@angular/router';
import {AuthService} from './auth.service';
import 'rxjs/add/operator/catch';
import 'rxjs/add/observable/throw';
@Injectable()
export class ExtendedHttpService extends HttpClient {
private router: Router;
private authService: AuthService;
constructor(backend: XHRBackend, defaultOptions: RequestOptions, private injector: Injector) {
super(backend, defaultOptions);
}
request(url: string | Request, options?: RequestOptionsArgs): Observable<Response> {
if (typeof url === 'string') {
if (!options) {
options = {headers: new Headers()};
}
this.setHeaders(options);
} else {
this.setHeaders(url);
}
//console.log("url: " , url , ", Options:" , options);
return super.request(url, options).catch(this.catchErrors());
}
private catchErrors() {
return (res: Response) => {
if (this.router == null) {
this.router = this.injector.get(Router);
}
if (res.status === 401 || res.status === 403) {
//handle authorization errors
//in this example I am navigating to login.
console.log("Error_Token_Expired: redirecting to login.");
this.authService.logout();
}
return Observable.throw(res);
};
}
private setHeaders(objectToSetHeadersTo: Request | RequestOptionsArgs) {
if (this.authService == null) {
this.authService = this.injector.get(AuthService);
}
//add whatever header that you need to every request
//in this example I could set the header token by using authService that I've created
objectToSetHeadersTo.headers.set('Authorization', this.authService.getAuthToken());
}
}