Exploring the Power of Angular 5: Implementing httpClient Interceptors

Question

Exploring the Power of Angular 5: Implementing httpClient Interceptors

I'm looking to understand how to incorporate the httpClient interceptor in this brief example, leveraging Angular5.

import { Observable }     from 'rxjs/Observable';
import {HttpClient, HttpHeaders} from '@angular/common/http';

//service
logintest(): Observable<any>{
    var body = {
      "username": "<a href="/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="3b5a59587b5a595815585456">[email protected]</a>",
      "password": "Passw0rd",
    }
    let headers = new HttpHeaders().set('Content-Type','application/x-www-form-urlencoded; charset=utf-8;');

    return this.http.post("http://restapiUrl/v1/loginservice", body, {headers: headers});
}

Appreciate your help on this matter. Best regards, Andrea.

angular typescript

Answer 1

Answer №1

If you're looking for guidance, consider the following example.

Begin by Creating a .TS File

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

import { Observable } from 'rxjs/Observable';
import 'rxjs/add/operator/do';

@Injectable()
export class MyCustomInterceptor implements HttpInterceptor {
  intercept(
    req: HttpRequest<any>,
    next: HttpHandler
  ): Observable<HttpEvent<any>> {

    return next.handle(req).do(evt => {
      if (evt instanceof HttpResponse) {
        console.log('---> status:', evt.status);
        console.log('---> filter:', req.params.get('filter'));
      }
    });

  }
}

To set up our interceptor, provide it in either the app module or a feature module using the HTTP_INTERCEPTORS token:

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';

import { HttpClientModule, HTTP_INTERCEPTORS } from '@angular/common/http';
import { MyCustomInterceptor } from './interceptors/my.custom.interceptor';


@NgModule({
  declarations: [AppComponent],
  imports: [BrowserModule, HttpClientModule],
  providers: [
    { provide: HTTP_INTERCEPTORS, useClass: MyCustomInterceptor, multi: true }
  ],
  bootstrap: [AppComponent]
})
export class AppModule {}

Answer 2

If you're looking for guidance, consider the following example.

Begin by Creating a .TS File

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

import { Observable } from 'rxjs/Observable';
import 'rxjs/add/operator/do';

@Injectable()
export class MyCustomInterceptor implements HttpInterceptor {
  intercept(
    req: HttpRequest<any>,
    next: HttpHandler
  ): Observable<HttpEvent<any>> {

    return next.handle(req).do(evt => {
      if (evt instanceof HttpResponse) {
        console.log('---> status:', evt.status);
        console.log('---> filter:', req.params.get('filter'));
      }
    });

  }
}

To set up our interceptor, provide it in either the app module or a feature module using the HTTP_INTERCEPTORS token:

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';

import { HttpClientModule, HTTP_INTERCEPTORS } from '@angular/common/http';
import { MyCustomInterceptor } from './interceptors/my.custom.interceptor';


@NgModule({
  declarations: [AppComponent],
  imports: [BrowserModule, HttpClientModule],
  providers: [
    { provide: HTTP_INTERCEPTORS, useClass: MyCustomInterceptor, multi: true }
  ],
  bootstrap: [AppComponent]
})
export class AppModule {}

Answer 3

Answer №2

To successfully utilize HttpInterceptor, it is necessary to create a new class called AppInterceptor and redefine the intercept method as shown below:

export class AppInterceptor implements HttpInterceptor {

 constructor(){
 }

 intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
 }
}

Answer 4

To successfully utilize HttpInterceptor, it is necessary to create a new class called AppInterceptor and redefine the intercept method as shown below:

export class AppInterceptor implements HttpInterceptor {

 constructor(){
 }

 intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
 }
}

Exploring the Power of Angular 5: Implementing httpClient Interceptors

Answer №1

Answer №2

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