Set the server port for sending API requests from Angular to NodeJS in development

Issue

I have this MEAN Stack application and for the front-end I'm using Angular 6, I created the users rooting and back-end login system and I've tested it using Postman and it works as expected. but when I use the form I always get this error below:

I know the problem is to change the port from 4200 to 3000 but haven't found the right solution.

here is my service:

import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import { map } from 'rxjs/operators';

@Injectable()
export class UserService {

  constructor(
    private _httpClient: HttpClient
  ) { }


  public auth(user) {
    return this._httpClient.post('users/login', user).pipe(map((resp: any) => resp.json()));
  }

}

and this is where I use the service:

import { Component, OnInit } from '@angular/core';
import { Router } from '@angular/router';
import { UserService } from '../../services/user.service';



@Component({
  selector: 'app-side-menu',
  templateUrl: './side-menu.component.html',
  styleUrls: ['./side-menu.component.scss']
})
export class SideMenuComponent implements OnInit {

  public positionsList: Array<any> = [];
  public selectedOption: string;
  public feedbackMessage: string;

  public email: string;
  public password: string;

  public formNotValid: boolean;

  constructor(
    private _userService: UserService,
    private _router: Router
  ) { 

  }

  ngOnInit() {
  }

  public sendLoginForm() {
    if(!this.email || !this.password){
      this.formNotValid = true;
      this.feedbackMessage = "Both fields are required to login!";
      return false;
    }

    const user = {
      email: this.email,
      password: this.password
    }

    this._userService.auth(user).subscribe(resp => {
      if(!resp.success){
        this.feedbackMessage = resp.message;
        return false;
      }
    });
  }

  public getSelectedOption(option) {
    this.selectedOption = "as " + option;
  }


}

Any idea will be appreciated.

Solution

You can just use the full URL in your call like this

this._httpClient.post(window.location.protocol + '//' + window.location.hostname + ':3000/' + 'users/login', user)

Ideally, you should have you microservices behind a reverse proxy and route your requests based on URI paths

Answered By - Pramodh Valavala