import { NgModule } from '@angular/core';
import { Routes, RouterModule, Router } from '@angular/router';

import { LoginComponent } from './login/login.component';
import { ProfileComponent } from './profile/profile.component';

const routes: Routes = [
  { path: '', redirectTo: '/login', pathMatch: 'full'},
  { path: 'login', component: LoginComponent },
  { path: 'profile', component: ProfileComponent }
]

@NgModule({
  imports: [ RouterModule.forRoot(routes) ],
  exports: [ RouterModule ]
})
export class AppRoutingModule { }

import { Injectable } from '@angular/core';
import { HttpInterceptor } from '@angular/common/http'

@Injectable({
  providedIn: 'root'
})
export class TokenInterceptorService implements HttpInterceptor {

  constructor() { }

  intercept(req, next) {
    
    if (this.getToken()) {
      let tokenizedReq = req.clone({
        setHeaders : {
          Authorization : "Bearer "
        }
      })
  
      return next.handle(tokenizedReq);
    } else {
      return next.handle(req);
    }

  }

  private getToken() {
    if (!!localStorage.getItem("token")) {
      return localStorage.getItem("token")
    } else {
      return false;
    }
  }
}

...
import { HttpClientModule, HTTP_INTERCEPTORS } from '@angular/common/http';
import { TokenInterceptorService } from './token-interceptor.service';
...

@NgModule({
  ...
  providers: [
    ...,
    TokenInterceptorService, 
    {
      provide: HTTP_INTERCEPTORS,
      useClass: TokenInterceptorService,
      multi: true
    }
  ]
})
export class AppRoutingModule { }

import { Injectable } from '@angular/core';
import { HttpClient, HttpHeaders } from '@angular/common/http'
import { Observable } from 'rxjs';
@Injectable({
  providedIn: 'root'
})
export class ConnectorService {

  constructor(
    private http: HttpClient
  ) { }

  public getRequest(params) {
    let res = this.http.get(
      "http://dp.localhost.com/index.php",
      {
        params : params
      }
    ).subscribe(res => {
      //  Update the token in localstorage if available
      this.updateToken(res);
      // Return the response to the invoking method
      return res;
    });
  }

  public postRequest(params) {

  }

  public updateToken(response) {
    if (response["token"] !== undefined) {
      localStorage.setItem("token", response["token"]);
    }
  }

}