Problem with HttpInterceptor in Angular 8 - HTTPInterceptor is not triggered - angular8

Question

I have a simple code of HttpInterceptor, i'm trying to add some data in the request headr, but this is not working.
MyInterceptorService Class Code :
import { Injectable } from '#angular/core';
import { HttpRequest, HttpHandler, HttpEvent, HttpInterceptor } from '#angular/common/http';
import { Observable } from 'rxjs';
#Injectable()
export class MyInterceptorService implements HttpInterceptor {
constructor() { }
intercept(req:HttpRequest<any>, next:HttpHandler):Observable<HttpEvent<any>>
{
console.log("hello");
return next.handle(
req.clone({
headers: req.headers.set('Authorization', 'Bearer ')
})
);
}
}
Module Class Code
import { BrowserModule } from '#angular/platform-browser';
import { NgModule } from '#angular/core';
import { AppRoutingModule } from './app-routing.module';
import { AppComponent } from './app.component';
import {FormsModule} from '#angular/forms';
import { SecretComponent } from './secret/secret.component';
import { ErreurComponent } from './erreur/erreur.component';
import { HTTP_INTERCEPTORS } from '#angular/common/http';
import { MyInterceptorService } from './my-interceptor.service';
#NgModule({
declarations: [
AppComponent,
SecretComponent,
ErreurComponent,
],
imports: [
BrowserModule,
AppRoutingModule,
FormsModule
],
providers: [
{
provide: HTTP_INTERCEPTORS,
useClass: MyInterceptorService,
multi: true
}
],
bootstrap: [AppComponent]
})
export class AppModule { }
The Console message is never displayed and the Http Header is not updated

Answer 1

Are you sure you make an HTTP-request somewhere in your code? For example:
import { Component, OnInit } from '#angular/core';
import { HttpClient, HttpHeaders } from '#angular/common/http';
#Component({
selector: 'my-app',
templateUrl: './app.component.html',
styleUrls: [ './app.component.css' ]
})
export class AppComponent implements OnInit {
constructor(private http: HttpClient) {}
ngOnInit() {
this.http.get('http://www.google.com')
.subscribe();
}
}
I made a Stackblitz example with copy-paste of your MyInterceptorService and it displays the console 'hello' message: https://stackblitz.com/edit/angular-rhpnjg