How do I set the baseUrl for Angular HttpClient?

Question

I did not find a way in the documentation to set the base API URL for HTTP requests. Is it possible to do this with the Angular HttpClient?

Answer 1

Excerpts from Visual studio 2017 asp.net core webapi angular sample application.

include below lines in Main.ts

export function getBaseUrl() {
  return document.getElementsByTagName('base')[0].href;
}

const providers = [
  { provide: 'BASE_URL', useFactory: getBaseUrl, deps: [] }
];

in your component

  constructor(http: HttpClient, @Inject('BASE_URL') baseUrl: string) {
    http.get(baseUrl + 'api/SampleData/WeatherForecasts').subscribe(result => {
      this.forecasts = result;
    }, error => console.error(error));
  }

my complete main.ts code looks like below

import { enableProdMode } from '@angular/core';
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';

import { AppModule } from './app/app.module';
import { environment } from './environments/environment';

export function getBaseUrl() {
  return document.getElementsByTagName('base')[0].href;
}

const providers = [
  { provide: 'BASE_URL', useFactory: getBaseUrl, deps: [] }
];

if (environment.production) {
  enableProdMode();
}

platformBrowserDynamic()
  .bootstrapModule(AppModule)
  .catch(err => console.error(err));

my component code looks like below

import { Component, Inject } from '@angular/core';
import { HttpClient } from '@angular/common/http';

@Component({
  selector: 'fetch-weather',
  templateUrl: './weather.component.html',
  styleUrls: ['./weather.component.scss']
})

export class WeatherComponent {
  public forecasts: WeatherForecast[];

  constructor(http: HttpClient, @Inject('BASE_URL') baseUrl: string) {
    http.get(baseUrl + 'api/SampleData/WeatherForecasts').subscribe(result => {
      this.forecasts = result;
    }, error => console.error(error));
  }
}

interface WeatherForecast {
  dateFormatted: string;
  temperatureC: number;
  temperatureF: number;
  summary: string;
}