By default the new Angular Http client (introduced in v4.3.1) uses JSON as the data format for communicating with the backend API. However, there might be situations where you may want to use some other format, like text/plain for fetching a CSV file. Using the responseType property this can be achieved quite easily.

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

@Injectable()
export class PeopleService {

  constructor(private http: HttpClient) {}

  fetchPeople(): Observable<Object> {
    return this.http
      .get('data/people.txt', { responseType: 'text'});
  }

}