How to request for a non-json octet-stream in angular 6 using HttpClient?

Question

I am working on an Angular 6 project. One of the web service return the octet-stream of a file. I have to create a Blob of the file and download it. I am not getting the response inside subscribe. How can I request for non-json octet-stream response?

downloadFile(filePath: string): Observable<HttpResponse<Any>> {
    this.http.post<any>(this.getFileDownloadPath(), { stringParam: filePath }, { observe: 'response' }).subscribe(
        (resp) => {
            this.triggerDownloadFile(resp.body);
        },
        (err) => {
            console.log('err');
        }
    );
}

triggerDownloadFile(data: Response) {
    const blob = new Blob([data], { type: 'application/octet-stream' });
    const url = window.URL.createObjectURL(blob);
    window.URL.revokeObjectURL(url);
    window.open(url);
}

Answer 1

import { Component, OnInit } from '@angular/core';
import { DomSanitizer } from '@angular/platform-browser';

@Component({
  selector: 'my-app',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent implements OnInit {
  name = 'Angular 5';
  fileUrl;
  constructor(private sanitizer: DomSanitizer) {  }
  ngOnInit() {
    const data = 'some text';
    const blob = new Blob([data], { type: 'application/octet-stream' });

    this.fileUrl = this.sanitizer.bypassSecurityTrustResourceUrl(window.URL.createObjectURL(blob));
  }

}

<a [href]="fileUrl" download="file.txt">DownloadFile</a>