import { Observable } from 'rxjs';

export function blobToBase64(blob: Blob): Observable<string> {
  return new Observable(observer => {
    const fileReader = new FileReader();
    fileReader.onload = () => {
      observer.next(fileReader.result as string);
      observer.complete();
    };
    fileReader.onerror = err => observer.error(err);
    fileReader.readAsDataURL(blob);

    return () => {
      fileReader.onload = null;
      fileReader.onerror = null;
      fileReader.abort();
    };
  });
}