Function readBlob

src/common/util.js:405–413

(blob, asBuffer)

 * @return {Promise<string|ArrayBuffer>}
 */
export function readBlob(blob, asBuffer) {
  return new Promise((resolve, reject) => {
    const reader = new FileReader();
    reader.onload = () => resolve(reader.result);
    reader.onerror = reject;
    if (asBuffer) reader.readAsArrayBuffer(blob);
    else reader.readAsDataURL(blob);
  });
}