Download response.data as a file, through Blob()

file-download-from-fetch.js

// Reference: https://gist.github.com/davalapar/d0a5ba7cce4bc599f54800da22926da2

export function downloadFile(data, filename, mime) {
  // It is necessary to create a new blob object with mime-type explicitly set
  // otherwise only Chrome works like it should
  const blob = new Blob([data], {type: mime || 'application/octet-stream'});
  if (typeof window.navigator.msSaveBlob !== 'undefined') {
    // IE doesn't allow using a blob object directly as link href.
    // Workaround for "HTML7007: One or more blob URLs were
    // revoked by closing the blob for which they were created.
    // These URLs will no longer resolve as the data backing
    // the URL has been freed."
    window.navigator.msSaveBlob(blob, filename);
    return;
  }
  // Other browsers
  // Create a link pointing to the ObjectURL containing the blob
  const blobURL = window.URL.createObjectURL(blob);
  const tempLink = document.createElement('a');
  tempLink.style.display = 'none';
  tempLink.href = blobURL;
  tempLink.setAttribute('download', filename);
  // Safari thinks _blank anchor are pop ups. We only want to set _blank
  // target if the browser does not support the HTML5 download attribute.
  // This allows you to download files in desktop safari if pop up blocking
  // is enabled.
  if (typeof tempLink.download === 'undefined') {
    tempLink.setAttribute('target', '_blank');
  }
  document.body.appendChild(tempLink);
  tempLink.click();
  document.body.removeChild(tempLink);
  setTimeout(() => {
    // For Firefox it is necessary to delay revoking the ObjectURL
    window.URL.revokeObjectURL(blobURL);
  }, 100);
}