PRO-2191 download

[abea]

No description provided.

[linear]

PRO-2191 As an editor, once my export file has been generated it will automatically start downloading for me

This is a front-end task for presenting the generated file to the user to be downloaded.

A separate ticket exists for the actual handling of the export process.

Acceptance criteria:

• After I've clicked the export button, and the file has been generated, I will automatically be prompted by the browser to download it

See below for a design with the relevant notifications, once the "Export complete" notification is sent, the browser should prompt the user to download the file automatically.

[boutell]

We might need content-disposition here, let me know if I'm wrong. Maybe we don't simply because none of the output formats are native to the browser anyway, but it's a good idea to specify downloading is the intent.

[boutell]

Do you really get a download this way across browsers with just _blank? I would think you would need to use a route that sends with with Content-Disposition: Attachment (I think I sent you the 2.x route we use for it).

[abea]

The only one I see that does not download is Safari, which opens the CSV as text in a new tab. This is essentially the way we handled it in the A2 version. https://github.com/apostrophecms/apostrophe-pieces-export/blob/main/public/js/export-modal.js#L39

[abea]

Since we're saving the file to the public directory I'm not sure how much we get out of putting it behind another route.

[boutell]

In the A2 version we used a route to download it and that route emits the right Content-Disposition header, as a result of which I betcha Safari doesn't show it in a tab.

[boutell]

(In A3 this would need to be in routes because we need to respond directly via res and in A3 apiRoutes just return a body.)

  // Provides a simple route to download a file as an attachment, rather than
  // viewing it. Pipes it from the regular public URL to avoid acting as a
  // bypass of permissions
  self.apiRoute('get', 'download', async (req, res) => {
    const _id = self.apos.launder.id(req.query._id);
    const info = await self.db.findOne({
      _id: _id
    });
    if (!info) {
      return res.status(404).send('notfound');
    }
    const url = self.url(info, { size: 'original' });
    res.setHeader('Content-Disposition', `attachment; filename="${path.basename(url)}"`);
    res.setHeader('Content-Type', 'application/octet-stream');
    const resolvedUrl = (new URL(url, req.absoluteUrl)).toString();
    await request(resolvedUrl).pipe(res);
  });

[boutell]

In A2 that route is in core, as there can be other applications for reliably downloading rather than viewing an attachment, which I think is still the case.

[abea]

This is essentially the way we handled it in the A2 version.

By that I meant it's how it was done in the pieces export module.