Add Download file action to file meatballs button

[bergice]

No description provided.

[maxime-rainville]

I second everything @kinglozzer has said.

The "insert a link on the page and click on it" method feels kind of weird, but can't find a better way to trigger a download in JS.

Have you given some thoughts about trying to make the Download action an actual link? This would seem like the ideal approach. Would probably require more work, but it could be reuse in other places.

It would be nice to have some test coverage of this, but I'm not sure there's a nice elegant way of asserting that "my browser asked me to download this file". Seems like there's some way to do it in Behat but I haven't tried it.

[bergice]

Have you given some thoughts about trying to make the Download action an actual link? This would seem like the ideal approach. Would probably require more work, but it could be reuse in other places.

It can be done with a LiteralField. See: vendor/silverstripe/asset-admin/code/Forms/FileFormFactory.php:103 - but it would require some CSS changes as well.

[maxime-rainville]

Using a LiteralField might be a quick way to hack it in, but the correct way to do it probably involves updating something the FormBuilder in admin and updating it so that if a specific attribute on the FormAction gets specified, it renders it as a link instead of an actual button. If you feel like trying it out, we could have a look ... but it's very much a nice to have.

[maxime-rainville]

Almost done. I still have a bit of an issue with the focus, but all my other concern have been addressed.

[maxime-rainville]

I tested in Chrome, Firefox and IE11. It all works fine. Note that in IE11, it wants to display the images rather than download them. You might be able to force IE to download the files by adding a download attribute to the link, but I'm not sure.

[bergice]

I tested in Chrome, Firefox and IE11. It all works fine. Note that in IE11, it wants to display the images rather than download them. You might be able to force IE to download the files by adding a download attribute to the link, but I'm not sure.

I think this relies on browser settings and response headers in order to work.

[kinglozzer]

Note that in IE11, it wants to display the images rather than download them. You might be able to force IE to download the files by adding a download attribute to the link, but I'm not sure.

Apparently IE doesn’t support the download attribute: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/a#Browser_compatibility. We’d have to set up a new endpoint that adds the Content-Disposition header, so I think we should just leave it as a legacy browser quirk

[maxime-rainville]

Everything works like a charm now. I've rebased this guy and sqashed all the commits.

Merge on green