Package registry: downloading files from UI doesn't respect filenames

🔥 Problem

When browsing the Package Registry UI, we can get the details of a package with the related files. Clicking on a file will download it.

Historically, the browser would open a download file prompt and the package filename would be used as the default value for the name for the file.

It seems that this doesn't work anymore. Example: https://gitlab.com/issue-reproduce/packages/maven/maven-package/-/packages/14601208, clicking on any file will use download as a filename.

What is strange is that locally, the backend properly use the package filename.

To be complete here, this part has been updated recently with Resolve "Packaging: Support directory structure" (!141361 - merged) where support for directly like filenames (such as foo/bar/file.txt) has been added. This is mainly for the Generic package registry but the changes impacted the UI part too which is used by any supported package format.

🚨 Workaround

• No known workaround to download the package file with the correct name at this point.
• The downloaded file itself is fine. User can rename the file with the correct extension manually.

🚒 Solution

• There has to be something with the #send_upload function here.
  • This could be a configuration that is different between gitlab.com and the local instance.
• Investigate and find a solution to guarantee that the filename sent is the one from the package file.

Ref

Internal only ZD ticket ref: 530713, 530797, 530855, 530885, 530992