[PaulHoule]

It's completely possible to download the metadata for a wheel without downloading the whole wheel.

Specifically a wheel is really a ZIP file, which has a superblock at the end that tells you how long the directory is, a directory just before the superblock. It is one or two range requests to get the location of the .dist-info/METADATA file and just one to read it.

Trouble is that this doesn't work for egg files, which are still around. In the example of a company that had Python systems that exceeded what pip could handle, we made our own private repository of wheels from eggs.