Bug#845965: python-apt: Please support TagFile(filename, real_path=path) - or similar

[Niels Thykier <niels@thykier.net>]

Package: python-apt
Version: 1.1.0~beta5
Severity: wishlist

Hi,

In Britney, we are considering to add support for "by-hash" mirrors.
In the current design of the "by-hash", the by-hash'ed files do not
have the extenstion, so we would have to re-implement the
decompression support from APT (which I would rather not, since APT
handles this rather well for us at the moment).

I see multiple ways to do this.  The simpliest for me would be if the
TagFile object supported two file names.  The one to use for detecting
the compression and a separate one, which is the actual path to open.

Alternatives:

 * Pass the expected extention / compression algorithm as a separate
   parameter.

 * An object that reads an (In)Release file and that can be asked to open a
   TagFile for a given file listed in the (In)Release file (e.g.
   "main/binaries-amd64")

I would love to see something like this in stretch, so we can add
support for it in Britney soon. :) I am happy to assist with the parts
I am able.

Thanks,
~Niels