Re: Bug#942893: ftp.debian.org: please drop MD5sum lines from Packages

[Ansgar <ansgar@43-1.org>]

Daniel Kahn Gillmor writes:
> The Packages file is growing, and we would like to keep it smaller.
>
> The MD5sum lines are vestigial at this point.  Anything that they do
> can be done better with the data from the SHA256sum lines.

I agree it would be nice to remove MD5sum from Packages; there are a few
other fields that might also not be that useful (e.g. Maintainer).

> #887831 suggests that jigdo may currently still be broken if MD5sum
> goes away, but perhaps that's more of a reflection on the unmaintained
> state of jigdo than it is on the state of the archive.

>From looking, I believe it is debian-cd's tools/grab_md5 that is using
the MD5sum from Packages (and Sources) to avoid having to compute all
these checksums itself.

We could look into either

 - writing MD5sum in a separate file only used by debian-cd (if present,
   otherwise debian-cd should fall back to using Packages), or

 - using a (truncated) sha256sum; this requires that the jigdo client
   only uses the "md5sum" as an opaque identifier for a file.

I've CC'ed debian-cd@ for input.

Ansgar