Bug#278289: ITP: apt-dupdate -- diff-based update of APT's index files

[Eduard Bloch <blade@debian.org>]

Package: wnpp
Severity: wishlist

* Package name    : apt-dupdate
  Version         : 0.0.1
  Upstream Author : me
* License         : BSD
  Description     : diff-based update of APT's index files

apt-dupdate is beeing written right now. The server part is almost done,
the client should be not a big deal. apt-dupdate is similar to the
unofficial apt-pupdate package and uses the same base idea: the
Packages/Sources files are updated using diff/patch files to the
previous version which is already downloaded. The advantage is
impressing: daily diffs for Sid are about 35KiB in size (average,
bzip2ed) compared to >=3MiB downloaded by APT (for main, gziped).

The advantages of apt-dupdate compared to apt-pupdate:

 - it will actually work. bjb seems to be MIA since the big server
   compromise, the diff update scripts on people.d.o are apparently not
   restored
 - in difference to apt-pupdate, I do not use chains of small diffs,
   based on days and managed by the server. Instead, the server provides
   the patch for a md5sum which contains the diffs between the version
   of the client and the current one (when the server has data for the
   old version, of course)
 - it will be faster on high-latency links. apt-pupdate AFAICS needed
   n*2+2 http requests where n=#days. apt-dupdate will use exactly one
   request.
 - it will be faster on low-speed links since one chunk of data
   compresses much better than n small chunks. apt-dupdate will use
   bzip2 instead of gzip.

-- System Information:
Debian Release: 3.1
  APT prefers unstable
  APT policy: (500, 'unstable'), (500, 'testing'), (1, 'experimental')
Architecture: i386 (i686)
Kernel: Linux 2.6.9
Locale: LANG=de_DE.UTF-8, LC_CTYPE=de_DE.UTF-8