Tracking derivatives delta: explanations, history [Was: Sponsoring a Tails hackfest?]

[intrigeri <intrigeri@debian.org>]

Hi,

Paul Wise wrote (02 Jun 2014 15:56:56 GMT) :
> On Mon, Jun 2, 2014 at 9:03 PM, intrigeri wrote:
>> It seems to me that having more information about the content of
>> this delta, and perhaps more importantly the reasons behind it,
>> would be needed to make it useful.
>>
>> I'll look into the DEX and the derivatives census scripts for ideas,
>> focusing on "what kind of question on this topic do we need to easily
>> find the answer to?" first. Input is welcome, of course :)

> The replacement for stabile.d.o (snapshot.d.o secondary replica) is
> getting closer to being ready, [...]. Here are the results from
> before the stabile.d.o hardware failure though: [...]

We have looked into this today at the Tails summit. [Disclaimer:
sorry if we've missed existing data or tools.] We have identified two
possible goals that are not achieved by the existing tools' output:

a. Enable anyone to easily find potential action items; that is:
   make it easy to filter what should be ignored ("legit" delta) and
   what should be improved.

b. Visualize the evolution of a given derivative's delta with Debian
   => detect if the situation is improving or getting out of control
   => derivatives developers can be happy and proud, or react
   promptly; Debian contributors can evaluate how a given derivative
   is "nice" to Debian.

We have also thought *a bit* of potential technical changes that would
help us reach these goals:

1. Have explanations about the delta in each case

   Ideally, for 3.0 (quilt) packages, compare-source-package-list
   could look into debian/patches for derivatives-specific patches,
   and retrieve information from DEP-3 headers.

   For other kinds of packages, it seems that the metadata would need
   to be added to some fine in the debian/ directory, possibly using
   the DEP-3 format. This also would be useful to document the delta
   of 3.0 (quilt) packages that is not expressed in debian/patches,
   e.g. shipping a newer upstream version than Debian.

2. Generate graphs displaying the evolution of a derivative's delta

   This requires storing history of at least sources.{new,patches},
   and having some code that generates graphs out of it. Presumably,
   once specified properly, this could be a great task for someone
   learning programming.

Thoughts, opinions?
Volunteers to do give a hand?

Cheers,
-- 
intrigeri