rfc: give koji diff capabilities

[David Timms]

On 21/06/10 09:38, Thomas Spura wrote:
>> Any comments (other than 'show me the money/code') ?
>
> I don't see a benefit of that... When a build fails, it kills all
> other current builds of other architectures, so you need to check that
> architecture, that fails first and the diff would not contain the error.
Hi Thomas, good point. But reality might be different:
http://koji.fedoraproject.org/koji/taskinfo?taskID=2260035 -> build.log

The x86_64 build failed, and is says that the i686 was cancelled.

However, the build.log shows that the package and -debuginfo .rpms were 
created, ie the build actually succeeded. This seems like a bug in the 
koji web interface.

Having the non-failing build be cancelled may not be optimal; I have 
definitely found it helpful to compare the build logs of different 
archs, when one succeeds (or at least gets further). It helps to see the 
diff in log results to understand what is different about the process 
between each build.

> Other that that. The diff would show, different which different
> packages are installed, e.g. gcc.i386 instead of gcc.x86_64, which
> doesn't interest me either...
> (And different requires etc.)
That would be more bonus points for the diff to optionally ignore !
A decent visual diff will highlight lines that are different, but also 
show the actual characters that differ (I don't know if viewvc can do that).

> What would be the benefit of such a feature?
Resolving build problems more quickly:
- what changed in the build process from arch to arch ...
- what changed in the bp from fedora release to fedora release ...
- what changed in the bp compare to an earlier version-release ...

However, for the less experienced package maintainers: tell me shortest 
time for you to determine the cause for the failure in:
http://koji.fedoraproject.org/koji/taskinfo?taskID=2260034  -> build.log

Now, would these screen shots from a visual diff program have reduced 
the time for working out both the error, and the cause ?
http://members.iinet.net.au/~timmsy/rakarrack/meld.rakarrack.diff1.png
http://members.iinet.net.au/~timmsy/rakarrack/meld.rakarrack.diff2.png