repotag in EPEL

[Fernando Lopez-Lezcano]

On Tue, 2007-05-01 at 11:10 +0200, Thorsten Leemhuis wrote:
> Fernando Lopez-Lezcano schrieb:
> > [...]
> > AFAIK repotags have not caused technical
> > problems when used, they _have_ been useful, and they work now. 
> 
> repotags are part of the release and as such they influence the
> version-comparison when rpm determinates which rpm package is the
> newest. Some people call that a "technical problem".

How is having a repotag in the "Release:" tag semantically _different_
from having only a number and an optional disttag? 

> In other words: the repo with the "highest" repotag wins:
> 
> [thl at notebook ~]$ rpmdev-vercmp 0 1.1 5 0 1.1 5.at
> 0:1.1-5.at is newer
> [thl at notebook ~]$ rpmdev-vercmp 0 1.1 5.at 0 1.1 5.epel
> 0:1.1-5.epel is newer
> [thl at notebook ~]$ rpmdev-vercmp 0 1.1 5.epel 0 1.1 5.rf
> 0:1.1-5.rf is newer
> [thl at notebook ~]$ rpmdev-vercmp 0 1.1 5.rf 0 1.1 5.zzzzzzzzzz
> 0:1.1-5.zzzzzzzzzz is newer
> 
> > [...]

If I may state the obvious, any component of the "Release:" tag
influences the ordering. The numbers there do that, the distag there (if
present) does that and the repotag there does that as well. None of the
components have a magical meaning that makes it right[1]. 

Within a given repository the "extra" components (disttag, repotag) are
irrelevant as they are a constant. The arbitrary number(s) at the
beginning of the "Release:" tag will determine which package is newer,
and hopefully packagers and the build system will keep them sane and
nicely e-v-r ordered :-)

So, I dare say there are no technical problems within a repository that
could be caused by adding a repotag. 

Release tag comparison between repositories is meaningless. There is no
"right way" of comparing between repositories. Having only a number
there has the same _meaning_ in comparisons between repositories as
having a number, an optional disttag and a repotag. To restate it
differently, if an added repotag is a concern because of the fact that
it can define the ordering of packages between repositories, then the
already existing number there should raise exactly the same concern as
it has _exactly_ the same effect. _All_ of the components of the
"Release:" tag, when comparing between repositories, are meaningless. 

So, I dare say there are no technical problems in comparing packages
between repositories that could be caused by adding a repotag. 

[furthermore and in case it was missed, when I wrote "AFAIK repotags
have not caused technical problems when used, they _have_ been useful,
and they work now." it means what it says, there have NOT been problems
with them - there's nothing magical in EPEL that would suddenly cause
problems now, I think]

-- Fernando

[1] you can also add letters, numbers, dates, etc that spill from the
"Version:" tag to the "Release:" tag when packaging cvs, svn, beta or rc
releases.