comps discussion at fudcon and the future

[Josh Boyer]

On Wed, Jan 14, 2009 at 02:51:52PM -0500, seth vidal wrote:
>
>On saturday at fudcon we had a small talk (meaning there were only 4 of
>us there: Jeroen, Jeremy, James, and Me) about the future of comps and
>what we need.
>
>We came up with a fairly radical departure that will take some work to
>implement and probably won't land for F11 but it is worth discussing a
>bit now. Please read through the whole thing before jumping all over it.
>
>
>Problems we see:
>- browsing packages is a difficult problem when you have 10000+ pkgs.
>- comps has a lot of meanings and it is not obvious what they all are/do
>- conditional pkgs (which provide a way of saying "install pkgX only 
>  if pkgY is installed) are several colors of doom b/c they aren't a 
>  dependency relationship and creates clutter on systems.
>- users expect groups to be more persistent on their systems and to act
>  more like pkgs (ie: yum update should update groups, too)
>- optional/default/mandatory pkgs are confusing and not useful to most
>  people - the types are only useful when browsing, not when installing.
>
>
>We're still going to have a comps/groups file in the metadata but we'll
>be removing package types. If a package is a member of a group then
>that's it. It's in the group.
>
>When someone goes to install the group: 'yum groupinstall
>mygroup-of-fun' or 'yum install @mygroup-of-fun' then yum will grab the
>comps/groups file from each repo, look if the group you're requesting is
>there. If so it will create a metapkg rpm (a package containing only
>requirements) on the packages that exist in the repositories that are
>listed in that group. Then it will depsolve and install that pkg. The
>package name will be @mygroup-of-fun. The package version will be a hash
>of the contents of the package along with a timestamp. It needs to be
>timestamp-based so the version is increasing so we can 'update' these
>pkgs.
>
>We'll make sure that yum knows about @pkgs to be looked up against the
>comps file (which should be  significantly smaller now).

Bear with this question, but...

I often find myself doing "yum install <some group>" and messing around
with that a bit.  Then I typically find that I only really want 1/2 the
group or something.

With the metapkg installed, won't I have to yum remove that in order to
remove any individual packages from in that group?  If so, will yum go
into a depsolving erasure spree and try to remove the whole group
instead of just the package or two I listed?

josh