[RFC] cgit in git?

Background: I've been asked by the fedora project how to package cgit.
The problem is basically that cgit is designed to be statically linked
with a specific git release (i.e. libgit.a and xdiff/lib.a).

When manually building cgit from a tarball this isn't a problem:
'make get-git' will download the required git sources from kernel.org.
But the buildsystem/policy used by the fedora project does not allow
network access during package builds, and since it is quite unlikely
that the git package always will match the exact release needed by the
cgit package, I only see four options:
1) the fedora project makes a 'git-for-cgit' package containing the
needed release of the git sources
2) the cgit release tarballs includes the needed git sources
3) the cgit sources are subtree-merged into git
4) cgit is modified to link against libgit2

Option 1 seems unlikely to happen since such a 'git-for-cgit' package would basically require the fedora project to support two git packages.

Option 2 is doable but still requires the fedora project to support two git packages (but now the 'git-for-cgit' package is hidden inside the cgit source tree). The good thing about this option is that it only requires some minor modifications to the cgit releases.

Option 3 would solve the problem for the fedora project but is not for me to decide - it might become an extra maintenance burden on the git maintainer and community.

Option 4 is the correct solution but not a very practical one; it's currently hard to predict when libgit2 will be ready for general (c)git use.

Personally I'd love for option 3 to happen, hence this rfc.

On Thu, Dec 11, 2008 at 10:48:45PM +0100, Lars Hjemli <hjemli@gmail.com> wrote:

I don't say 2) is the ideal solution (probably 4) will be), but that's what we choosed for Frugalware and I think Fedora could live with it as well.

"Lars Hjemli" <hjemli@gmail.com> writes:

2b) make cgit .spec use _two_ tarballs as a source, one with cgit sources, one with git sources. This assumes that you always use released git version as a base.

This is immediate solution.

I wonder how likely this would be.

Option 4) would be probably best in long term, but libgit2 doesn't exists yet.

"Lars Hjemli" <hjemli@gmail.com> writes:

I do not understand why this is any extra work for fedora. Instead of running "make get-git" and then running your build procedure, they need to just run your build procedure because you now ship your source with the matching version of the git source, which sounds like the right thing to me. You do not install anything from the contained git.git area (we do not do shared objects, nor public header files) to the end product, right?

Doesn't cgit bind git.git as a subproject at the source level? I would expect that the most natural release tarball for such a project would be a single tarball that has both the superproject itself _and_ the submodules it contains already extracted, iow, the state of your tree after you run "make get-git".

On Thu, Dec 11, 2008 at 23:35, Junio C Hamano <gitster@pobox.com> wrote:

I imagined that it could have a ripple-effect on package dependencies, i.e. the git release used by cgit could have subtle 'incompatibilities' with the real git package, but I really don't know the first thing about packaging so this is just a guess.

Right.

Your expectation makes sense to me, thanks for elaborating.

Seth: would such a self-contained tarball solve the problems on your end?

-- larsh

Lars Hjemli wrote:

(I'm not Seth, nor do I play him on TV -- though I have been offered his role in a small town production of "How the Grinch Stole Christmas"... ;)

The downside to this is that cgit would be duplicating the git sources, and thus, so would any distribution packages. If there is a bug in git, both the git and cgit packages would need to be updated to fix it.

Basically, Fedora tries hard to use system libraries rather than having applications include their own local copies. (I recall some zlib vulnerabilities years back that required way too many packages to be rebuilt, since they each included their own copy of zlib.)

Obviously, since git is not intended to be used as a library, this doesn't exactly match that situation. But cgit is using git as a library at the moment and if we could find a way to only have one copy of the git sources to maintain, that'd be ideal from a distribution / packaging perspective. I do understand that it might not be as ideal from either git or cgit developer / maintainer perspective, so the consideration you're giving the issue is very much appreciated.

On Thursday 11 December 2008, Lars Hjemli wrote:

Option 5: Include cgit as a submodule in git.git. Then it's available to those who want it, but not cloned/built by default.

If that doesn't pan out, I also support option #3.

I've been a happy cgit user for a number of months, and have yet to find a single issue where cgit is not better than or equal to gitweb. I have nothing bad to say about gitweb per se, but cgit simply offers me a better user experience, not least because of its blazing speed.

Have fun!

...Johan