Re: gitweb / cg-export

[Fredrik Kuivinen <freku045@student.liu.se>]

On Wed, Aug 16, 2006 at 05:02:36PM +0530, Aneesh Kumar K.V wrote:
> Aneesh Kumar K.V wrote:
> >Jakub Narebski wrote:
> >>Toby White wrote:
> >>
> >>>I was wondering if a feature like the following would be of
> >>>use to anyone except me: I'd like to be able to download
> >>>the full source of a given tree from gitweb.
> >>[...]
> >>So you want to have snapshot of a tree. Why not snapshot of a commit, 
> >>or of a tag?
> >>
> >>>I've quickly hacked gitweb to do this for me - patch below.
> >>>
> >>>It adds an extra link to the 'commit' page. Next to the link
> >>>that would lead you to 'tree', there is 'tar.gz' which simply
> >>>returns the tar.gz of the same tree.
> >>>
> >>>The patch is against the version of gitweb currently in
> >>>Debian, which is, erm, '264-1', apparently, because that's
> >>>what I had to hand.
> >>
> >>It is really better to hack git with git. And you can use current gitweb
> >>with old git (well, not always, as current gitweb requires --full-history
> >>option to git-rev-list to be available).
> >>
> >
> >How about the below on top of latest git
> 
> Add it to git_commit too. The patch contains the pervious changes also.
> 

Nice.

> +sub git_snapshot {
> +	if (!defined $hash) {
> +		$hash = git_get_head_hash($project);
> +	}
> +	print $cgi->header(-type=>'application/x-tar',
> +			  -Content-Encoding=>'x-gzip', -status=> '200 OK');
> +	open my $fd, "-|", "$GIT tar-tree $hash $project | gzip -c9" or die_error(undef, "Execute git-tar-tree failed.");

It might be better to use -6 (the default compression/speed trade-off)
instead of using -9 (best but slowest compression) here.  Or maybe
even make it configurable. On some servers it is probably preferable
to make the snapshot (slightly) larger and gain some cpu time.

To get some numbers I made a small benchmark with the current git
tree. I get the following on my machine:

Compression/speed    Size   Time
-1                   1.1M   0.16s
-6                   923K   0.36s
-9                   917K   0.50s  

- Fredrik