Re: [PATCH] gitweb: snapshot cleanups & support for offering multiple formats

[Luben Tuikov <ltuikov@yahoo.com>]

--- Junio C Hamano <gitster@pobox.com> wrote:
> Jakub Narebski <jnareb@gmail.com> writes:
> 
> > On Tue, 17 July 2007, Matt McCutchen napisał:
> > ...
> >> Alert for gitweb site administrators: This patch changes the format of
> >> $feature{'snapshot'}{'default'} in gitweb_config.perl from a list of
> >> three pieces of information about a single format to a list of one or
> >> more formats you wish to offer from the set ('tgz', 'tbz2', 'zip').
> >> Update your gitweb_config.perl appropriately.  The preferred names for
> >> gitweb.snapshot in repository configuration have also changed from
> >> 'gzip' and 'bzip2' to 'tgz' and 'tbz2', but the old names are still
> >> recognized for compatibility.
> >
> > This alert/warning should probably be put in RelNotes for when it would
> > be in git.git
> 
> Does anybody else worry about the backward imcompatibility, I
> wonder...  List?

I wouldn't mind an improvement in the snapshot area of gitweb.
I wasn't really happy with the snapshot feature as it was originally
implemented, as it would generate a tar file with ".tar.bz2"
name extension, but the file was NOT bz2, and I had to always
manually rename, bz2, and rename back.

> I really hate to having to say something like that in the
> RelNotes.  I do not think this is a good enough reason to break
> existing configurations; I would not want to be defending that
> change.
> 
> >> I thought of another incompatibility: previously bookmarked snapshot
> >> URLs will no longer work because they lack the new "sf" parameter.  I
> >> don't care about this; do any of you?
> >
> > I think either having good error message, or using first format avaiable
> > would be good enough.
> 
> I doubt bookmarked snapshot URL would make sense to begin with,
> so this would be Ok.
> 
> I am wondering if something like this patch (totally untested,
> mind you) to convert the old style %feature in configuration at
> the site at runtime would be sufficient.

"totally untested" is a problem.  Anything going into gitweb for
public consumption (master branch, next ok), should be completely
and exhaustively tested.

   Luben

> 
> diff --git a/gitweb/gitweb.perl b/gitweb/gitweb.perl
> index f17c983..cdec4d0 100755
> --- a/gitweb/gitweb.perl
> +++ b/gitweb/gitweb.perl
> @@ -236,9 +236,39 @@ our %feature = (
>  		'default' => [0]},
>  );
>  
> +# Functions to convert values from older gitweb configuration
> +# into the current data format
> +sub gitweb_bc_feature_snapshot {
> +	my $def = $feature{'snapshot'}{'default'};
> +	# Older definition was to have either undef (to disable), or
> +	# a three-element array whose first element was content encoding
> +	# without leading "application/".
> +	return if (ref $def ne 'ARRAY');
> +	if (!defined $def->[0] && @$def == 1) {
> +		# Disabled -- the new way to spell it is to have an empty
> +		# arrayref.
> +		$feature{'snapshot'}{'default'} = [];
> +		return;
> +	}
> +	return if (@$def != 3);
> +	for ($def->[0]) {
> +		if (/x-gzip/) {
> +			$feature{'snapshot'}{'default'} = ['tgz'];
> +		}
> +		if (/x-bz2/) {
> +			$feature{'snapshot'}{'default'} = ['tbz2'];
> +		}
> +		if (/x-zip/) {
> +			$feature{'snapshot'}{'default'} = ['zip'];
> +		}
> +	}
> +}
> +
>  sub gitweb_check_feature {
>  	my ($name) = @_;
>  	return unless exists $feature{$name};
> +	eval "gitweb_bc_feature_$name()";
> +
>  	my ($sub, $override, @defaults) = (
>  		$feature{$name}{'sub'},
>  		$feature{$name}{'override'},
> 
>