gitweb: Support for tag clouds

diff --git a/gitweb/gitweb.perl b/gitweb/gitweb.perl
index 83f810ad46cd2dfcea37308791ba64870ebfbd3c..0cb29705b2e8b343b162554ceef094741400fe56 100755 (executable)
--- a/gitweb/gitweb.perl
+++ b/gitweb/gitweb.perl
@@ -282,6 +282,24 @@ BEGIN
        'forks' => {
                'override' => 0,
                'default' => [0]},
+
+       # Allow gitweb scan project content tags described in ctags/
+       # of project repository, and display the popular Web 2.0-ish
+       # "tag cloud" near the project list. Note that this is something
+       # COMPLETELY different from the normal Git tags.
+
+       # gitweb by itself can show existing tags, but it does not handle
+       # tagging itself; you need an external application for that.
+       # For an example script, check Girocco's cgi/tagproj.cgi.
+       # You may want to install the HTML::TagCloud Perl module to get
+       # a pretty tag cloud instead of just a list of tags.
+
+       # To enable system wide have in $GITWEB_CONFIG
+       # $feature{'ctags'}{'default'} = ['path_to_tag_script'];
+       # Project specific override is not supported.
+       'ctags' => {
+               'override' => 0,
+               'default' => [0]},
 );
 
 sub gitweb_check_feature {
@@ -1762,6 +1780,67 @@ sub git_get_project_description {
        return $descr;
 }
 
+sub git_get_project_ctags {
+       my $path = shift;
+       my $ctags = {};
+
+       $git_dir = "$projectroot/$path";
+       foreach (<$git_dir/ctags/*>) {
+               open CT, $_ or next;
+               my $val = <CT>;
+               chomp $val;
+               close CT;
+               my $ctag = $_; $ctag =~ s#.*/##;
+               $ctags->{$ctag} = $val;
+       }
+       $ctags;
+}
+
+sub git_populate_project_tagcloud {
+       my $ctags = shift;
+
+       # First, merge different-cased tags; tags vote on casing
+       my %ctags_lc;
+       foreach (keys %$ctags) {
+               $ctags_lc{lc $_}->{count} += $ctags->{$_};
+               if (not $ctags_lc{lc $_}->{topcount}
+                   or $ctags_lc{lc $_}->{topcount} < $ctags->{$_}) {
+                       $ctags_lc{lc $_}->{topcount} = $ctags->{$_};
+                       $ctags_lc{lc $_}->{topname} = $_;
+               }
+       }
+
+       my $cloud;
+       if (eval { require HTML::TagCloud; 1; }) {
+               $cloud = HTML::TagCloud->new;
+               foreach (sort keys %ctags_lc) {
+                       # Pad the title with spaces so that the cloud looks
+                       # less crammed.
+                       my $title = $ctags_lc{$_}->{topname};
+                       $title =~ s/ /&nbsp;/g;
+                       $title =~ s/^/&nbsp;/g;
+                       $title =~ s/$/&nbsp;/g;
+                       $cloud->add($title, $home_link."?by_tag=".$_, $ctags_lc{$_}->{count});
+               }
+       } else {
+               $cloud = \%ctags_lc;
+       }
+       $cloud;
+}
+
+sub git_show_project_tagcloud {
+       my ($cloud, $count) = @_;
+       print STDERR ref($cloud)."..\n";
+       if (ref $cloud eq 'HTML::TagCloud') {
+               return $cloud->html_and_css($count);
+       } else {
+               my @tags = sort { $cloud->{$a}->{count} <=> $cloud->{$b}->{count} } keys %$cloud;
+               return '<p align="center">' . join (', ', map {
+                       "<a href=\"$home_link?by_tag=$_\">$cloud->{$_}->{topname}</a>"
+               } splice(@tags, 0, $count)) . '</p>';
+       }
+}
+
 sub git_get_project_url_list {
        my $path = shift;
 
@@ -3580,6 +3659,7 @@ sub fill_project_list_info {
        my ($projlist, $check_forks) = @_;
        my @projects;
 
+       my $show_ctags = gitweb_check_feature('ctags');
  PROJECT:
        foreach my $pr (@$projlist) {
                my (@activity) = git_get_last_activity($pr->{'path'});
@@ -3606,6 +3686,7 @@ sub fill_project_list_info {
                                $pr->{'forks'} = 0;
                        }
                }
+               $show_ctags and $pr->{'ctags'} = git_get_project_ctags($pr->{'path'});
                push @projects, $pr;
        }
 
@@ -3652,6 +3733,18 @@ sub git_project_list_body {
        $from = 0 unless defined $from;
        $to = $#projects if (!defined $to || $#projects < $to);
 
+       my $show_ctags = gitweb_check_feature('ctags');
+       if ($show_ctags) {
+               my %ctags;
+               foreach my $p (@projects) {
+                       foreach my $ct (keys %{$p->{'ctags'}}) {
+                               $ctags{$ct} += $p->{'ctags'}->{$ct};
+                       }
+               }
+               my $cloud = git_populate_project_tagcloud(\%ctags);
+               print git_show_project_tagcloud($cloud, 64);
+       }
+
        print "<table class=\"project_list\">\n";
        unless ($no_header) {
                print "<tr>\n";
@@ -3670,8 +3763,10 @@ sub git_project_list_body {
                      "</tr>\n";
        }
        my $alternate = 1;
+       my $tagfilter = $cgi->param('by_tag');
        for (my $i = $from; $i <= $to; $i++) {
                my $pr = $projects[$i];
+               next if $tagfilter and $show_ctags and not grep { lc $_ eq lc $tagfilter } keys %{$pr->{'ctags'}};
                if ($alternate) {
                        print "<tr class=\"dark\">\n";
                } else {
@@ -4093,6 +4188,20 @@ sub git_summary {
                print "<tr class=\"metadata_url\"><td>$url_tag</td><td>$git_url</td></tr>\n";
                $url_tag = "";
        }
+
+       # Tag cloud
+       my $show_ctags = (gitweb_check_feature('ctags'))[0];
+       if ($show_ctags) {
+               my $ctags = git_get_project_ctags($project);
+               my $cloud = git_populate_project_tagcloud($ctags);
+               print "<tr id=\"metadata_ctags\"><td>Content tags:<br />";
+               print "</td>\n<td>" unless %$ctags;
+               print "<form action=\"$show_ctags\" method=\"post\"><input type=\"hidden\" name=\"p\" value=\"$project\" />Add: <input type=\"text\" name=\"t\" size=\"8\" /></form>";
+               print "</td>\n<td>" if %$ctags;
+               print git_show_project_tagcloud($cloud, 48);
+               print "</td></tr>";
+       }
+
        print "</table>\n";
 
        if (-s "$projectroot/$project/README.html") {