graphviz: Support urls embedded in the graph, by having graphviz generate an imagemap.

[ikiwiki.git] / IkiWiki / Plugin / graphviz.pm

diff --git a/IkiWiki/Plugin/graphviz.pm b/IkiWiki/Plugin/graphviz.pm
index b43e96a73adad4b1b8091c689110c70611a983f6..f01fdca8573135026210468ac2b84ae63806f7b5 100644 (file)
--- a/IkiWiki/Plugin/graphviz.pm
+++ b/IkiWiki/Plugin/graphviz.pm
@@ -18,6 +18,7 @@ sub getsetup () {
                plugin => {
                        safe => 1,
                        rebuild => undef,
+                       section => "widget",
                },
 }
 
@@ -25,10 +26,13 @@ my %graphviz_programs = (
        "dot" => 1, "neato" => 1, "fdp" => 1, "twopi" => 1, "circo" => 1
 );
 
+my $graphnum=0;
+
 sub render_graph (\%) {
        my %params = %{(shift)};
 
-       my $src = "$params{type} g {\n";
+       $graphnum++;
+       my $src = "$params{type} graph$graphnum {\n";
        $src .= "charset=\"utf-8\";\n";
        $src .= "ratio=compress;\nsize=\"".($params{width}+0).", ".($params{height}+0)."\";\n"
                if defined $params{width} and defined $params{height};
@@ -36,54 +40,52 @@ sub render_graph (\%) {
        $src .= "}\n";
 
        # Use the sha1 of the graphviz code as part of its filename.
-       eval q{use Digest::SHA1};
+       eval q{use Digest::SHA};
        error($@) if $@;
-       my $dest=$params{page}."/graph-".
-               IkiWiki::possibly_foolish_untaint(Digest::SHA1::sha1_hex($src)).
-               ".png";
+       my $base=$params{page}."/graph-".
+               IkiWiki::possibly_foolish_untaint(Digest::SHA::sha1_hex($src));
+       my $dest=$base.".png";
        will_render($params{page}, $dest);
 
-       if (! -e "$config{destdir}/$dest") {
+       # The imagemap data is stored as a separate file.
+       my $imagemap=$base.".imagemap";
+       will_render($params{page}, $imagemap);
+       
+       my $map;
+       if (! -e "$config{destdir}/$dest" || ! -e "$config{destdir}/$imagemap") {
+               # Use ikiwiki's function to create the image file, this makes
+               # sure needed subdirs are there and does some sanity checking.
+               writefile($dest, $config{destdir}, "");
+               
                my $pid;
-               my $sigpipe=0;;
+               my $sigpipe=0;
                $SIG{PIPE}=sub { $sigpipe=1 };
-               $pid=open2(*IN, *OUT, "$params{prog} -Tpng");
+               $pid=open2(*IN, *OUT, "$params{prog} -Tpng -o '$config{destdir}/$dest' -Tcmapx");
 
                # open2 doesn't respect "use open ':utf8'"
+               binmode (IN, ':utf8');
                binmode (OUT, ':utf8');
 
                print OUT $src;
                close OUT;
 
-               my $png;
-               {
-                       local $/ = undef;
-                       $png = <IN>;
-               }
+               local $/ = undef;
+               $map=<IN>;
                close IN;
+               writefile($imagemap, $config{destdir}, $map);
 
                waitpid $pid, 0;
                $SIG{PIPE}="DEFAULT";
-               error gettext("failed to run graphviz") if $sigpipe;
-
-               if (! $params{preview}) {
-                       writefile($dest, $config{destdir}, $png, 1);
-               }
-               else {
-                       # can't write the file, so embed it in a data uri
-                       eval q{use MIME::Base64};
-                       error($@) if $@;
-                       return "<img src=\"data:image/png;base64,".
-                               encode_base64($png)."\" />";
-               }
-       }
+               error gettext("failed to run graphviz") if ($sigpipe || $?);
 
-       if ($params{preview}) {
-               return "<img src=\"".urlto($dest, "")."\" />\n";
        }
        else {
-               return "<img src=\"".urlto($dest, $params{destpage})."\" />\n";
+               $map=readfile("$config{destdir}/$imagemap");
        }
+
+       return "<img src=\"".urlto($dest, $params{destpage}).
+               "\" usemap=\"#graph$graphnum\" />\n".
+               $map;
 }
 
 sub graph (@) {