store imagemap in %pagestate, rather than a file

Using a file was sorta not right.

Note that when previewing, %pagestate is not saved, so
it has to rebuild the graph every time until that graph is saved;
then previews can use the cached data until the next time the graph
is changed.

Also note that it's stored in the destpage's pagestate. The imagemap
could vary between a page and an inlined page if wikilinks were supported.

diff --git a/IkiWiki/Plugin/graphviz.pm b/IkiWiki/Plugin/graphviz.pm
index f01fdca8573135026210468ac2b84ae63806f7b5..4268f42ed29a70a43f2df74c273adca74555c37c 100644 (file)
--- a/IkiWiki/Plugin/graphviz.pm
+++ b/IkiWiki/Plugin/graphviz.pm
@@ -10,6 +10,7 @@ use IPC::Open2;
 
 sub import {
        hook(type => "getsetup", id => "graphviz", call => \&getsetup);
+       hook(type => "needsbuild", id => "version", call => \&needsbuild);
        hook(type => "preprocess", id => "graph", call => \&graph);
 }
 
@@ -26,33 +27,41 @@ my %graphviz_programs = (
        "dot" => 1, "neato" => 1, "fdp" => 1, "twopi" => 1, "circo" => 1
 );
 
-my $graphnum=0;
+sub needsbuild {
+       my $needsbuild=shift;
+       foreach my $page (keys %pagestate) {
+               if (exists $pagestate{$page}{graph} &&
+                   exists $pagesources{$page} &&
+                   grep { $_ eq $pagesources{$page} } @$needsbuild) {
+                       # remove state, will be re-added if
+                       # the graph is still there during the rebuild
+                       delete $pagestate{$page}{graph};
+               }
+       }       
+       return $needsbuild;
+}
 
 sub render_graph (\%) {
        my %params = %{(shift)};
-
-       $graphnum++;
-       my $src = "$params{type} graph$graphnum {\n";
-       $src .= "charset=\"utf-8\";\n";
+       
+       my $src = "charset=\"utf-8\";\n";
        $src .= "ratio=compress;\nsize=\"".($params{width}+0).", ".($params{height}+0)."\";\n"
                if defined $params{width} and defined $params{height};
        $src .= $params{src};
        $src .= "}\n";
-
-       # Use the sha1 of the graphviz code as part of its filename.
+       
+       # Use the sha1 of the graphviz code as part of its filename,
+       # and as a unique identifier for its imagemap.
        eval q{use Digest::SHA};
        error($@) if $@;
-       my $base=$params{page}."/graph-".
-               IkiWiki::possibly_foolish_untaint(Digest::SHA::sha1_hex($src));
-       my $dest=$base.".png";
+       my $sha=IkiWiki::possibly_foolish_untaint(Digest::SHA::sha1_hex($params{type}.$src));
+       $src = "$params{type} graph$sha {\n".$src;
+
+       my $dest=$params{page}."/graph-".$sha.".png";
        will_render($params{page}, $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") {
+       my $map=$pagestate{$params{destpage}}{graph}{$sha};
+       if (! -e "$config{destdir}/$dest" || ! defined $map) {
                # Use ikiwiki's function to create the image file, this makes
                # sure needed subdirs are there and does some sanity checking.
                writefile($dest, $config{destdir}, "");
@@ -70,21 +79,16 @@ sub render_graph (\%) {
                close OUT;
 
                local $/ = undef;
-               $map=<IN>;
+               $map=$pagestate{$params{destpage}}{graph}{$sha}=<IN>;
                close IN;
-               writefile($imagemap, $config{destdir}, $map);
 
                waitpid $pid, 0;
                $SIG{PIPE}="DEFAULT";
                error gettext("failed to run graphviz") if ($sigpipe || $?);
-
-       }
-       else {
-               $map=readfile("$config{destdir}/$imagemap");
        }
 
        return "<img src=\"".urlto($dest, $params{destpage}).
-               "\" usemap=\"#graph$graphnum\" />\n".
+               "\" usemap=\"#graph$sha\" />\n".
                $map;
 }