IkiWiki/Plugin/graphviz.pm

   1 #!/usr/bin/perl
   2 # graphviz plugin for ikiwiki: render graphviz source as an image.
   3 # Josh Triplett
   4 package IkiWiki::Plugin::graphviz;
   5
   6 use warnings;
   7 use strict;
   8 use IkiWiki 3.00;
   9 use IPC::Open2;
  10
  11 sub import {
  12         hook(type => "getsetup", id => "graphviz", call => \&getsetup);
  13         hook(type => "needsbuild", id => "version", call => \&needsbuild);
  14         hook(type => "preprocess", id => "graph", call => \&graph, scan => 1);
  15 }
  16
  17 sub getsetup () {
  18         return
  19                 plugin => {
  20                         safe => 1,
  21                         rebuild => undef,
  22                         section => "widget",
  23                 },
  24 }
  25
  26 my %graphviz_programs = (
  27         "dot" => 1, "neato" => 1, "fdp" => 1, "twopi" => 1, "circo" => 1
  28 );
  29
  30 sub needsbuild {
  31         my $needsbuild=shift;
  32         foreach my $page (keys %pagestate) {
  33                 if (exists $pagestate{$page}{graph} &&
  34                     exists $pagesources{$page} &&
  35                     grep { $_ eq $pagesources{$page} } @$needsbuild) {
  36                         # remove state, will be re-added if
  37                         # the graph is still there during the rebuild
  38                         delete $pagestate{$page}{graph};
  39                 }
  40         }
  41         return $needsbuild;
  42 }
  43
  44 sub render_graph (\%) {
  45         my %params = %{(shift)};
  46
  47         my $src = "charset=\"utf-8\";\n";
  48         $src .= "ratio=compress;\nsize=\"".($params{width}+0).", ".($params{height}+0)."\";\n"
  49                 if defined $params{width} and defined $params{height};
  50         $src .= $params{src};
  51         $src .= "}\n";
  52
  53         # Use the sha1 of the graphviz code as part of its filename,
  54         # and as a unique identifier for its imagemap.
  55         eval q{use Digest::SHA};
  56         error($@) if $@;
  57         my $sha=IkiWiki::possibly_foolish_untaint(Digest::SHA::sha1_hex($params{type}.$src));
  58         $src = "$params{type} graph$sha {\n".$src;
  59
  60         my $dest=$params{page}."/graph-".$sha.".png";
  61         will_render($params{page}, $dest);
  62
  63         my $map=$pagestate{$params{destpage}}{graph}{$sha};
  64         if (! -e "$config{destdir}/$dest" || ! defined $map) {
  65                 # Use ikiwiki's function to create the image file, this makes
  66                 # sure needed subdirs are there and does some sanity checking.
  67                 writefile($dest, $config{destdir}, "");
  68
  69                 my $pid;
  70                 my $sigpipe=0;
  71                 $SIG{PIPE}=sub { $sigpipe=1 };
  72                 $pid=open2(*IN, *OUT, "$params{prog} -Tpng -o '$config{destdir}/$dest' -Tcmapx");
  73
  74                 # open2 doesn't respect "use open ':utf8'"
  75                 binmode (IN, ':utf8');
  76                 binmode (OUT, ':utf8');
  77
  78                 print OUT $src;
  79                 close OUT;
  80
  81                 local $/ = undef;
  82                 $map=$pagestate{$params{destpage}}{graph}{$sha}=<IN>;
  83                 close IN;
  84
  85                 waitpid $pid, 0;
  86                 $SIG{PIPE}="DEFAULT";
  87                 error gettext("failed to run graphviz") if ($sigpipe || $?);
  88         }
  89
  90         return "<img src=\"".urlto($dest, $params{destpage}).
  91                 "\" usemap=\"#graph$sha\" />\n".
  92                 $map;
  93 }
  94
  95 sub graph (@) {
  96         my %params=@_;
  97
  98         # Support wikilinks in the graph source.
  99         my $src=$params{src};
 100         $src="" unless defined $src;
 101         $src=IkiWiki::linkify($params{page}, $params{destpage}, $params{src});
 102         return unless defined wantarray; # scan mode short-circuit
 103         if ($src ne $params{src}) {
 104                 # linkify makes html links, but graphviz wants plain
 105                 # urls. This is, frankly a hack: Process source as html,
 106                 # throw out everything inside tags that is not a href.
 107                 my $s;
 108                 my $nested=0;
 109                 use HTML::Parser;
 110                 error $@ if $@;
 111                 my $p=HTML::Parser->new(api_version => 3);
 112                 $p->handler(start => sub {
 113                         my %attrs=%{shift()};
 114                         if (exists $attrs{href}) {
 115                                 if ($s=~/href\s*=\s*"$/) {
 116                                         $s.=$attrs{href};
 117                                 }
 118                                 elsif ($s=~/href\s*=\s*$/) {
 119                                         $s.="\"$attrs{href}\"";
 120                                 }
 121                                 else {
 122                                         $s.="href=\"$attrs{href}\"";
 123                                 }
 124                         }
 125                         $nested++;
 126                 }, "attr");
 127                 $p->handler(end => sub {
 128                         $nested--;
 129                 });
 130                 $p->handler(default => sub {
 131                         $s.=join("", @_) unless $nested;
 132                 }, "text");
 133                 $p->parse($src);
 134                 $p->eof;
 135                 $params{src}=$s;
 136         }
 137         else {
 138                 $params{src}=$src;
 139         }
 140
 141         $params{type} = "digraph" unless defined $params{type};
 142         $params{prog} = "dot" unless defined $params{prog};
 143         error gettext("prog not a valid graphviz program") unless $graphviz_programs{$params{prog}};
 144
 145         return render_graph(%params);
 146 }
 147
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