IkiWiki/Plugin/search.pm

   1 #!/usr/bin/perl
   2 # xapian-omega search engine plugin
   3 package IkiWiki::Plugin::search;
   4
   5 use warnings;
   6 use strict;
   7 use IkiWiki 3.00;
   8
   9 sub import {
  10         hook(type => "getsetup", id => "search", call => \&getsetup);
  11         hook(type => "checkconfig", id => "search", call => \&checkconfig);
  12         hook(type => "pagetemplate", id => "search", call => \&pagetemplate);
  13         hook(type => "indexhtml", id => "search", call => \&indexhtml);
  14         hook(type => "delete", id => "search", call => \&delete);
  15         hook(type => "cgi", id => "search", call => \&cgi);
  16         hook(type => "disable", id => "search", call => \&disable);
  17         hook(type => "needsbuild", id => "search", call => \&needsbuild);
  18
  19         eval q{ use Search::Xapian }; # load early to work around #622591
  20 }
  21
  22 sub getsetup () {
  23         return
  24                 plugin => {
  25                         safe => 1,
  26                         rebuild => 1,
  27                         section => "web",
  28                 },
  29                 omega_cgi => {
  30                         type => "string",
  31                         example => "/usr/lib/cgi-bin/omega/omega",
  32                         description => "path to the omega cgi program",
  33                         safe => 0, # external program
  34                         rebuild => 0,
  35                 },
  36 }
  37
  38 sub checkconfig () {
  39         foreach my $required (qw(url cgiurl)) {
  40                 if (! length $config{$required}) {
  41                         error(sprintf(gettext("Must specify %s when using the %s plugin"), $required, 'search'));
  42                 }
  43         }
  44
  45         if (! defined $config{omega_cgi}) {
  46                 $config{omega_cgi}="/usr/lib/cgi-bin/omega/omega";
  47         }
  48
  49         # This is a mass dependency, so if the search form template
  50         # changes, every page is rebuilt.
  51         add_depends("", "templates/searchform.tmpl");
  52 }
  53
  54 my $form;
  55 sub pagetemplate (@) {
  56         my %params=@_;
  57         my $page=$params{page};
  58         my $template=$params{template};
  59
  60         # Add search box to page header.
  61         if ($template->query(name => "searchform")) {
  62                 if (! defined $form) {
  63                         my $searchform = template("searchform.tmpl", blind_cache => 1);
  64                         $searchform->param(searchaction => IkiWiki::cgiurl());
  65                         $searchform->param(html5 => $config{html5});
  66                         $form=$searchform->output;
  67                 }
  68
  69                 $template->param(searchform => $form);
  70         }
  71 }
  72
  73 my $scrubber;
  74 my $stemmer;
  75 sub indexhtml (@) {
  76         my %params=@_;
  77
  78         setupfiles();
  79
  80         # A unique pageterm is used to identify the document for a page.
  81         my $pageterm=pageterm($params{page});
  82         return unless defined $pageterm;
  83
  84         my $db=xapiandb();
  85         my $doc=Search::Xapian::Document->new();
  86         my $caption=pagetitle($params{page});
  87         my $title;
  88         if (exists $pagestate{$params{page}}{meta} &&
  89                 exists $pagestate{$params{page}}{meta}{title}) {
  90                 $title=$pagestate{$params{page}}{meta}{title};
  91         }
  92         else {
  93                 $title=$caption;
  94         }
  95
  96         # Remove html from text to be indexed.
  97         if (! defined $scrubber) {
  98                 eval q{use HTML::Scrubber};
  99                 if (! $@) {
 100                         $scrubber=HTML::Scrubber->new(allow => []);
 101                 }
 102         }
 103         my $toindex = defined $scrubber ? $scrubber->scrub($params{content}) : $params{content};
 104
 105         # Take 512 characters for a sample, then extend it out
 106         # if it stopped in the middle of a word.
 107         my $size=512;
 108         my ($sample)=substr($toindex, 0, $size);
 109         if (length($sample) == $size) {
 110                 my $max=length($toindex);
 111                 my $next;
 112                 while ($size < $max &&
 113                        ($next=substr($toindex, $size++, 1)) !~ /\s/) {
 114                         $sample.=$next;
 115                 }
 116         }
 117         $sample=~s/\n/ /g;
 118
 119         my $url=urlto($params{destpage}, "");
 120         if (defined $pagestate{$params{page}}{meta}{permalink}) {
 121                 $url=$pagestate{$params{page}}{meta}{permalink}
 122         }
 123
 124         # data used by omega
 125         # Decode html entities in it, since omega re-encodes them.
 126         eval q{use HTML::Entities};
 127         error $@ if $@;
 128         $doc->set_data(
 129                 "url=".$url."\n".
 130                 "sample=".decode_entities($sample)."\n".
 131                 "caption=".decode_entities($caption)."\n".
 132                 "modtime=$IkiWiki::pagemtime{$params{page}}\n".
 133                 "size=".length($params{content})."\n"
 134         );
 135
 136         # Index document and add terms for other metadata.
 137         my $tg = Search::Xapian::TermGenerator->new();
 138         if (! $stemmer) {
 139                 my $langcode=$ENV{LANG} || "en";
 140                 $langcode=~s/_.*//;
 141
 142                 # This whitelist is here to work around a xapian bug (#486138)
 143                 my @whitelist=qw{da de en es fi fr hu it no pt ru ro sv tr};
 144
 145                 if (grep { $_ eq $langcode } @whitelist) {
 146                         $stemmer=Search::Xapian::Stem->new($langcode);
 147                 }
 148                 else {
 149                         $stemmer=Search::Xapian::Stem->new("english");
 150                 }
 151         }
 152         $tg->set_stemmer($stemmer);
 153         $tg->set_document($doc);
 154         $tg->index_text($params{page}, 2);
 155         $tg->index_text($caption, 2);
 156         $tg->index_text($title, 2) if $title ne $caption;
 157         $tg->index_text($toindex);
 158         $tg->index_text(lc($title), 1, "S"); # for title:foo
 159         foreach my $link (@{$links{$params{page}}}) {
 160                 $tg->index_text(lc($link), 1, "XLINK"); # for link:bar
 161         }
 162
 163         $doc->add_term($pageterm);
 164         $db->replace_document_by_term($pageterm, $doc);
 165 }
 166
 167 sub delete (@) {
 168         my $db=xapiandb();
 169         foreach my $page (@_) {
 170                 my $pageterm=pageterm(pagename($page));
 171                 $db->delete_document_by_term($pageterm) if defined $pageterm;
 172         }
 173 }
 174
 175 sub cgi ($) {
 176         my $cgi=shift;
 177
 178         if (defined $cgi->param('P')) {
 179                 # only works for GET requests
 180                 chdir("$config{wikistatedir}/xapian") || error("chdir: $!");
 181                 $ENV{OMEGA_CONFIG_FILE}="./omega.conf";
 182                 $ENV{CGIURL}=IkiWiki::cgiurl();
 183                 IkiWiki::loadindex();
 184                 $ENV{HELPLINK}=htmllink("", "", "ikiwiki/searching",
 185                         noimageinline => 1, linktext => "Help");
 186                 exec($config{omega_cgi}) || error("$config{omega_cgi} failed: $!");
 187         }
 188 }
 189
 190 sub pageterm ($) {
 191         my $page=shift;
 192
 193         # 240 is the number used by omindex to decide when to hash an
 194         # overlong term. This does not use a compatible hash method though.
 195         if (length $page > 240) {
 196                 eval q{use Digest::SHA};
 197                 if ($@) {
 198                         debug("search: ".sprintf(gettext("need Digest::SHA to index %s"), $page)) if $@;
 199                         return undef;
 200                 }
 201
 202                 # Note no colon, therefore it's guaranteed to not overlap
 203                 # with a page with the same name as the hash..
 204                 return "U".lc(Digest::SHA::sha1_hex($page));
 205         }
 206         else {
 207                 return "U:".$page;
 208         }
 209 }
 210
 211 my $db;
 212 sub xapiandb () {
 213         if (! defined $db) {
 214                 eval q{
 215                         use Search::Xapian;
 216                         use Search::Xapian::WritableDatabase;
 217                 };
 218                 error($@) if $@;
 219                 $db=Search::Xapian::WritableDatabase->new($config{wikistatedir}."/xapian/default",
 220                         Search::Xapian::DB_CREATE_OR_OPEN());
 221         }
 222         return $db;
 223 }
 224
 225 {
 226 my $setup=0;
 227 sub setupfiles () {
 228         if (! $setup and (! -e $config{wikistatedir}."/xapian" || $config{rebuild})) {
 229                 writefile("omega.conf", $config{wikistatedir}."/xapian",
 230                         "database_dir .\n".
 231                         "template_dir ./templates\n");
 232                 omega_template();
 233                 $setup=1;
 234         }
 235 }
 236 }
 237
 238 sub needsbuild {
 239         my $list=shift;
 240         if (grep {
 241                 $_ eq "templates/page.tmpl" ||
 242                 $_ eq "templates/searchquery.tmpl"
 243         } @$list) {
 244                 omega_template();
 245         }
 246 }
 247
 248 sub omega_template {
 249         # Avoid omega interpreting anything in the cgitemplate
 250         # as an omegascript command.
 251         eval q{use IkiWiki::CGI};
 252         my $template=IkiWiki::cgitemplate(undef, gettext("search"), "\0",
 253                 searchform => "", # avoid showing the small search form
 254         );
 255         eval q{use HTML::Entities};
 256         error $@ if $@;
 257         $template=encode_entities($template, '\$');
 258
 259         my $querytemplate=readfile(IkiWiki::template_file("searchquery.tmpl"));
 260         $template=~s/\0/$querytemplate/;
 261         writefile("query", $config{wikistatedir}."/xapian/templates",
 262                 $template);
 263 }
 264
 265 sub disable () {
 266         if (-d $config{wikistatedir}."/xapian") {
 267                 system("rm", "-rf", $config{wikistatedir}."/xapian");
 268         }
 269 }
 270
 271 1