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