ikiwiki/IkiWiki/Plugin/search.pm

209 lines
5.4 KiB
Perl

#!/usr/bin/perl
# xapian-omega search engine plugin
package IkiWiki::Plugin::search;
use warnings;
use strict;
use IkiWiki 2.00;
sub import { #{{{
hook(type => "checkconfig", id => "search", call => \&checkconfig);
hook(type => "pagetemplate", id => "search", call => \&pagetemplate);
hook(type => "postscan", id => "search", call => \&index);
hook(type => "delete", id => "search", call => \&delete);
hook(type => "cgi", id => "search", call => \&cgi);
} # }}}
sub checkconfig () { #{{{
foreach my $required (qw(url cgiurl)) {
if (! length $config{$required}) {
error(sprintf(gettext("Must specify %s when using the search plugin"), $required));
}
}
if (! exists $config{omega_cgi}) {
$config{omega_cgi}="/usr/lib/cgi-bin/omega/omega";
}
} #}}}
my $form;
sub pagetemplate (@) { #{{{
my %params=@_;
my $page=$params{page};
my $template=$params{template};
# Add search box to page header.
if ($template->query(name => "searchform")) {
if (! defined $form) {
my $searchform = template("searchform.tmpl", blind_cache => 1);
$searchform->param(searchaction => $config{cgiurl});
$form=$searchform->output;
}
$template->param(searchform => $form);
}
} #}}}
my $scrubber;
my $stemmer;
sub index (@) { #{{{
my %params=@_;
setupfiles();
# A unique pageterm is used to identify the document for a page.
my $pageterm=pageterm($params{page});
return $params{content} unless defined $pageterm;
my $db=xapiandb();
my $doc=Search::Xapian::Document->new();
my $caption=IkiWiki::pagetitle($params{page});
my $title;
if (exists $pagestate{$params{page}}{meta} &&
exists $pagestate{$params{page}}{meta}{title}) {
$title=$pagestate{$params{page}}{meta}{title};
}
else {
$title=$caption;
}
# Remove html from text to be indexed.
if (! defined $scrubber) {
eval q{use HTML::Scrubber};
if (! $@) {
$scrubber=HTML::Scrubber->new(allow => []);
}
}
my $toindex = defined $scrubber ? $scrubber->scrub($params{content}) : $params{content};
# Take 512 characters for a sample, then extend it out
# if it stopped in the middle of a word.
my $size=512;
my ($sample)=substr($toindex, 0, $size);
if (length($sample) == $size) {
my $max=length($toindex);
my $next;
while ($size < $max &&
($next=substr($toindex, $size++, 1)) !~ /\s/) {
$sample.=$next;
}
}
$sample=~s/\n/ /g;
# data used by omega
# Decode html entities in it, since omega re-encodes them.
eval q{use HTML::Entities};
$doc->set_data(
"url=".urlto($params{page}, "")."\n".
"sample=".decode_entities($sample)."\n".
"caption=".decode_entities($caption)."\n".
"modtime=$IkiWiki::pagemtime{$params{page}}\n".
"size=".length($params{content})."\n"
);
# Index document and add terms for other metadata.
my $tg = Search::Xapian::TermGenerator->new();
if (! $stemmer) {
my $langcode=$ENV{LANG} || "en";
$langcode=~s/_.*//;
# This whitelist is here to work around a xapian bug (#486138)
my @whitelist=qw{da de en es fi fr hu it no pt ru ro sv tr};
if (grep { $_ eq $langcode } @whitelist) {
$stemmer=Search::Xapian::Stem->new($langcode);
}
else {
$stemmer=Search::Xapian::Stem->new("english");
}
}
$tg->set_stemmer($stemmer);
$tg->set_document($doc);
$tg->index_text($params{page}, 2);
$tg->index_text($caption, 2);
$tg->index_text($title, 2) if $title ne $caption;
$tg->index_text($toindex);
$tg->index_text(lc($title), 1, "S"); # for title:foo
foreach my $link (@{$links{$params{page}}}) {
$tg->index_text(lc($link), 1, "XLINK"); # for link:bar
}
$doc->add_term($pageterm);
$db->replace_document_by_term($pageterm, $doc);
} #}}}
sub delete (@) { #{{{
my $db=xapiandb();
foreach my $page (@_) {
my $pageterm=pageterm(pagename($page));
$db->delete_document_by_term($pageterm) if defined $pageterm;
}
} #}}}
sub cgi ($) { #{{{
my $cgi=shift;
if (defined $cgi->param('P')) {
# only works for GET requests
chdir("$config{wikistatedir}/xapian") || error("chdir: $!");
$ENV{OMEGA_CONFIG_FILE}="./omega.conf";
$ENV{CGIURL}=$config{cgiurl},
IkiWiki::loadindex();
$ENV{HELPLINK}=htmllink("", "", "ikiwiki/searching",
noimageinline => 1, linktext => "Help");
exec($config{omega_cgi}) || error("$config{omega_cgi} failed: $!");
}
} #}}}
sub pageterm ($) { #{{{
my $page=shift;
# 240 is the number used by omindex to decide when to hash an
# overlong term. This does not use a compatible hash method though.
if (length $page > 240) {
eval q{use Digest::SHA1};
if ($@) {
debug("search: ".sprintf(gettext("need Digest::SHA1 to index %s"), $page)) if $@;
return undef;
}
# Note no colon, therefore it's guaranteed to not overlap
# with a page with the same name as the hash..
return "U".lc(Digest::SHA1::sha1_hex($page));
}
else {
return "U:".$page;
}
} #}}}
my $db;
sub xapiandb () { #{{{
if (! defined $db) {
eval q{
use Search::Xapian;
use Search::Xapian::WritableDatabase;
};
error($@) if $@;
$db=Search::Xapian::WritableDatabase->new($config{wikistatedir}."/xapian/default",
Search::Xapian::DB_CREATE_OR_OPEN());
}
return $db;
} #}}}
{
my $setup=0;
sub setupfiles () { #{{{
if (! $setup and (! -e $config{wikistatedir}."/xapian" || $config{rebuild})) {
writefile("omega.conf", $config{wikistatedir}."/xapian",
"database_dir .\n".
"template_dir ./templates\n");
writefile("query", $config{wikistatedir}."/xapian/templates",
IkiWiki::misctemplate(gettext("search"),
readfile(IkiWiki::template_file("searchquery.tmpl"))));
$setup=1;
}
} #}}}
}
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