1#!/usr/bin/perl
2# xapian-omega search engine plugin
3package IkiWiki::Plugin::search;
4
5use warnings;
6use strict;
7use IkiWiki 3.00;
8
9sub 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
22sub getsetup () {
23	return
24		plugin => {
25			safe => 1,
26			rebuild => 1,
27			section => "web",
28		},
29		omega_cgi => {
30			type => "string",
31			example => "/usr/local/www/xapian-omega/cgi-bin/omega",
32			description => "path to the omega cgi program",
33			safe => 0, # external program
34			rebuild => 0,
35		},
36		google_search => {
37			type => "boolean",
38			example => 1,
39			description => "use google site search rather than internal xapian index?",
40			safe => 1,
41			rebuild => 0,
42		},
43}
44
45sub checkconfig () {
46	foreach my $required (qw(url cgiurl)) {
47		if (! length $config{$required}) {
48			error(sprintf(gettext("Must specify %s when using the %s plugin"), $required, 'search'));
49		}
50	}
51
52	if (! defined $config{omega_cgi}) {
53		$config{omega_cgi}="/usr/local/www/xapian-omega/cgi-bin/omega";
54	}
55
56	# This is a mass dependency, so if the search form template
57	# changes, every page is rebuilt.
58	add_depends("", "templates/searchform.tmpl");
59}
60
61my $form;
62sub pagetemplate (@) {
63	my %params=@_;
64	my $page=$params{page};
65	my $template=$params{template};
66
67	# Add search box to page header.
68	if ($template->query(name => "searchform")) {
69		if (! defined $form) {
70			my $searchform = template("searchform.tmpl", blind_cache => 1);
71			$searchform->param(searchaction => IkiWiki::cgiurl());
72			$searchform->param(html5 => $config{html5});
73			$form=$searchform->output;
74		}
75
76		$template->param(searchform => $form);
77	}
78}
79
80my $scrubber;
81my $stemmer;
82sub indexhtml (@) {
83	my %params=@_;
84
85	return if $config{google_search};
86
87	setupfiles();
88
89	# A unique pageterm is used to identify the document for a page.
90	my $pageterm=pageterm($params{page});
91	return unless defined $pageterm;
92
93	my $db=xapiandb();
94	my $doc=Search::Xapian::Document->new();
95	my $caption=pagetitle($params{page});
96	my $title;
97	if (exists $pagestate{$params{page}}{meta} &&
98		exists $pagestate{$params{page}}{meta}{title}) {
99		$title=$pagestate{$params{page}}{meta}{title};
100	}
101	else {
102		$title=$caption;
103	}
104
105	# Remove html from text to be indexed.
106	if (! defined $scrubber) {
107		eval q{use HTML::Scrubber};
108		if (! $@) {
109			$scrubber=HTML::Scrubber->new(allow => []);
110		}
111	}
112	my $toindex = defined $scrubber ? $scrubber->scrub($params{content}) : $params{content};
113
114	# Take 512 characters for a sample, then extend it out
115	# if it stopped in the middle of a word.
116	my $size=512;
117	my ($sample)=substr($toindex, 0, $size);
118	if (length($sample) == $size) {
119		my $max=length($toindex);
120		my $next;
121		while ($size < $max &&
122		       ($next=substr($toindex, $size++, 1)) !~ /\s/) {
123			$sample.=$next;
124		}
125	}
126	$sample=~s/\n/ /g;
127
128	my $url=urlto($params{destpage}, "");
129	if (defined $pagestate{$params{page}}{meta}{permalink}) {
130		$url=$pagestate{$params{page}}{meta}{permalink}
131	}
132
133	# data used by omega
134	# Decode html entities in it, since omega re-encodes them.
135	eval q{use HTML::Entities};
136	error $@ if $@;
137	$doc->set_data(
138		"url=".$url."\n".
139		"sample=".decode_entities($sample)."\n".
140		"caption=".decode_entities($caption)."\n".
141		"modtime=$IkiWiki::pagemtime{$params{page}}\n".
142		"size=".length($params{content})."\n"
143	);
144
145	# Index document and add terms for other metadata.
146	my $tg = Search::Xapian::TermGenerator->new();
147	if (! $stemmer) {
148		my $langcode=$ENV{LANG} || "en";
149		$langcode=~s/_.*//;
150
151		# This whitelist is here to work around a xapian bug (#486138)
152		my @whitelist=qw{da de en es fi fr hu it no pt ru ro sv tr};
153
154		if (grep { $_ eq $langcode } @whitelist) {
155			$stemmer=Search::Xapian::Stem->new($langcode);
156		}
157		else {
158			$stemmer=Search::Xapian::Stem->new("english");
159		}
160	}
161	$tg->set_stemmer($stemmer);
162	$tg->set_document($doc);
163	$tg->index_text($params{page}, 2);
164	$tg->index_text($caption, 2);
165	$tg->index_text($title, 2) if $title ne $caption;
166	$tg->index_text($toindex);
167	$tg->index_text(lc($title), 1, "S"); # for title:foo
168	foreach my $link (@{$links{$params{page}}}) {
169		$tg->index_text(lc($link), 1, "XLINK"); # for link:bar
170	}
171
172	$doc->add_term($pageterm);
173	$db->replace_document_by_term($pageterm, $doc);
174}
175
176sub delete (@) {
177	return if $config{google_search};
178
179	my $db=xapiandb();
180	foreach my $page (@_) {
181		my $pageterm=pageterm(pagename($page));
182		$db->delete_document_by_term($pageterm) if defined $pageterm;
183	}
184}
185
186sub cgi ($) {
187	my $cgi=shift;
188
189	if (defined $cgi->param('P')) {
190		if ($config{google_search}) {
191			print $cgi->redirect("https://www.google.com/search?sitesearch=$config{url}&q=".$cgi->param('P'));
192			exit 0;
193		}
194		else {
195			# only works for GET requests
196			chdir("$config{wikistatedir}/xapian") || error("chdir: $!");
197			$ENV{OMEGA_CONFIG_FILE}="./omega.conf";
198			$ENV{CGIURL}=IkiWiki::cgiurl();
199			IkiWiki::loadindex();
200			$ENV{HELPLINK}=htmllink("", "", "ikiwiki/searching",
201				noimageinline => 1, linktext => "Help");
202			exec($config{omega_cgi}) || error("$config{omega_cgi} failed: $!");
203		}
204	}
205}
206
207sub pageterm ($) {
208	my $page=shift;
209
210	# 240 is the number used by omindex to decide when to hash an
211	# overlong term. This does not use a compatible hash method though.
212	eval q{use Encode};
213	if (length encode_utf8($page) > 240) {
214		eval q{use Digest::SHA};
215		if ($@) {
216			debug("search: ".sprintf(gettext("need Digest::SHA to index %s"), $page)) if $@;
217			return undef;
218		}
219
220		# Note no colon, therefore it's guaranteed to not overlap
221		# with a page with the same name as the hash..
222		return "U".lc(Digest::SHA::sha1_hex($page));
223	}
224	else {
225		return "U:".$page;
226	}
227}
228
229my $db;
230sub xapiandb () {
231	if (! defined $db) {
232		eval q{
233			use Search::Xapian;
234			use Search::Xapian::WritableDatabase;
235		};
236		error($@) if $@;
237		$db=Search::Xapian::WritableDatabase->new($config{wikistatedir}."/xapian/default",
238			Search::Xapian::DB_CREATE_OR_OPEN());
239	}
240	return $db;
241}
242
243{
244my $setup=0;
245sub setupfiles () {
246	if (! $setup and (! -e $config{wikistatedir}."/xapian" || $config{rebuild})) {
247		writefile("omega.conf", $config{wikistatedir}."/xapian",
248			"database_dir .\n".
249			"template_dir ./templates\n");
250		omega_template();
251		$setup=1;
252	}
253}
254}
255
256sub needsbuild {
257	my $list=shift;
258	if (grep {
259		$_ eq "templates/page.tmpl" ||
260		$_ eq "templates/searchquery.tmpl"
261	} @$list) {
262		omega_template();
263	}
264}
265
266sub omega_template {
267	# Avoid omega interpreting anything in the cgitemplate
268	# as an omegascript command.
269	eval q{use IkiWiki::CGI};
270	my $template=IkiWiki::cgitemplate(undef, gettext("search"), "\0",
271		searchform => "", # avoid showing the small search form
272	);
273	eval q{use HTML::Entities};
274	error $@ if $@;
275	$template=encode_entities($template, '\$');
276
277	my $querytemplate=readfile(IkiWiki::template_file("searchquery.tmpl"));
278	$template=~s/\0/$querytemplate/;
279	writefile("query", $config{wikistatedir}."/xapian/templates",
280		$template);
281}
282
283sub disable () {
284	if (-d $config{wikistatedir}."/xapian") {
285		system("rm", "-rf", $config{wikistatedir}."/xapian");
286	}
287}
288
2891
290