diff options
Diffstat (limited to 'inc/fulltext.php')
-rw-r--r-- | inc/fulltext.php | 753 |
1 files changed, 753 insertions, 0 deletions
diff --git a/inc/fulltext.php b/inc/fulltext.php new file mode 100644 index 000000000..620237296 --- /dev/null +++ b/inc/fulltext.php @@ -0,0 +1,753 @@ +<?php +/** + * DokuWiki fulltextsearch functions using the index + * + * @license GPL 2 (http://www.gnu.org/licenses/gpl.html) + * @author Andreas Gohr <andi@splitbrain.org> + */ + +if(!defined('DOKU_INC')) die('meh.'); + +/** + * create snippets for the first few results only + */ +if(!defined('FT_SNIPPET_NUMBER')) define('FT_SNIPPET_NUMBER',15); + +/** + * The fulltext search + * + * Returns a list of matching documents for the given query + * + * refactored into ft_pageSearch(), _ft_pageSearch() and trigger_event() + * + */ +function ft_pageSearch($query,&$highlight){ + + $data['query'] = $query; + $data['highlight'] =& $highlight; + + return trigger_event('SEARCH_QUERY_FULLPAGE', $data, '_ft_pageSearch'); +} + +/** + * Returns a list of matching documents for the given query + * + * @author Andreas Gohr <andi@splitbrain.org> + * @author Kazutaka Miyasaka <kazmiya@gmail.com> + */ +function _ft_pageSearch(&$data) { + $Indexer = idx_get_indexer(); + + // parse the given query + $q = ft_queryParser($Indexer, $data['query']); + $data['highlight'] = $q['highlight']; + + if (empty($q['parsed_ary'])) return array(); + + // lookup all words found in the query + $lookup = $Indexer->lookup($q['words']); + + // get all pages in this dokuwiki site (!: includes nonexistent pages) + $pages_all = array(); + foreach ($Indexer->getPages() as $id) { + $pages_all[$id] = 0; // base: 0 hit + } + + // process the query + $stack = array(); + foreach ($q['parsed_ary'] as $token) { + switch (substr($token, 0, 3)) { + case 'W+:': + case 'W-:': + case 'W_:': // word + $word = substr($token, 3); + $stack[] = (array) $lookup[$word]; + break; + case 'P+:': + case 'P-:': // phrase + $phrase = substr($token, 3); + // since phrases are always parsed as ((W1)(W2)...(P)), + // the end($stack) always points the pages that contain + // all words in this phrase + $pages = end($stack); + $pages_matched = array(); + foreach(array_keys($pages) as $id){ + $text = utf8_strtolower(rawWiki($id)); + if (strpos($text, $phrase) !== false) { + $pages_matched[$id] = 0; // phrase: always 0 hit + } + } + $stack[] = $pages_matched; + break; + case 'N+:': + case 'N-:': // namespace + $ns = substr($token, 3); + $pages_matched = array(); + foreach (array_keys($pages_all) as $id) { + if (strpos($id, $ns) === 0) { + $pages_matched[$id] = 0; // namespace: always 0 hit + } + } + $stack[] = $pages_matched; + break; + case 'AND': // and operation + list($pages1, $pages2) = array_splice($stack, -2); + $stack[] = ft_resultCombine(array($pages1, $pages2)); + break; + case 'OR': // or operation + list($pages1, $pages2) = array_splice($stack, -2); + $stack[] = ft_resultUnite(array($pages1, $pages2)); + break; + case 'NOT': // not operation (unary) + $pages = array_pop($stack); + $stack[] = ft_resultComplement(array($pages_all, $pages)); + break; + } + } + $docs = array_pop($stack); + + if (empty($docs)) return array(); + + // check: settings, acls, existence + foreach (array_keys($docs) as $id) { + if (isHiddenPage($id) || auth_quickaclcheck($id) < AUTH_READ || !page_exists($id, '', false)) { + unset($docs[$id]); + } + } + + // sort docs by count + arsort($docs); + + return $docs; +} + +/** + * Returns the backlinks for a given page + * + * Uses the metadata index. + */ +function ft_backlinks($id){ + $result = array(); + + $result = idx_get_indexer()->lookupKey('relation_references', $id); + + if(!count($result)) return $result; + + // check ACL permissions + foreach(array_keys($result) as $idx){ + if(isHiddenPage($result[$idx]) || auth_quickaclcheck($result[$idx]) < AUTH_READ || !page_exists($result[$idx], '', false)){ + unset($result[$idx]); + } + } + + sort($result); + return $result; +} + +/** + * Returns the pages that use a given media file + * + * Does a quick lookup with the fulltext index, then + * evaluates the instructions of the found pages + * + * Aborts after $max found results + */ +function ft_mediause($id,$max){ + if(!$max) $max = 1; // need to find at least one + + $result = array(); + + // quick lookup of the mediafile + // FIXME use metadata key lookup + $media = noNS($id); + $matches = idx_lookup(idx_tokenizer($media)); + $docs = array_keys(ft_resultCombine(array_values($matches))); + if(!count($docs)) return $result; + + // go through all found pages + $found = 0; + $pcre = preg_quote($media,'/'); + foreach($docs as $doc){ + $ns = getNS($doc); + preg_match_all('/\{\{([^|}]*'.$pcre.'[^|}]*)(|[^}]+)?\}\}/i',rawWiki($doc),$matches); + foreach($matches[1] as $img){ + $img = trim($img); + if(preg_match('/^https?:\/\//i',$img)) continue; // skip external images + list($img) = explode('?',$img); // remove any parameters + resolve_mediaid($ns,$img,$exists); // resolve the possibly relative img + + if($img == $id){ // we have a match + $result[] = $doc; + $found++; + break; + } + } + if($found >= $max) break; + } + + sort($result); + return $result; +} + + + +/** + * Quicksearch for pagenames + * + * By default it only matches the pagename and ignores the + * namespace. This can be changed with the second parameter. + * The third parameter allows to search in titles as well. + * + * The function always returns titles as well + * + * @triggers SEARCH_QUERY_PAGELOOKUP + * @author Andreas Gohr <andi@splitbrain.org> + * @author Adrian Lang <lang@cosmocode.de> + */ +function ft_pageLookup($id, $in_ns=false, $in_title=false){ + $data = compact('id', 'in_ns', 'in_title'); + $data['has_titles'] = true; // for plugin backward compatibility check + return trigger_event('SEARCH_QUERY_PAGELOOKUP', $data, '_ft_pageLookup'); +} + +function _ft_pageLookup(&$data){ + // split out original parameters + $id = $data['id']; + if (preg_match('/(?:^| )@(\w+)/', $id, $matches)) { + $ns = cleanID($matches[1]) . ':'; + $id = str_replace($matches[0], '', $id); + } + + $in_ns = $data['in_ns']; + $in_title = $data['in_title']; + $cleaned = cleanID($id); + + $Indexer = idx_get_indexer(); + $page_idx = $Indexer->getPages(); + + $pages = array(); + if ($id !== '' && $cleaned !== '') { + foreach ($page_idx as $p_id) { + if ((strpos($in_ns ? $p_id : noNSorNS($p_id), $cleaned) !== false)) { + if (!isset($pages[$p_id])) + $pages[$p_id] = p_get_first_heading($p_id, METADATA_DONT_RENDER); + } + } + if ($in_title) { + foreach ($Indexer->lookupKey('title', $id, '_ft_pageLookupTitleCompare') as $p_id) { + if (!isset($pages[$p_id])) + $pages[$p_id] = p_get_first_heading($p_id, METADATA_DONT_RENDER); + } + } + } + + if (isset($ns)) { + foreach (array_keys($pages) as $p_id) { + if (strpos($p_id, $ns) !== 0) { + unset($pages[$p_id]); + } + } + } + + // discard hidden pages + // discard nonexistent pages + // check ACL permissions + foreach(array_keys($pages) as $idx){ + if(!isVisiblePage($idx) || !page_exists($idx) || + auth_quickaclcheck($idx) < AUTH_READ) { + unset($pages[$idx]); + } + } + + uksort($pages,'ft_pagesorter'); + return $pages; +} + +/** + * Tiny helper function for comparing the searched title with the title + * from the search index. This function is a wrapper around stripos with + * adapted argument order and return value. + */ +function _ft_pageLookupTitleCompare($search, $title) { + return stripos($title, $search) !== false; +} + +/** + * Sort pages based on their namespace level first, then on their string + * values. This makes higher hierarchy pages rank higher than lower hierarchy + * pages. + */ +function ft_pagesorter($a, $b){ + $ac = count(explode(':',$a)); + $bc = count(explode(':',$b)); + if($ac < $bc){ + return -1; + }elseif($ac > $bc){ + return 1; + } + return strcmp ($a,$b); +} + +/** + * Creates a snippet extract + * + * @author Andreas Gohr <andi@splitbrain.org> + * @triggers FULLTEXT_SNIPPET_CREATE + */ +function ft_snippet($id,$highlight){ + $text = rawWiki($id); + $text = str_replace("\xC2\xAD",'',$text); // remove soft-hyphens + $evdata = array( + 'id' => $id, + 'text' => &$text, + 'highlight' => &$highlight, + 'snippet' => '', + ); + + $evt = new Doku_Event('FULLTEXT_SNIPPET_CREATE',$evdata); + if ($evt->advise_before()) { + $match = array(); + $snippets = array(); + $utf8_offset = $offset = $end = 0; + $len = utf8_strlen($text); + + // build a regexp from the phrases to highlight + $re1 = '('.join('|',array_map('ft_snippet_re_preprocess', array_map('preg_quote_cb',array_filter((array) $highlight)))).')'; + $re2 = "$re1.{0,75}(?!\\1)$re1"; + $re3 = "$re1.{0,45}(?!\\1)$re1.{0,45}(?!\\1)(?!\\2)$re1"; + + for ($cnt=4; $cnt--;) { + if (0) { + } else if (preg_match('/'.$re3.'/iu',$text,$match,PREG_OFFSET_CAPTURE,$offset)) { + } else if (preg_match('/'.$re2.'/iu',$text,$match,PREG_OFFSET_CAPTURE,$offset)) { + } else if (preg_match('/'.$re1.'/iu',$text,$match,PREG_OFFSET_CAPTURE,$offset)) { + } else { + break; + } + + list($str,$idx) = $match[0]; + + // convert $idx (a byte offset) into a utf8 character offset + $utf8_idx = utf8_strlen(substr($text,0,$idx)); + $utf8_len = utf8_strlen($str); + + // establish context, 100 bytes surrounding the match string + // first look to see if we can go 100 either side, + // then drop to 50 adding any excess if the other side can't go to 50, + $pre = min($utf8_idx-$utf8_offset,100); + $post = min($len-$utf8_idx-$utf8_len,100); + + if ($pre>50 && $post>50) { + $pre = $post = 50; + } else if ($pre>50) { + $pre = min($pre,100-$post); + } else if ($post>50) { + $post = min($post, 100-$pre); + } else { + // both are less than 50, means the context is the whole string + // make it so and break out of this loop - there is no need for the + // complex snippet calculations + $snippets = array($text); + break; + } + + // establish context start and end points, try to append to previous + // context if possible + $start = $utf8_idx - $pre; + $append = ($start < $end) ? $end : false; // still the end of the previous context snippet + $end = $utf8_idx + $utf8_len + $post; // now set it to the end of this context + + if ($append) { + $snippets[count($snippets)-1] .= utf8_substr($text,$append,$end-$append); + } else { + $snippets[] = utf8_substr($text,$start,$end-$start); + } + + // set $offset for next match attempt + // substract strlen to avoid splitting a potential search success, + // this is an approximation as the search pattern may match strings + // of varying length and it will fail if the context snippet + // boundary breaks a matching string longer than the current match + $utf8_offset = $utf8_idx + $post; + $offset = $idx + strlen(utf8_substr($text,$utf8_idx,$post)); + $offset = utf8_correctIdx($text,$offset); + } + + $m = "\1"; + $snippets = preg_replace('/'.$re1.'/iu',$m.'$1'.$m,$snippets); + $snippet = preg_replace('/'.$m.'([^'.$m.']*?)'.$m.'/iu','<strong class="search_hit">$1</strong>',hsc(join('... ',$snippets))); + + $evdata['snippet'] = $snippet; + } + $evt->advise_after(); + unset($evt); + + return $evdata['snippet']; +} + +/** + * Wraps a search term in regex boundary checks. + */ +function ft_snippet_re_preprocess($term) { + // do not process asian terms where word boundaries are not explicit + if(preg_match('/'.IDX_ASIAN.'/u',$term)){ + return $term; + } + + if(substr($term,0,2) == '\\*'){ + $term = substr($term,2); + }else{ + $term = '\b'.$term; + } + + if(substr($term,-2,2) == '\\*'){ + $term = substr($term,0,-2); + }else{ + $term = $term.'\b'; + } + return $term; +} + +/** + * Combine found documents and sum up their scores + * + * This function is used to combine searched words with a logical + * AND. Only documents available in all arrays are returned. + * + * based upon PEAR's PHP_Compat function for array_intersect_key() + * + * @param array $args An array of page arrays + */ +function ft_resultCombine($args){ + $array_count = count($args); + if($array_count == 1){ + return $args[0]; + } + + $result = array(); + if ($array_count > 1) { + foreach ($args[0] as $key => $value) { + $result[$key] = $value; + for ($i = 1; $i !== $array_count; $i++) { + if (!isset($args[$i][$key])) { + unset($result[$key]); + break; + } + $result[$key] += $args[$i][$key]; + } + } + } + return $result; +} + +/** + * Unites found documents and sum up their scores + * + * based upon ft_resultCombine() function + * + * @param array $args An array of page arrays + * @author Kazutaka Miyasaka <kazmiya@gmail.com> + */ +function ft_resultUnite($args) { + $array_count = count($args); + if ($array_count === 1) { + return $args[0]; + } + + $result = $args[0]; + for ($i = 1; $i !== $array_count; $i++) { + foreach (array_keys($args[$i]) as $id) { + $result[$id] += $args[$i][$id]; + } + } + return $result; +} + +/** + * Computes the difference of documents using page id for comparison + * + * nearly identical to PHP5's array_diff_key() + * + * @param array $args An array of page arrays + * @author Kazutaka Miyasaka <kazmiya@gmail.com> + */ +function ft_resultComplement($args) { + $array_count = count($args); + if ($array_count === 1) { + return $args[0]; + } + + $result = $args[0]; + foreach (array_keys($result) as $id) { + for ($i = 1; $i !== $array_count; $i++) { + if (isset($args[$i][$id])) unset($result[$id]); + } + } + return $result; +} + +/** + * Parses a search query and builds an array of search formulas + * + * @author Andreas Gohr <andi@splitbrain.org> + * @author Kazutaka Miyasaka <kazmiya@gmail.com> + */ +function ft_queryParser($Indexer, $query){ + /** + * parse a search query and transform it into intermediate representation + * + * in a search query, you can use the following expressions: + * + * words: + * include + * -exclude + * phrases: + * "phrase to be included" + * -"phrase you want to exclude" + * namespaces: + * @include:namespace (or ns:include:namespace) + * ^exclude:namespace (or -ns:exclude:namespace) + * groups: + * () + * -() + * operators: + * and ('and' is the default operator: you can always omit this) + * or (or pipe symbol '|', lower precedence than 'and') + * + * e.g. a query [ aa "bb cc" @dd:ee ] means "search pages which contain + * a word 'aa', a phrase 'bb cc' and are within a namespace 'dd:ee'". + * this query is equivalent to [ -(-aa or -"bb cc" or -ns:dd:ee) ] + * as long as you don't mind hit counts. + * + * intermediate representation consists of the following parts: + * + * ( ) - group + * AND - logical and + * OR - logical or + * NOT - logical not + * W+:, W-:, W_: - word (underscore: no need to highlight) + * P+:, P-: - phrase (minus sign: logically in NOT group) + * N+:, N-: - namespace + */ + $parsed_query = ''; + $parens_level = 0; + $terms = preg_split('/(-?".*?")/u', utf8_strtolower($query), -1, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY); + + foreach ($terms as $term) { + $parsed = ''; + if (preg_match('/^(-?)"(.+)"$/u', $term, $matches)) { + // phrase-include and phrase-exclude + $not = $matches[1] ? 'NOT' : ''; + $parsed = $not.ft_termParser($Indexer, $matches[2], false, true); + } else { + // fix incomplete phrase + $term = str_replace('"', ' ', $term); + + // fix parentheses + $term = str_replace(')' , ' ) ', $term); + $term = str_replace('(' , ' ( ', $term); + $term = str_replace('- (', ' -(', $term); + + // treat pipe symbols as 'OR' operators + $term = str_replace('|', ' or ', $term); + + // treat ideographic spaces (U+3000) as search term separators + // FIXME: some more separators? + $term = preg_replace('/[ \x{3000}]+/u', ' ', $term); + $term = trim($term); + if ($term === '') continue; + + $tokens = explode(' ', $term); + foreach ($tokens as $token) { + if ($token === '(') { + // parenthesis-include-open + $parsed .= '('; + ++$parens_level; + } elseif ($token === '-(') { + // parenthesis-exclude-open + $parsed .= 'NOT('; + ++$parens_level; + } elseif ($token === ')') { + // parenthesis-any-close + if ($parens_level === 0) continue; + $parsed .= ')'; + $parens_level--; + } elseif ($token === 'and') { + // logical-and (do nothing) + } elseif ($token === 'or') { + // logical-or + $parsed .= 'OR'; + } elseif (preg_match('/^(?:\^|-ns:)(.+)$/u', $token, $matches)) { + // namespace-exclude + $parsed .= 'NOT(N+:'.$matches[1].')'; + } elseif (preg_match('/^(?:@|ns:)(.+)$/u', $token, $matches)) { + // namespace-include + $parsed .= '(N+:'.$matches[1].')'; + } elseif (preg_match('/^-(.+)$/', $token, $matches)) { + // word-exclude + $parsed .= 'NOT('.ft_termParser($Indexer, $matches[1]).')'; + } else { + // word-include + $parsed .= ft_termParser($Indexer, $token); + } + } + } + $parsed_query .= $parsed; + } + + // cleanup (very sensitive) + $parsed_query .= str_repeat(')', $parens_level); + do { + $parsed_query_old = $parsed_query; + $parsed_query = preg_replace('/(NOT)?\(\)/u', '', $parsed_query); + } while ($parsed_query !== $parsed_query_old); + $parsed_query = preg_replace('/(NOT|OR)+\)/u', ')' , $parsed_query); + $parsed_query = preg_replace('/(OR)+/u' , 'OR' , $parsed_query); + $parsed_query = preg_replace('/\(OR/u' , '(' , $parsed_query); + $parsed_query = preg_replace('/^OR|OR$/u' , '' , $parsed_query); + $parsed_query = preg_replace('/\)(NOT)?\(/u' , ')AND$1(', $parsed_query); + + // adjustment: make highlightings right + $parens_level = 0; + $notgrp_levels = array(); + $parsed_query_new = ''; + $tokens = preg_split('/(NOT\(|[()])/u', $parsed_query, -1, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY); + foreach ($tokens as $token) { + if ($token === 'NOT(') { + $notgrp_levels[] = ++$parens_level; + } elseif ($token === '(') { + ++$parens_level; + } elseif ($token === ')') { + if ($parens_level-- === end($notgrp_levels)) array_pop($notgrp_levels); + } elseif (count($notgrp_levels) % 2 === 1) { + // turn highlight-flag off if terms are logically in "NOT" group + $token = preg_replace('/([WPN])\+\:/u', '$1-:', $token); + } + $parsed_query_new .= $token; + } + $parsed_query = $parsed_query_new; + + /** + * convert infix notation string into postfix (Reverse Polish notation) array + * by Shunting-yard algorithm + * + * see: http://en.wikipedia.org/wiki/Reverse_Polish_notation + * see: http://en.wikipedia.org/wiki/Shunting-yard_algorithm + */ + $parsed_ary = array(); + $ope_stack = array(); + $ope_precedence = array(')' => 1, 'OR' => 2, 'AND' => 3, 'NOT' => 4, '(' => 5); + $ope_regex = '/([()]|OR|AND|NOT)/u'; + + $tokens = preg_split($ope_regex, $parsed_query, -1, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY); + foreach ($tokens as $token) { + if (preg_match($ope_regex, $token)) { + // operator + $last_ope = end($ope_stack); + while ($ope_precedence[$token] <= $ope_precedence[$last_ope] && $last_ope != '(') { + $parsed_ary[] = array_pop($ope_stack); + $last_ope = end($ope_stack); + } + if ($token == ')') { + array_pop($ope_stack); // this array_pop always deletes '(' + } else { + $ope_stack[] = $token; + } + } else { + // operand + $token_decoded = str_replace(array('OP', 'CP'), array('(', ')'), $token); + $parsed_ary[] = $token_decoded; + } + } + $parsed_ary = array_values(array_merge($parsed_ary, array_reverse($ope_stack))); + + // cleanup: each double "NOT" in RPN array actually does nothing + $parsed_ary_count = count($parsed_ary); + for ($i = 1; $i < $parsed_ary_count; ++$i) { + if ($parsed_ary[$i] === 'NOT' && $parsed_ary[$i - 1] === 'NOT') { + unset($parsed_ary[$i], $parsed_ary[$i - 1]); + } + } + $parsed_ary = array_values($parsed_ary); + + // build return value + $q = array(); + $q['query'] = $query; + $q['parsed_str'] = $parsed_query; + $q['parsed_ary'] = $parsed_ary; + + foreach ($q['parsed_ary'] as $token) { + if ($token[2] !== ':') continue; + $body = substr($token, 3); + + switch (substr($token, 0, 3)) { + case 'N+:': + $q['ns'][] = $body; // for backward compatibility + break; + case 'N-:': + $q['notns'][] = $body; // for backward compatibility + break; + case 'W_:': + $q['words'][] = $body; + break; + case 'W-:': + $q['words'][] = $body; + $q['not'][] = $body; // for backward compatibility + break; + case 'W+:': + $q['words'][] = $body; + $q['highlight'][] = $body; + $q['and'][] = $body; // for backward compatibility + break; + case 'P-:': + $q['phrases'][] = $body; + break; + case 'P+:': + $q['phrases'][] = $body; + $q['highlight'][] = $body; + break; + } + } + foreach (array('words', 'phrases', 'highlight', 'ns', 'notns', 'and', 'not') as $key) { + $q[$key] = empty($q[$key]) ? array() : array_values(array_unique($q[$key])); + } + + return $q; +} + +/** + * Transforms given search term into intermediate representation + * + * This function is used in ft_queryParser() and not for general purpose use. + * + * @author Kazutaka Miyasaka <kazmiya@gmail.com> + */ +function ft_termParser($Indexer, $term, $consider_asian = true, $phrase_mode = false) { + $parsed = ''; + if ($consider_asian) { + // successive asian characters need to be searched as a phrase + $words = preg_split('/('.IDX_ASIAN.'+)/u', $term, -1, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY); + foreach ($words as $word) { + $phrase_mode = $phrase_mode ? true : preg_match('/'.IDX_ASIAN.'/u', $word); + $parsed .= ft_termParser($Indexer, $word, false, $phrase_mode); + } + } else { + $term_noparen = str_replace(array('(', ')'), ' ', $term); + $words = $Indexer->tokenizer($term_noparen, true); + + // W_: no need to highlight + if (empty($words)) { + $parsed = '()'; // important: do not remove + } elseif ($words[0] === $term) { + $parsed = '(W+:'.$words[0].')'; + } elseif ($phrase_mode) { + $term_encoded = str_replace(array('(', ')'), array('OP', 'CP'), $term); + $parsed = '((W_:'.implode(')(W_:', $words).')(P+:'.$term_encoded.'))'; + } else { + $parsed = '((W+:'.implode(')(W+:', $words).'))'; + } + } + return $parsed; +} + +//Setup VIM: ex: et ts=4 : |