Mercurial > defr > drupal > core
diff modules/search/search.module @ 1:c1f4ac30525a 6.0
Drupal 6.0
| author | Franck Deroche <webmaster@defr.org> |
|---|---|
| date | Tue, 23 Dec 2008 14:28:28 +0100 |
| parents | |
| children | 2427550111ae |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/modules/search/search.module Tue Dec 23 14:28:28 2008 +0100 @@ -0,0 +1,1290 @@ +<?php +// $Id: search.module,v 1.250.2.1 2008/02/07 16:42:03 goba Exp $ + +/** + * @file + * Enables site-wide keyword searching. + */ + +/** + * Matches Unicode character classes to exclude from the search index. + * + * See: http://www.unicode.org/Public/UNIDATA/UCD.html#General_Category_Values + * + * The index only contains the following character classes: + * Lu Letter, Uppercase + * Ll Letter, Lowercase + * Lt Letter, Titlecase + * Lo Letter, Other + * Nd Number, Decimal Digit + * No Number, Other + */ +define('PREG_CLASS_SEARCH_EXCLUDE', +'\x{0}-\x{2f}\x{3a}-\x{40}\x{5b}-\x{60}\x{7b}-\x{bf}\x{d7}\x{f7}\x{2b0}-'. +'\x{385}\x{387}\x{3f6}\x{482}-\x{489}\x{559}-\x{55f}\x{589}-\x{5c7}\x{5f3}-'. +'\x{61f}\x{640}\x{64b}-\x{65e}\x{66a}-\x{66d}\x{670}\x{6d4}\x{6d6}-\x{6ed}'. +'\x{6fd}\x{6fe}\x{700}-\x{70f}\x{711}\x{730}-\x{74a}\x{7a6}-\x{7b0}\x{901}-'. +'\x{903}\x{93c}\x{93e}-\x{94d}\x{951}-\x{954}\x{962}-\x{965}\x{970}\x{981}-'. +'\x{983}\x{9bc}\x{9be}-\x{9cd}\x{9d7}\x{9e2}\x{9e3}\x{9f2}-\x{a03}\x{a3c}-'. +'\x{a4d}\x{a70}\x{a71}\x{a81}-\x{a83}\x{abc}\x{abe}-\x{acd}\x{ae2}\x{ae3}'. +'\x{af1}-\x{b03}\x{b3c}\x{b3e}-\x{b57}\x{b70}\x{b82}\x{bbe}-\x{bd7}\x{bf0}-'. +'\x{c03}\x{c3e}-\x{c56}\x{c82}\x{c83}\x{cbc}\x{cbe}-\x{cd6}\x{d02}\x{d03}'. +'\x{d3e}-\x{d57}\x{d82}\x{d83}\x{dca}-\x{df4}\x{e31}\x{e34}-\x{e3f}\x{e46}-'. +'\x{e4f}\x{e5a}\x{e5b}\x{eb1}\x{eb4}-\x{ebc}\x{ec6}-\x{ecd}\x{f01}-\x{f1f}'. +'\x{f2a}-\x{f3f}\x{f71}-\x{f87}\x{f90}-\x{fd1}\x{102c}-\x{1039}\x{104a}-'. +'\x{104f}\x{1056}-\x{1059}\x{10fb}\x{10fc}\x{135f}-\x{137c}\x{1390}-\x{1399}'. +'\x{166d}\x{166e}\x{1680}\x{169b}\x{169c}\x{16eb}-\x{16f0}\x{1712}-\x{1714}'. +'\x{1732}-\x{1736}\x{1752}\x{1753}\x{1772}\x{1773}\x{17b4}-\x{17db}\x{17dd}'. +'\x{17f0}-\x{180e}\x{1843}\x{18a9}\x{1920}-\x{1945}\x{19b0}-\x{19c0}\x{19c8}'. +'\x{19c9}\x{19de}-\x{19ff}\x{1a17}-\x{1a1f}\x{1d2c}-\x{1d61}\x{1d78}\x{1d9b}-'. +'\x{1dc3}\x{1fbd}\x{1fbf}-\x{1fc1}\x{1fcd}-\x{1fcf}\x{1fdd}-\x{1fdf}\x{1fed}-'. +'\x{1fef}\x{1ffd}-\x{2070}\x{2074}-\x{207e}\x{2080}-\x{2101}\x{2103}-\x{2106}'. +'\x{2108}\x{2109}\x{2114}\x{2116}-\x{2118}\x{211e}-\x{2123}\x{2125}\x{2127}'. +'\x{2129}\x{212e}\x{2132}\x{213a}\x{213b}\x{2140}-\x{2144}\x{214a}-\x{2b13}'. +'\x{2ce5}-\x{2cff}\x{2d6f}\x{2e00}-\x{3005}\x{3007}-\x{303b}\x{303d}-\x{303f}'. +'\x{3099}-\x{309e}\x{30a0}\x{30fb}-\x{30fe}\x{3190}-\x{319f}\x{31c0}-\x{31cf}'. +'\x{3200}-\x{33ff}\x{4dc0}-\x{4dff}\x{a015}\x{a490}-\x{a716}\x{a802}\x{a806}'. +'\x{a80b}\x{a823}-\x{a82b}\x{d800}-\x{f8ff}\x{fb1e}\x{fb29}\x{fd3e}\x{fd3f}'. +'\x{fdfc}-\x{fe6b}\x{feff}-\x{ff0f}\x{ff1a}-\x{ff20}\x{ff3b}-\x{ff40}\x{ff5b}-'. +'\x{ff65}\x{ff70}\x{ff9e}\x{ff9f}\x{ffe0}-\x{fffd}'); + +/** + * Matches all 'N' Unicode character classes (numbers) + */ +define('PREG_CLASS_NUMBERS', +'\x{30}-\x{39}\x{b2}\x{b3}\x{b9}\x{bc}-\x{be}\x{660}-\x{669}\x{6f0}-\x{6f9}'. +'\x{966}-\x{96f}\x{9e6}-\x{9ef}\x{9f4}-\x{9f9}\x{a66}-\x{a6f}\x{ae6}-\x{aef}'. +'\x{b66}-\x{b6f}\x{be7}-\x{bf2}\x{c66}-\x{c6f}\x{ce6}-\x{cef}\x{d66}-\x{d6f}'. +'\x{e50}-\x{e59}\x{ed0}-\x{ed9}\x{f20}-\x{f33}\x{1040}-\x{1049}\x{1369}-'. +'\x{137c}\x{16ee}-\x{16f0}\x{17e0}-\x{17e9}\x{17f0}-\x{17f9}\x{1810}-\x{1819}'. +'\x{1946}-\x{194f}\x{2070}\x{2074}-\x{2079}\x{2080}-\x{2089}\x{2153}-\x{2183}'. +'\x{2460}-\x{249b}\x{24ea}-\x{24ff}\x{2776}-\x{2793}\x{3007}\x{3021}-\x{3029}'. +'\x{3038}-\x{303a}\x{3192}-\x{3195}\x{3220}-\x{3229}\x{3251}-\x{325f}\x{3280}-'. +'\x{3289}\x{32b1}-\x{32bf}\x{ff10}-\x{ff19}'); + +/** + * Matches all 'P' Unicode character classes (punctuation) + */ +define('PREG_CLASS_PUNCTUATION', +'\x{21}-\x{23}\x{25}-\x{2a}\x{2c}-\x{2f}\x{3a}\x{3b}\x{3f}\x{40}\x{5b}-\x{5d}'. +'\x{5f}\x{7b}\x{7d}\x{a1}\x{ab}\x{b7}\x{bb}\x{bf}\x{37e}\x{387}\x{55a}-\x{55f}'. +'\x{589}\x{58a}\x{5be}\x{5c0}\x{5c3}\x{5f3}\x{5f4}\x{60c}\x{60d}\x{61b}\x{61f}'. +'\x{66a}-\x{66d}\x{6d4}\x{700}-\x{70d}\x{964}\x{965}\x{970}\x{df4}\x{e4f}'. +'\x{e5a}\x{e5b}\x{f04}-\x{f12}\x{f3a}-\x{f3d}\x{f85}\x{104a}-\x{104f}\x{10fb}'. +'\x{1361}-\x{1368}\x{166d}\x{166e}\x{169b}\x{169c}\x{16eb}-\x{16ed}\x{1735}'. +'\x{1736}\x{17d4}-\x{17d6}\x{17d8}-\x{17da}\x{1800}-\x{180a}\x{1944}\x{1945}'. +'\x{2010}-\x{2027}\x{2030}-\x{2043}\x{2045}-\x{2051}\x{2053}\x{2054}\x{2057}'. +'\x{207d}\x{207e}\x{208d}\x{208e}\x{2329}\x{232a}\x{23b4}-\x{23b6}\x{2768}-'. +'\x{2775}\x{27e6}-\x{27eb}\x{2983}-\x{2998}\x{29d8}-\x{29db}\x{29fc}\x{29fd}'. +'\x{3001}-\x{3003}\x{3008}-\x{3011}\x{3014}-\x{301f}\x{3030}\x{303d}\x{30a0}'. +'\x{30fb}\x{fd3e}\x{fd3f}\x{fe30}-\x{fe52}\x{fe54}-\x{fe61}\x{fe63}\x{fe68}'. +'\x{fe6a}\x{fe6b}\x{ff01}-\x{ff03}\x{ff05}-\x{ff0a}\x{ff0c}-\x{ff0f}\x{ff1a}'. +'\x{ff1b}\x{ff1f}\x{ff20}\x{ff3b}-\x{ff3d}\x{ff3f}\x{ff5b}\x{ff5d}\x{ff5f}-'. +'\x{ff65}'); + +/** + * Matches all CJK characters that are candidates for auto-splitting + * (Chinese, Japanese, Korean). + * Contains kana and BMP ideographs. + */ +define('PREG_CLASS_CJK', '\x{3041}-\x{30ff}\x{31f0}-\x{31ff}\x{3400}-\x{4db5}'. +'\x{4e00}-\x{9fbb}\x{f900}-\x{fad9}'); + +/** + * Implementation of hook_help(). + */ +function search_help($path, $arg) { + switch ($path) { + case 'admin/help#search': + $output = '<p>'. t('The search module adds the ability to search for content by keywords. Search is often the only practical way to find content on a large site, and is useful for finding both users and posts.') .'</p>'; + $output .= '<p>'. t('To provide keyword searching, the search engine maintains an index of words found in your site\'s content. To build and maintain this index, a correctly configured <a href="@cron">cron maintenance task</a> is required. Indexing behavior can be adjusted using the <a href="@searchsettings">search settings page</a>; for example, the <em>Number of items to index per cron run</em> sets the maximum number of items indexed in each pass of a <a href="@cron">cron maintenance task</a>. If necessary, reduce this number to prevent timeouts and memory errors when indexing.', array('@cron' => url('admin/reports/status'), '@searchsettings' => url('admin/settings/search'))) .'</p>'; + $output .= '<p>'. t('For more information, see the online handbook entry for <a href="@search">Search module</a>.', array('@search' => 'http://drupal.org/handbook/modules/search/')) .'</p>'; + return $output; + case 'admin/settings/search': + return '<p>'. t('The search engine maintains an index of words found in your site\'s content. To build and maintain this index, a correctly configured <a href="@cron">cron maintenance task</a> is required. Indexing behavior can be adjusted using the settings below.', array('@cron' => url('admin/reports/status'))) .'</p>'; + case 'search#noresults': + return t('<ul> +<li>Check if your spelling is correct.</li> +<li>Remove quotes around phrases to match each word individually: <em>"blue smurf"</em> will match less than <em>blue smurf</em>.</li> +<li>Consider loosening your query with <em>OR</em>: <em>blue smurf</em> will match less than <em>blue OR smurf</em>.</li> +</ul>'); + } +} + +/** + * Implementation of hook_theme() + */ +function search_theme() { + return array( + 'search_theme_form' => array( + 'arguments' => array('form' => NULL), + 'template' => 'search-theme-form', + ), + 'search_block_form' => array( + 'arguments' => array('form' => NULL), + 'template' => 'search-block-form', + ), + 'search_result' => array( + 'arguments' => array('result' => NULL, 'type' => NULL), + 'file' => 'search.pages.inc', + 'template' => 'search-result', + ), + 'search_results' => array( + 'arguments' => array('results' => NULL, 'type' => NULL), + 'file' => 'search.pages.inc', + 'template' => 'search-results', + ), + ); +} + +/** + * Implementation of hook_perm(). + */ +function search_perm() { + return array('search content', 'use advanced search', 'administer search'); +} + +/** + * Implementation of hook_block(). + */ +function search_block($op = 'list', $delta = 0) { + if ($op == 'list') { + $blocks[0]['info'] = t('Search form'); + // Not worth caching. + $blocks[0]['cache'] = BLOCK_NO_CACHE; + return $blocks; + } + else if ($op == 'view' && user_access('search content')) { + $block['content'] = drupal_get_form('search_block_form'); + $block['subject'] = t('Search'); + return $block; + } +} + +/** + * Implementation of hook_menu(). + */ +function search_menu() { + $items['search'] = array( + 'title' => 'Search', + 'page callback' => 'search_view', + 'access arguments' => array('search content'), + 'type' => MENU_SUGGESTED_ITEM, + 'file' => 'search.pages.inc', + ); + $items['admin/settings/search'] = array( + 'title' => 'Search settings', + 'description' => 'Configure relevance settings for search and other indexing options', + 'page callback' => 'drupal_get_form', + 'page arguments' => array('search_admin_settings'), + 'access arguments' => array('administer search'), + 'type' => MENU_NORMAL_ITEM, + 'file' => 'search.admin.inc', + ); + $items['admin/settings/search/wipe'] = array( + 'title' => 'Clear index', + 'page callback' => 'drupal_get_form', + 'page arguments' => array('search_wipe_confirm'), + 'access arguments' => array('administer search'), + 'type' => MENU_CALLBACK, + 'file' => 'search.admin.inc', + ); + $items['admin/reports/search'] = array( + 'title' => 'Top search phrases', + 'description' => 'View most popular search phrases.', + 'page callback' => 'dblog_top', + 'page arguments' => array('search'), + 'file' => 'dblog.admin.inc', + 'file path' => drupal_get_path('module', 'dblog'), + ); + + foreach (module_implements('search') as $name) { + $items['search/'. $name .'/%menu_tail'] = array( + 'title callback' => 'module_invoke', + 'title arguments' => array($name, 'search', 'name', TRUE), + 'page callback' => 'search_view', + 'page arguments' => array($name), + 'access callback' => '_search_menu', + 'access arguments' => array($name), + 'type' => MENU_LOCAL_TASK, + 'parent' => 'search', + 'file' => 'search.pages.inc', + ); + } + return $items; +} + +function _search_menu($name) { + return user_access('search content') && module_invoke($name, 'search', 'name'); +} + +/** + * Wipes a part of or the entire search index. + * + * @param $sid + * (optional) The SID of the item to wipe. If specified, $type must be passed + * too. + * @param $type + * (optional) The type of item to wipe. + */ +function search_wipe($sid = NULL, $type = NULL, $reindex = FALSE) { + if ($type == NULL && $sid == NULL) { + module_invoke_all('search', 'reset'); + } + else { + db_query("DELETE FROM {search_dataset} WHERE sid = %d AND type = '%s'", $sid, $type); + db_query("DELETE FROM {search_index} WHERE sid = %d AND type = '%s'", $sid, $type); + // Don't remove links if re-indexing. + if (!$reindex) { + db_query("DELETE FROM {search_node_links} WHERE sid = %d AND type = '%s'", $sid, $type); + } + } +} + +/** + * Marks a word as dirty (or retrieves the list of dirty words). This is used + * during indexing (cron). Words which are dirty have outdated total counts in + * the search_total table, and need to be recounted. + */ +function search_dirty($word = NULL) { + static $dirty = array(); + if ($word !== NULL) { + $dirty[$word] = TRUE; + } + else { + return $dirty; + } +} + +/** + * Implementation of hook_cron(). + * + * Fires hook_update_index() in all modules and cleans up dirty words (see + * search_dirty). + */ +function search_cron() { + // We register a shutdown function to ensure that search_total is always up + // to date. + register_shutdown_function('search_update_totals'); + + // Update word index + foreach (module_list() as $module) { + module_invoke($module, 'update_index'); + } +} + +/** + * This function is called on shutdown to ensure that search_total is always + * up to date (even if cron times out or otherwise fails). + */ +function search_update_totals() { + // Update word IDF (Inverse Document Frequency) counts for new/changed words + foreach (search_dirty() as $word => $dummy) { + // Get total count + $total = db_result(db_query("SELECT SUM(score) FROM {search_index} WHERE word = '%s'", $word)); + // Apply Zipf's law to equalize the probability distribution + $total = log10(1 + 1/(max(1, $total))); + db_query("UPDATE {search_total} SET count = %f WHERE word = '%s'", $total, $word); + if (!db_affected_rows()) { + db_query("INSERT INTO {search_total} (word, count) VALUES ('%s', %f)", $word, $total); + } + } + // Find words that were deleted from search_index, but are still in + // search_total. We use a LEFT JOIN between the two tables and keep only the + // rows which fail to join. + $result = db_query("SELECT t.word AS realword, i.word FROM {search_total} t LEFT JOIN {search_index} i ON t.word = i.word WHERE i.word IS NULL"); + while ($word = db_fetch_object($result)) { + db_query("DELETE FROM {search_total} WHERE word = '%s'", $word->realword); + } +} + +/** + * Simplifies a string according to indexing rules. + */ +function search_simplify($text) { + // Decode entities to UTF-8 + $text = decode_entities($text); + + // Lowercase + $text = drupal_strtolower($text); + + // Call an external processor for word handling. + search_invoke_preprocess($text); + + // Simple CJK handling + if (variable_get('overlap_cjk', TRUE)) { + $text = preg_replace_callback('/['. PREG_CLASS_CJK .']+/u', 'search_expand_cjk', $text); + } + + // To improve searching for numerical data such as dates, IP addresses + // or version numbers, we consider a group of numerical characters + // separated only by punctuation characters to be one piece. + // This also means that searching for e.g. '20/03/1984' also returns + // results with '20-03-1984' in them. + // Readable regexp: ([number]+)[punctuation]+(?=[number]) + $text = preg_replace('/(['. PREG_CLASS_NUMBERS .']+)['. PREG_CLASS_PUNCTUATION .']+(?=['. PREG_CLASS_NUMBERS .'])/u', '\1', $text); + + // The dot, underscore and dash are simply removed. This allows meaningful + // search behavior with acronyms and URLs. + $text = preg_replace('/[._-]+/', '', $text); + + // With the exception of the rules above, we consider all punctuation, + // marks, spacers, etc, to be a word boundary. + $text = preg_replace('/['. PREG_CLASS_SEARCH_EXCLUDE .']+/u', ' ', $text); + + return $text; +} + +/** + * Basic CJK tokenizer. Simply splits a string into consecutive, overlapping + * sequences of characters ('minimum_word_size' long). + */ +function search_expand_cjk($matches) { + $min = variable_get('minimum_word_size', 3); + $str = $matches[0]; + $l = drupal_strlen($str); + // Passthrough short words + if ($l <= $min) { + return ' '. $str .' '; + } + $tokens = ' '; + // FIFO queue of characters + $chars = array(); + // Begin loop + for ($i = 0; $i < $l; ++$i) { + // Grab next character + $current = drupal_substr($str, 0, 1); + $str = substr($str, strlen($current)); + $chars[] = $current; + if ($i >= $min - 1) { + $tokens .= implode('', $chars) .' '; + array_shift($chars); + } + } + return $tokens; +} + +/** + * Splits a string into tokens for indexing. + */ +function search_index_split($text) { + static $last = NULL; + static $lastsplit = NULL; + + if ($last == $text) { + return $lastsplit; + } + // Process words + $text = search_simplify($text); + $words = explode(' ', $text); + array_walk($words, '_search_index_truncate'); + + // Save last keyword result + $last = $text; + $lastsplit = $words; + + return $words; +} + +/** + * Helper function for array_walk in search_index_split. + */ +function _search_index_truncate(&$text) { + $text = truncate_utf8($text, 50); +} + +/** + * Invokes hook_search_preprocess() in modules. + */ +function search_invoke_preprocess(&$text) { + foreach (module_implements('search_preprocess') as $module) { + $text = module_invoke($module, 'search_preprocess', $text); + } +} + +/** + * Update the full-text search index for a particular item. + * + * @param $sid + * A number identifying this particular item (e.g. node id). + * + * @param $type + * A string defining this type of item (e.g. 'node') + * + * @param $text + * The content of this item. Must be a piece of HTML text. + * + * @ingroup search + */ +function search_index($sid, $type, $text) { + $minimum_word_size = variable_get('minimum_word_size', 3); + + // Link matching + global $base_url; + $node_regexp = '@href=[\'"]?(?:'. preg_quote($base_url, '@') .'/|'. preg_quote(base_path(), '@') .')(?:\?q=)?/?((?![a-z]+:)[^\'">]+)[\'">]@i'; + + // Multipliers for scores of words inside certain HTML tags. + // Note: 'a' must be included for link ranking to work. + $tags = array('h1' => 25, + 'h2' => 18, + 'h3' => 15, + 'h4' => 12, + 'h5' => 9, + 'h6' => 6, + 'u' => 3, + 'b' => 3, + 'i' => 3, + 'strong' => 3, + 'em' => 3, + 'a' => 10); + + // Strip off all ignored tags to speed up processing, but insert space before/after + // them to keep word boundaries. + $text = str_replace(array('<', '>'), array(' <', '> '), $text); + $text = strip_tags($text, '<'. implode('><', array_keys($tags)) .'>'); + + // Split HTML tags from plain text. + $split = preg_split('/\s*<([^>]+?)>\s*/', $text, -1, PREG_SPLIT_DELIM_CAPTURE); + // Note: PHP ensures the array consists of alternating delimiters and literals + // and begins and ends with a literal (inserting $null as required). + + $tag = FALSE; // Odd/even counter. Tag or no tag. + $link = FALSE; // State variable for link analyser + $score = 1; // Starting score per word + $accum = ' '; // Accumulator for cleaned up data + $tagstack = array(); // Stack with open tags + $tagwords = 0; // Counter for consecutive words + $focus = 1; // Focus state + + $results = array(0 => array()); // Accumulator for words for index + + foreach ($split as $value) { + if ($tag) { + // Increase or decrease score per word based on tag + list($tagname) = explode(' ', $value, 2); + $tagname = drupal_strtolower($tagname); + // Closing or opening tag? + if ($tagname[0] == '/') { + $tagname = substr($tagname, 1); + // If we encounter unexpected tags, reset score to avoid incorrect boosting. + if (!count($tagstack) || $tagstack[0] != $tagname) { + $tagstack = array(); + $score = 1; + } + else { + // Remove from tag stack and decrement score + $score = max(1, $score - $tags[array_shift($tagstack)]); + } + if ($tagname == 'a') { + $link = FALSE; + } + } + else { + if (isset($tagstack[0]) && $tagstack[0] == $tagname) { + // None of the tags we look for make sense when nested identically. + // If they are, it's probably broken HTML. + $tagstack = array(); + $score = 1; + } + else { + // Add to open tag stack and increment score + array_unshift($tagstack, $tagname); + $score += $tags[$tagname]; + } + if ($tagname == 'a') { + // Check if link points to a node on this site + if (preg_match($node_regexp, $value, $match)) { + $path = drupal_get_normal_path($match[1]); + if (preg_match('!(?:node|book)/(?:view/)?([0-9]+)!i', $path, $match)) { + $linknid = $match[1]; + if ($linknid > 0) { + // Note: ignore links to uncachable nodes to avoid redirect bugs. + $node = db_fetch_object(db_query('SELECT n.title, n.nid, n.vid, r.format FROM {node} n INNER JOIN {node_revisions} r ON n.vid = r.vid WHERE n.nid = %d', $linknid)); + if (filter_format_allowcache($node->format)) { + $link = TRUE; + $linktitle = $node->title; + } + } + } + } + } + } + // A tag change occurred, reset counter. + $tagwords = 0; + } + else { + // Note: use of PREG_SPLIT_DELIM_CAPTURE above will introduce empty values + if ($value != '') { + if ($link) { + // Check to see if the node link text is its URL. If so, we use the target node title instead. + if (preg_match('!^https?://!i', $value)) { + $value = $linktitle; + } + } + $words = search_index_split($value); + foreach ($words as $word) { + // Add word to accumulator + $accum .= $word .' '; + $num = is_numeric($word); + // Check wordlength + if ($num || drupal_strlen($word) >= $minimum_word_size) { + // Normalize numbers + if ($num) { + $word = (int)ltrim($word, '-0'); + } + + // Links score mainly for the target. + if ($link) { + if (!isset($results[$linknid])) { + $results[$linknid] = array(); + } + $results[$linknid][] = $word; + // Reduce score of the link caption in the source. + $focus *= 0.2; + } + // Fall-through + if (!isset($results[0][$word])) { + $results[0][$word] = 0; + } + $results[0][$word] += $score * $focus; + + // Focus is a decaying value in terms of the amount of unique words up to this point. + // From 100 words and more, it decays, to e.g. 0.5 at 500 words and 0.3 at 1000 words. + $focus = min(1, .01 + 3.5 / (2 + count($results[0]) * .015)); + } + $tagwords++; + // Too many words inside a single tag probably mean a tag was accidentally left open. + if (count($tagstack) && $tagwords >= 15) { + $tagstack = array(); + $score = 1; + } + } + } + } + $tag = !$tag; + } + + search_wipe($sid, $type, TRUE); + + // Insert cleaned up data into dataset + db_query("INSERT INTO {search_dataset} (sid, type, data, reindex) VALUES (%d, '%s', '%s', %d)", $sid, $type, $accum, 0); + + // Insert results into search index + foreach ($results[0] as $word => $score) { + // The database will collate similar words (accented and non-accented forms, etc.), + // and the score is additive, so first add and then insert. + db_query("UPDATE {search_index} SET score = score + %d WHERE word = '%s' AND sid = '%d' AND type = '%s'", $score, $word, $sid, $type); + if (!db_affected_rows()) { + db_query("INSERT INTO {search_index} (word, sid, type, score) VALUES ('%s', %d, '%s', %f)", $word, $sid, $type, $score); + } + search_dirty($word); + } + unset($results[0]); + + // Get all previous links from this item. + $result = db_query("SELECT nid, caption FROM {search_node_links} WHERE sid = %d AND type = '%s'", $sid, $type); + $links = array(); + while ($link = db_fetch_object($result)) { + $links[$link->nid] = $link->caption; + } + + // Now store links to nodes. + foreach ($results as $nid => $words) { + $caption = implode(' ', $words); + if (isset($links[$nid])) { + if ($links[$nid] != $caption) { + // Update the existing link and mark the node for reindexing. + db_query("UPDATE {search_node_links} SET caption = '%s' WHERE sid = %d AND type = '%s' AND nid = %d", $caption, $sid, $type, $nid); + search_touch_node($nid); + } + // Unset the link to mark it as processed. + unset($links[$nid]); + } + else { + // Insert the existing link and mark the node for reindexing. + db_query("INSERT INTO {search_node_links} (caption, sid, type, nid) VALUES ('%s', %d, '%s', %d)", $caption, $sid, $type, $nid); + search_touch_node($nid); + } + } + // Any left-over links in $links no longer exist. Delete them and mark the nodes for reindexing. + foreach ($links as $nid => $caption) { + db_query("DELETE FROM {search_node_links} WHERE sid = %d AND type = '%s' AND nid = %d", $sid, $type, $nid); + search_touch_node($nid); + } +} + +/** + * Change a node's changed timestamp to 'now' to force reindexing. + * + * @param $nid + * The nid of the node that needs reindexing. + */ +function search_touch_node($nid) { + db_query("UPDATE {search_dataset} SET reindex = %d WHERE sid = %d AND type = 'node'", time(), $nid); +} + +/** + * Implementation of hook_nodeapi(). + */ +function search_nodeapi(&$node, $op, $teaser = NULL, $page = NULL) { + switch ($op) { + // Transplant links to a node into the target node. + case 'update index': + $result = db_query("SELECT caption FROM {search_node_links} WHERE nid = %d", $node->nid); + $output = array(); + while ($link = db_fetch_object($result)) { + $output[] = $link->caption; + } + return '<a>('. implode(', ', $output) .')</a>'; + // Reindex the node when it is updated. The node is automatically indexed + // when it is added, simply by being added to the node table. + case 'update': + search_touch_node($node->nid); + break; + } +} + +/** + * Implementation of hook_comment(). + */ +function search_comment($a1, $op) { + switch ($op) { + // Reindex the node when comments are added or changed + case 'insert': + case 'update': + case 'delete': + case 'publish': + case 'unpublish': + search_touch_node(is_array($a1) ? $a1['nid'] : $a1->nid); + break; + } +} + +/** + * Extract a module-specific search option from a search query. e.g. 'type:book' + */ +function search_query_extract($keys, $option) { + if (preg_match('/(^| )'. $option .':([^ ]*)( |$)/i', $keys, $matches)) { + return $matches[2]; + } +} + +/** + * Return a query with the given module-specific search option inserted in. + * e.g. 'type:book'. + */ +function search_query_insert($keys, $option, $value = '') { + if (search_query_extract($keys, $option)) { + $keys = trim(preg_replace('/(^| )'. $option .':[^ ]*/i', '', $keys)); + } + if ($value != '') { + $keys .= ' '. $option .':'. $value; + } + return $keys; +} + +/** + * Parse a search query into SQL conditions. + * + * We build two queries that matches the dataset bodies. @See do_search for + * more about these. + * + * @param $text + * The search keys. + * @return + * A list of six elements. + * * A series of statements AND'd together which will be used to provide all + * possible matches. + * * Arguments for this query part. + * * A series of exact word matches OR'd together. + * * Arguments for this query part. + * * A bool indicating whether this is a simple query or not. Negative + * terms, presence of both AND / OR make this FALSE. + * * A bool indicating the presence of a lowercase or. Maybe the user + * wanted to use OR. + */ +function search_parse_query($text) { + $keys = array('positive' => array(), 'negative' => array()); + + // Tokenize query string + preg_match_all('/ (-?)("[^"]+"|[^" ]+)/i', ' '. $text, $matches, PREG_SET_ORDER); + + if (count($matches) < 1) { + return NULL; + } + + // Classify tokens + $or = FALSE; + $warning = ''; + $simple = TRUE; + foreach ($matches as $match) { + $phrase = FALSE; + // Strip off phrase quotes + if ($match[2]{0} == '"') { + $match[2] = substr($match[2], 1, -1); + $phrase = TRUE; + $simple = FALSE; + } + // Simplify keyword according to indexing rules and external preprocessors + $words = search_simplify($match[2]); + // Re-explode in case simplification added more words, except when matching a phrase + $words = $phrase ? array($words) : preg_split('/ /', $words, -1, PREG_SPLIT_NO_EMPTY); + // Negative matches + if ($match[1] == '-') { + $keys['negative'] = array_merge($keys['negative'], $words); + } + // OR operator: instead of a single keyword, we store an array of all + // OR'd keywords. + elseif ($match[2] == 'OR' && count($keys['positive'])) { + $last = array_pop($keys['positive']); + // Starting a new OR? + if (!is_array($last)) { + $last = array($last); + } + $keys['positive'][] = $last; + $or = TRUE; + continue; + } + // AND operator: implied, so just ignore it + elseif ($match[2] == 'AND' || $match[2] == 'and') { + $warning = $match[2]; + continue; + } + + // Plain keyword + else { + if ($match[2] == 'or') { + $warning = $match[2]; + } + if ($or) { + // Add to last element (which is an array) + $keys['positive'][count($keys['positive']) - 1] = array_merge($keys['positive'][count($keys['positive']) - 1], $words); + } + else { + $keys['positive'] = array_merge($keys['positive'], $words); + } + } + $or = FALSE; + } + + // Convert keywords into SQL statements. + $query = array(); + $query2 = array(); + $arguments = array(); + $arguments2 = array(); + $matches = 0; + $simple_and = FALSE; + $simple_or = FALSE; + // Positive matches + foreach ($keys['positive'] as $key) { + // Group of ORed terms + if (is_array($key) && count($key)) { + $simple_or = TRUE; + $queryor = array(); + $any = FALSE; + foreach ($key as $or) { + list($q, $num_new_scores) = _search_parse_query($or, $arguments2); + $any |= $num_new_scores; + if ($q) { + $queryor[] = $q; + $arguments[] = $or; + } + } + if (count($queryor)) { + $query[] = '('. implode(' OR ', $queryor) .')'; + // A group of OR keywords only needs to match once + $matches += ($any > 0); + } + } + // Single ANDed term + else { + $simple_and = TRUE; + list($q, $num_new_scores, $num_valid_words) = _search_parse_query($key, $arguments2); + if ($q) { + $query[] = $q; + $arguments[] = $key; + if (!$num_valid_words) { + $simple = FALSE; + } + // Each AND keyword needs to match at least once + $matches += $num_new_scores; + } + } + } + if ($simple_and && $simple_or) { + $simple = FALSE; + } + // Negative matches + foreach ($keys['negative'] as $key) { + list($q) = _search_parse_query($key, $arguments2, TRUE); + if ($q) { + $query[] = $q; + $arguments[] = $key; + $simple = FALSE; + } + } + $query = implode(' AND ', $query); + + // Build word-index conditions for the first pass + $query2 = substr(str_repeat("i.word = '%s' OR ", count($arguments2)), 0, -4); + + return array($query, $arguments, $query2, $arguments2, $matches, $simple, $warning); +} + +/** + * Helper function for search_parse_query(); + */ +function _search_parse_query(&$word, &$scores, $not = FALSE) { + $num_new_scores = 0; + $num_valid_words = 0; + // Determine the scorewords of this word/phrase + if (!$not) { + $split = explode(' ', $word); + foreach ($split as $s) { + $num = is_numeric($s); + if ($num || drupal_strlen($s) >= variable_get('minimum_word_size', 3)) { + $s = $num ? ((int)ltrim($s, '-0')) : $s; + if (!isset($scores[$s])) { + $scores[$s] = $s; + $num_new_scores++; + } + $num_valid_words++; + } + } + } + // Return matching snippet and number of added words + return array("d.data ". ($not ? 'NOT ' : '') ."LIKE '%% %s %%'", $num_new_scores, $num_valid_words); +} + +/** + * Do a query on the full-text search index for a word or words. + * + * This function is normally only called by each module that support the + * indexed search (and thus, implements hook_update_index()). + * + * Results are retrieved in two logical passes. However, the two passes are + * joined together into a single query. And in the case of most simple + * queries the second pass is not even used. + * + * The first pass selects a set of all possible matches, which has the benefit + * of also providing the exact result set for simple "AND" or "OR" searches. + * + * The second portion of the query further refines this set by verifying + * advanced text conditions (such negative or phrase matches) + * + * @param $keywords + * A search string as entered by the user. + * + * @param $type + * A string identifying the calling module. + * + * @param $join1 + * (optional) Inserted into the JOIN part of the first SQL query. + * For example "INNER JOIN {node} n ON n.nid = i.sid". + * + * @param $where1 + * (optional) Inserted into the WHERE part of the first SQL query. + * For example "(n.status > %d)". + * + * @param $arguments1 + * (optional) Extra SQL arguments belonging to the first query. + * + * @param $columns2 + * (optional) Inserted into the SELECT pat of the second query. Must contain + * a column selected as 'score'. + * defaults to 'i.relevance AS score' + * + * @param $join2 + * (optional) Inserted into the JOIN par of the second SQL query. + * For example "INNER JOIN {node_comment_statistics} n ON n.nid = i.sid" + * + * @param $arguments2 + * (optional) Extra SQL arguments belonging to the second query parameter. + * + * @param $sort_parameters + * (optional) SQL arguments for sorting the final results. + * Default: 'ORDER BY score DESC' + * + * @return + * An array of SIDs for the search results. + * + * @ingroup search + */ +function do_search($keywords, $type, $join1 = '', $where1 = '1', $arguments1 = array(), $columns2 = 'i.relevance AS score', $join2 = '', $arguments2 = array(), $sort_parameters = 'ORDER BY score DESC') { + $query = search_parse_query($keywords); + + if ($query[2] == '') { + form_set_error('keys', t('You must include at least one positive keyword with @count characters or more.', array('@count' => variable_get('minimum_word_size', 3)))); + } + if ($query[6]) { + if ($query[6] == 'or') { + drupal_set_message(t('Search for either of the two terms with uppercase <strong>OR</strong>. For example, <strong>cats OR dogs</strong>.')); + } + } + if ($query === NULL || $query[0] == '' || $query[2] == '') { + return array(); + } + + // Build query for keyword normalization. + $conditions = "$where1 AND ($query[2]) AND i.type = '%s'"; + $arguments1 = array_merge($arguments1, $query[3], array($type)); + $join = "INNER JOIN {search_total} t ON i.word = t.word $join1"; + if (!$query[5]) { + $conditions .= " AND ($query[0])"; + $arguments1 = array_merge($arguments1, $query[1]); + $join .= " INNER JOIN {search_dataset} d ON i.sid = d.sid AND i.type = d.type"; + } + + // Calculate maximum keyword relevance, to normalize it. + $select = "SELECT SUM(i.score * t.count) AS score FROM {search_index} i $join WHERE $conditions GROUP BY i.type, i.sid HAVING COUNT(*) >= %d ORDER BY score DESC"; + $arguments = array_merge($arguments1, array($query[4])); + $normalize = db_result(db_query_range($select, $arguments, 0, 1)); + if (!$normalize) { + return array(); + } + $columns2 = str_replace('i.relevance', '('. (1.0 / $normalize) .' * SUM(i.score * t.count))', $columns2); + + // Build query to retrieve results. + $select = "SELECT i.type, i.sid, $columns2 FROM {search_index} i $join $join2 WHERE $conditions GROUP BY i.type, i.sid HAVING COUNT(*) >= %d"; + $count_select = "SELECT COUNT(*) FROM ($select) n1"; + $arguments = array_merge($arguments2, $arguments1, array($query[4])); + + // Do actual search query + $result = pager_query("$select $sort_parameters", 10, 0, $count_select, $arguments); + $results = array(); + while ($item = db_fetch_object($result)) { + $results[] = $item; + } + return $results; +} + +/** + * Helper function for grabbing search keys. + */ +function search_get_keys() { + static $return; + if (!isset($return)) { + // Extract keys as remainder of path + // Note: support old GET format of searches for existing links. + $path = explode('/', $_GET['q'], 3); + $keys = empty($_REQUEST['keys']) ? '' : $_REQUEST['keys']; + $return = count($path) == 3 ? $path[2] : $keys; + } + return $return; +} + +/** + * @defgroup search Search interface + * @{ + * The Drupal search interface manages a global search mechanism. + * + * Modules may plug into this system to provide searches of different types of + * data. Most of the system is handled by search.module, so this must be enabled + * for all of the search features to work. + * + * There are three ways to interact with the search system: + * - Specifically for searching nodes, you can implement nodeapi('update index') + * and nodeapi('search result'). However, note that the search system already + * indexes all visible output of a node, i.e. everything displayed normally + * by hook_view() and hook_nodeapi('view'). This is usually sufficient. + * You should only use this mechanism if you want additional, non-visible data + * to be indexed. + * - Implement hook_search(). This will create a search tab for your module on + * the /search page with a simple keyword search form. You may optionally + * implement hook_search_item() to customize the display of your results. + * - Implement hook_update_index(). This allows your module to use Drupal's + * HTML indexing mechanism for searching full text efficiently. + * + * If your module needs to provide a more complicated search form, then you need + * to implement it yourself without hook_search(). In that case, you should + * define it as a local task (tab) under the /search page (e.g. /search/mymodule) + * so that users can easily find it. + */ + +/** + * Render a search form. + * + * @param $action + * Form action. Defaults to "search". + * @param $keys + * The search string entered by the user, containing keywords for the search. + * @param $type + * The type of search to render the node for. Must be the name of module + * which implements hook_search(). Defaults to 'node'. + * @param $prompt + * A piece of text to put before the form (e.g. "Enter your keywords") + * @return + * An HTML string containing the search form. + */ +function search_form(&$form_state, $action = '', $keys = '', $type = NULL, $prompt = NULL) { + + // Add CSS + drupal_add_css(drupal_get_path('module', 'search') .'/search.css', 'module', 'all', FALSE); + + if (!$action) { + $action = url('search/'. $type); + } + if (is_null($prompt)) { + $prompt = t('Enter your keywords'); + } + + $form = array( + '#action' => $action, + '#attributes' => array('class' => 'search-form'), + ); + $form['module'] = array('#type' => 'value', '#value' => $type); + $form['basic'] = array('#type' => 'item', '#title' => $prompt); + $form['basic']['inline'] = array('#prefix' => '<div class="container-inline">', '#suffix' => '</div>'); + $form['basic']['inline']['keys'] = array( + '#type' => 'textfield', + '#title' => '', + '#default_value' => $keys, + '#size' => $prompt ? 40 : 20, + '#maxlength' => 255, + ); + // processed_keys is used to coordinate keyword passing between other forms + // that hook into the basic search form. + $form['basic']['inline']['processed_keys'] = array('#type' => 'value', '#value' => array()); + $form['basic']['inline']['submit'] = array('#type' => 'submit', '#value' => t('Search')); + + return $form; +} + +/** + * Form builder; Output a search form for the search block and the theme's search box. + * + * @ingroup forms + * @see search_box_form_submit() + * @see theme_search_box_form() + */ +function search_box(&$form_state, $form_id) { + $form[$form_id] = array( + '#title' => t('Search this site'), + '#type' => 'textfield', + '#size' => 15, + '#default_value' => '', + '#attributes' => array('title' => t('Enter the terms you wish to search for.')), + ); + $form['submit'] = array('#type' => 'submit', '#value' => t('Search')); + $form['#submit'][] = 'search_box_form_submit'; + $form['#validate'][] = 'search_box_form_validate'; + + return $form; +} + +/** + * Process a block search form submission. + */ +function search_box_form_submit($form, &$form_state) { + $form_id = $form['form_id']['#value']; + $form_state['redirect'] = 'search/node/'. trim($form_state['values'][$form_id]); +} + +/** + * Process variables for search-theme-form.tpl.php. + * + * The $variables array contains the following arguments: + * - $form + * + * @see search-theme-form.tpl.php + */ +function template_preprocess_search_theme_form(&$variables) { + $variables['search'] = array(); + $hidden = array(); + // Provide variables named after form keys so themers can print each element independently. + foreach (element_children($variables['form']) as $key) { + $type = $variables['form'][$key]['#type']; + if ($type == 'hidden' || $type == 'token') { + $hidden[] = drupal_render($variables['form'][$key]); + } + else { + $variables['search'][$key] = drupal_render($variables['form'][$key]); + } + } + // Hidden form elements have no value to themers. No need for separation. + $variables['search']['hidden'] = implode($hidden); + // Collect all form elements to make it easier to print the whole form. + $variables['search_form'] = implode($variables['search']); +} + +/** + * Process variables for search-block-form.tpl.php. + * + * The $variables array contains the following arguments: + * - $form + * + * @see search-block-form.tpl.php + */ +function template_preprocess_search_block_form(&$variables) { + $variables['search'] = array(); + $hidden = array(); + // Provide variables named after form keys so themers can print each element independently. + foreach (element_children($variables['form']) as $key) { + $type = $variables['form'][$key]['#type']; + if ($type == 'hidden' || $type == 'token') { + $hidden[] = drupal_render($variables['form'][$key]); + } + else { + $variables['search'][$key] = drupal_render($variables['form'][$key]); + } + } + // Hidden form elements have no value to themers. No need for separation. + $variables['search']['hidden'] = implode($hidden); + // Collect all form elements to make it easier to print the whole form. + $variables['search_form'] = implode($variables['search']); +} + +/** + * Perform a standard search on the given keys, and return the formatted results. + */ +function search_data($keys = NULL, $type = 'node') { + + if (isset($keys)) { + if (module_hook($type, 'search')) { + $results = module_invoke($type, 'search', 'search', $keys); + if (isset($results) && is_array($results) && count($results)) { + if (module_hook($type, 'search_page')) { + return module_invoke($type, 'search_page', $results); + } + else { + return theme('search_results', $results, $type); + } + } + } + } +} + +/** + * Returns snippets from a piece of text, with certain keywords highlighted. + * Used for formatting search results. + * + * @param $keys + * A string containing a search query. + * + * @param $text + * The text to extract fragments from. + * + * @return + * A string containing HTML for the excerpt. + */ +function search_excerpt($keys, $text) { + // We highlight around non-indexable or CJK characters. + $boundary = '(?:(?<=['. PREG_CLASS_SEARCH_EXCLUDE . PREG_CLASS_CJK .'])|(?=['. PREG_CLASS_SEARCH_EXCLUDE . PREG_CLASS_CJK .']))'; + + // Extract positive keywords and phrases + preg_match_all('/ ("([^"]+)"|(?!OR)([^" ]+))/', ' '. $keys, $matches); + $keys = array_merge($matches[2], $matches[3]); + + // Prepare text + $text = ' '. strip_tags(str_replace(array('<', '>'), array(' <', '> '), $text)) .' '; + array_walk($keys, '_search_excerpt_replace'); + $workkeys = $keys; + + // Extract a fragment per keyword for at most 4 keywords. + // First we collect ranges of text around each keyword, starting/ending + // at spaces. + // If the sum of all fragments is too short, we look for second occurrences. + $ranges = array(); + $included = array(); + $length = 0; + while ($length < 256 && count($workkeys)) { + foreach ($workkeys as $k => $key) { + if (strlen($key) == 0) { + unset($workkeys[$k]); + unset($keys[$k]); + continue; + } + if ($length >= 256) { + break; + } + // Remember occurrence of key so we can skip over it if more occurrences + // are desired. + if (!isset($included[$key])) { + $included[$key] = 0; + } + // Locate a keyword (position $p), then locate a space in front (position + // $q) and behind it (position $s) + if (preg_match('/'. $boundary . $key . $boundary .'/iu', $text, $match, PREG_OFFSET_CAPTURE, $included[$key])) { + $p = $match[0][1]; + if (($q = strpos($text, ' ', max(0, $p - 60))) !== FALSE) { + $end = substr($text, $p, 80); + if (($s = strrpos($end, ' ')) !== FALSE) { + $ranges[$q] = $p + $s; + $length += $p + $s - $q; + $included[$key] = $p + 1; + } + else { + unset($workkeys[$k]); + } + } + else { + unset($workkeys[$k]); + } + } + else { + unset($workkeys[$k]); + } + } + } + + // If we didn't find anything, return the beginning. + if (count($ranges) == 0) { + return truncate_utf8($text, 256) .' ...'; + } + + // Sort the text ranges by starting position. + ksort($ranges); + + // Now we collapse overlapping text ranges into one. The sorting makes it O(n). + $newranges = array(); + foreach ($ranges as $from2 => $to2) { + if (!isset($from1)) { + $from1 = $from2; + $to1 = $to2; + continue; + } + if ($from2 <= $to1) { + $to1 = max($to1, $to2); + } + else { + $newranges[$from1] = $to1; + $from1 = $from2; + $to1 = $to2; + } + } + $newranges[$from1] = $to1; + + // Fetch text + $out = array(); + foreach ($newranges as $from => $to) { + $out[] = substr($text, $from, $to - $from); + } + $text = (isset($newranges[0]) ? '' : '... ') . implode(' ... ', $out) .' ...'; + + // Highlight keywords. Must be done at once to prevent conflicts ('strong' and '<strong>'). + $text = preg_replace('/'. $boundary .'('. implode('|', $keys) .')'. $boundary .'/iu', '<strong>\0</strong>', $text); + return $text; +} + +/** + * @} End of "defgroup search". + */ + +/** + * Helper function for array_walk in search_except. + */ +function _search_excerpt_replace(&$text) { + $text = preg_quote($text, '/'); +} + +function search_forms() { + $forms['search_theme_form']= array( + 'callback' => 'search_box', + 'callback arguments' => array('search_theme_form'), + ); + $forms['search_block_form']= array( + 'callback' => 'search_box', + 'callback arguments' => array('search_block_form'), + ); + return $forms; +}