peardb.php

PhpWiki是sourceforge的一个开源项目

<?php // -*-php-*-
rcs_id('$Id: PearDB.php,v 1.87 2005/02/10 19:04:24 rurban Exp $');

require_once('lib/WikiDB/backend.php');
//require_once('lib/FileFinder.php');
//require_once('lib/ErrorManager.php');

class WikiDB_backend_PearDB
extends WikiDB_backend
{
    var $_dbh;

    function WikiDB_backend_PearDB ($dbparams) {
        // Find and include PEAR's DB.php. maybe we should force our private version again...
        // if DB would have exported its version number, it would be easier.
        @require_once('DB/common.php'); // Either our local pear copy or the system one
        // check the version!
        $name = check_php_version(5) ? "escapeSimple" : strtolower("escapeSimple");
        if (!in_array($name, get_class_methods("DB_common"))) {
            $finder = new FileFinder;
            $dir = dirname(__FILE__)."/../../pear";
            $finder->_prepend_to_include_path($dir);
            include_once("$dir/DB/common.php"); // use our version instead.
            if (!in_array($name, get_class_methods("DB_common"))) {
                $pearFinder = new PearFileFinder("lib/pear");
                $pearFinder->includeOnce('DB.php');
            } else {
                include_once("$dir/DB.php");
            }
        } else {
          include_once("DB.php");
        }

        // Install filter to handle bogus error notices from buggy DB.php's.
        // TODO: check the Pear_DB version, but how?
        if (0) {
            global $ErrorManager;
            $ErrorManager->pushErrorHandler(new WikiMethodCb($this, '_pear_notice_filter'));
            $this->_pearerrhandler = true;
        }
        
        // Open connection to database
        $this->_dsn = $dbparams['dsn'];
	$this->_dbparams = $dbparams;
        $this->_lock_count = 0;

        // persistent is usually a DSN option: we override it with a config value.
        //   phptype://username:password@hostspec/database?persistent=false
        $dboptions = array('persistent' => DATABASE_PERSISTENT,
                           'debug' => 2);
        //if (preg_match('/^pgsql/', $this->_dsn)) $dboptions['persistent'] = false;
        $this->_dbh = DB::connect($this->_dsn, $dboptions);
        $dbh = &$this->_dbh;
        if (DB::isError($dbh)) {
            trigger_error(sprintf("Can't connect to database: %s",
                                  $this->_pear_error_message($dbh)),
                          E_USER_ERROR);
        }
        $dbh->setErrorHandling(PEAR_ERROR_CALLBACK,
                               array($this, '_pear_error_callback'));
        $dbh->setFetchMode(DB_FETCHMODE_ASSOC);

        $prefix = isset($dbparams['prefix']) ? $dbparams['prefix'] : '';
        $this->_table_names
            = array('page_tbl'     => $prefix . 'page',
                    'version_tbl'  => $prefix . 'version',
                    'link_tbl'     => $prefix . 'link',
                    'recent_tbl'   => $prefix . 'recent',
                    'nonempty_tbl' => $prefix . 'nonempty');
        $page_tbl = $this->_table_names['page_tbl'];
        $version_tbl = $this->_table_names['version_tbl'];
        $this->page_tbl_fields = "$page_tbl.id AS id, $page_tbl.pagename AS pagename, $page_tbl.hits AS hits";
        $this->version_tbl_fields = "$version_tbl.version AS version, $version_tbl.mtime AS mtime, ".
            "$version_tbl.minor_edit AS minor_edit, $version_tbl.content AS content, $version_tbl.versiondata AS versiondata";

        $this->_expressions
            = array('maxmajor'     => "MAX(CASE WHEN minor_edit=0 THEN version END)",
                    'maxminor'     => "MAX(CASE WHEN minor_edit<>0 THEN version END)",
                    'maxversion'   => "MAX(version)",
                    'notempty'     => "<>''",
                    'iscontent'    => "content<>''");
        
    }
    
    /**
     * Close database connection.
     */
    function close () {
        if (!$this->_dbh)
            return;
        if ($this->_lock_count) {
            trigger_error( "WARNING: database still locked " . '(lock_count = $this->_lock_count)' . "\n<br />",
                          E_USER_WARNING);
        }
        $this->_dbh->setErrorHandling(PEAR_ERROR_PRINT);	// prevent recursive loops.
        $this->unlock('force');

        $this->_dbh->disconnect();

        if (!empty($this->_pearerrhandler)) {
            $GLOBALS['ErrorManager']->popErrorHandler();
        }
    }


    /*
     * Test fast wikipage.
     */
    function is_wiki_page($pagename) {
        $dbh = &$this->_dbh;
        extract($this->_table_names);
        return $dbh->getOne(sprintf("SELECT $page_tbl.id as id"
                                    . " FROM $nonempty_tbl, $page_tbl"
                                    . " WHERE $nonempty_tbl.id=$page_tbl.id"
                                    . "   AND pagename='%s'",
                                    $dbh->escapeSimple($pagename)));
    }
        
    function get_all_pagenames() {
        $dbh = &$this->_dbh;
        extract($this->_table_names);
        return $dbh->getCol("SELECT pagename"
                            . " FROM $nonempty_tbl, $page_tbl"
                            . " WHERE $nonempty_tbl.id=$page_tbl.id");
    }

    function numPages($filter=false, $exclude='') {
        $dbh = &$this->_dbh;
        extract($this->_table_names);
        return $dbh->getOne("SELECT count(*)"
                            . " FROM $nonempty_tbl, $page_tbl"
                            . " WHERE $nonempty_tbl.id=$page_tbl.id");
    }
    
    function increaseHitCount($pagename) {
        $dbh = &$this->_dbh;
        // Hits is the only thing we can update in a fast manner.
        // Note that this will fail silently if the page does not
        // have a record in the page table.  Since it's just the
        // hit count, who cares?
        $dbh->query(sprintf("UPDATE %s SET hits=hits+1 WHERE pagename='%s'",
                            $this->_table_names['page_tbl'],
                            $dbh->escapeSimple($pagename)));
        return;
    }

    /**
     * Read page information from database.
     */
    function get_pagedata($pagename) {
        $dbh = &$this->_dbh;
        //trigger_error("GET_PAGEDATA $pagename", E_USER_NOTICE);
        $result = $dbh->getRow(sprintf("SELECT hits,pagedata FROM %s WHERE pagename='%s'",
                                       $this->_table_names['page_tbl'],
                                       $dbh->escapeSimple($pagename)),
                               DB_FETCHMODE_ASSOC);
        return $result ? $this->_extract_page_data($result) : false;
    }

    function  _extract_page_data($data) {
        if (empty($data)) return array();
        elseif (empty($data['pagedata'])) return $data;
        else {
            $data = array_merge($data, $this->_unserialize($data['pagedata']));
            unset($data['pagedata']);
            return $data;
        }
    }

    function update_pagedata($pagename, $newdata) {
        $dbh = &$this->_dbh;
        $page_tbl = $this->_table_names['page_tbl'];

        // Hits is the only thing we can update in a fast manner.
        if (count($newdata) == 1 && isset($newdata['hits'])) {
            // Note that this will fail silently if the page does not
            // have a record in the page table.  Since it's just the
            // hit count, who cares?
            $dbh->query(sprintf("UPDATE $page_tbl SET hits=%d WHERE pagename='%s'",
                                $newdata['hits'], $dbh->escapeSimple($pagename)));
            return;
        }

        $this->lock(array($page_tbl), true);
        $data = $this->get_pagedata($pagename);
        if (!$data) {
            $data = array();
            $this->_get_pageid($pagename, true); // Creates page record
        }
        
        @$hits = (int)$data['hits'];
        unset($data['hits']);

        foreach ($newdata as $key => $val) {
            if ($key == 'hits')
                $hits = (int)$val;
            else if (empty($val))
                unset($data[$key]);
            else
                $data[$key] = $val;
        }

        /* Portability issue -- not all DBMS supports huge strings 
         * so we need to 'bind' instead of building a simple SQL statment.
         * Note that we do not need to escapeSimple when we bind
        $dbh->query(sprintf("UPDATE $page_tbl"
                            . " SET hits=%d, pagedata='%s'"
                            . " WHERE pagename='%s'",
                            $hits,
                            $dbh->escapeSimple($this->_serialize($data)),
                            $dbh->escapeSimple($pagename)));
        */
        $sth = $dbh->query("UPDATE $page_tbl"
                           . " SET hits=?, pagedata=?"
                           . " WHERE pagename=?",
                           array($hits, $this->_serialize($data), $pagename));
        $this->unlock(array($page_tbl));
    }

    function get_cached_html($pagename) {
        $dbh = &$this->_dbh;
        $page_tbl = $this->_table_names['page_tbl'];
        return $dbh->GetOne(sprintf("SELECT cached_html FROM $page_tbl WHERE pagename='%s'",
                                    $dbh->escapeSimple($pagename)));
    }

    function set_cached_html($pagename, $data) {
        $dbh = &$this->_dbh;
        $page_tbl = $this->_table_names['page_tbl'];
        $sth = $dbh->query("UPDATE $page_tbl"
                           . " SET cached_html=?"
                           . " WHERE pagename=?",
                           array($data, $pagename));
    }

    function _get_pageid($pagename, $create_if_missing = false) {
        
        // check id_cache
        global $request;
        $cache =& $request->_dbi->_cache->_id_cache;
        if (isset($cache[$pagename])) {
            if ($cache[$pagename] or !$create_if_missing) {
                return $cache[$pagename];
            }
        }

        $dbh = &$this->_dbh;
        $page_tbl = $this->_table_names['page_tbl'];
        
        $query = sprintf("SELECT id FROM $page_tbl WHERE pagename='%s'",
                         $dbh->escapeSimple($pagename));

        if (!$create_if_missing)
            return $dbh->getOne($query);

        $id = $dbh->getOne($query);
        if (empty($id)) {
            $this->lock(array($page_tbl), true); // write lock
            $max_id = $dbh->getOne("SELECT MAX(id) FROM $page_tbl");
            $id = $max_id + 1;
            $dbh->query(sprintf("INSERT INTO $page_tbl"
                                . " (id,pagename,hits)"
                                . " VALUES (%d,'%s',0)",
                                $id, $dbh->escapeSimple($pagename)));
            $this->unlock(array($page_tbl));
        }
        return $id;
    }

    function get_latest_version($pagename) {
        $dbh = &$this->_dbh;
        extract($this->_table_names);
        return
            (int)$dbh->getOne(sprintf("SELECT latestversion"
                                      . " FROM $page_tbl, $recent_tbl"
                                      . " WHERE $page_tbl.id=$recent_tbl.id"
                                      . "  AND pagename='%s'",
                                      $dbh->escapeSimple($pagename)));
    }

    function get_previous_version($pagename, $version) {
        $dbh = &$this->_dbh;
        extract($this->_table_names);
        
        return
            (int)$dbh->getOne(sprintf("SELECT version"
                                      . " FROM $version_tbl, $page_tbl"
                                      . " WHERE $version_tbl.id=$page_tbl.id"
                                      . "  AND pagename='%s'"
                                      . "  AND version < %d"
                                      . " ORDER BY version DESC",
                                      /* Non portable and useless anyway with getOne
                                      . " LIMIT 1",
                                      */
                                      $dbh->escapeSimple($pagename),
                                      $version));
    }
    
    /**
     * Get version data.
     *
     * @param $version int Which version to get.
     *
     * @return hash The version data, or false if specified version does not
     *              exist.
     */
    function get_versiondata($pagename, $version, $want_content = false) {
        $dbh = &$this->_dbh;
        extract($this->_table_names);
        extract($this->_expressions);

        assert(is_string($pagename) and $pagename != "");
        assert($version > 0);
        
        //trigger_error("GET_REVISION $pagename $version $want_content", E_USER_NOTICE);
        // FIXME: optimization: sometimes don't get page data?
        if ($want_content) {
            $fields = $this->page_tbl_fields 
                . ",$page_tbl.pagedata as pagedata," 
                . $this->version_tbl_fields;
        }
        else {
            $fields = $this->page_tbl_fields . ","
                . "mtime, minor_edit, versiondata,"
                . "$iscontent AS have_content";
        }

        $result = $dbh->getRow(sprintf("SELECT $fields"
                                       . " FROM $page_tbl, $version_tbl"
                                       . " WHERE $page_tbl.id=$version_tbl.id"
                                       . "  AND pagename='%s'"
                                       . "  AND version=%d",
                                       $dbh->escapeSimple($pagename), $version),
                               DB_FETCHMODE_ASSOC);

        return $this->_extract_version_data($result);
    }

    function _extract_version_data($query_result) {
        if (!$query_result)
            return false;

        $data = $this->_unserialize($query_result['versiondata']);
        
        $data['mtime'] = $query_result['mtime'];
        $data['is_minor_edit'] = !empty($query_result['minor_edit']);
        
        if (isset($query_result['content']))
            $data['%content'] = $query_result['content'];
        elseif ($query_result['have_content'])
            $data['%content'] = true;
        else
            $data['%content'] = '';

        // FIXME: this is ugly.
        if (isset($query_result['pagedata'])) {
            // Query also includes page data.
            // We might as well send that back too...
            unset($query_result['versiondata']);
            $data['%pagedata'] = $this->_extract_page_data($query_result);
        }