Extension:DataInvoker

require_once("$IP/extensions/DataInvoker/DataInvoker.php");

<?php
/*
 Permission is hereby granted, free of charge, to any person
 obtaining a copy of this software and associated documentation
 files (the "Software"), to deal in the Software without
 restriction, including without limitation the rights to use,
 copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the
 Software is furnished to do so, subject to the following
 conditions:
 
 The above copyright notice and this permission notice shall be
 included in all copies or substantial portions of the Software.
 
 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 OTHER DEALINGS IN THE SOFTWARE.
 
*/
 
$wgExtensionCredits['parserhook'][] = array(
'name'         => 'DataInvoker',
'version'      => '0.3b',
'description'  => 'Allows retrieving data from a database',
'author'       => 'Xudong Yang',
'url'          => 'http://www.mediawiki.org/wiki/Extension:DataInvoker',
);
 
$wgExtensionFunctions[] = 'wfDataInvoker';
 
$wgHooks['LanguageGetMagic'][] = 'wfDataInvokerLanguageGetMagic';
 
function wfDataInvoker ( ) {
    global $wgParser, $wgExtDataInvoker;
    global $wgDataInvokerHostName, $wgDataInvokerUserName,
        $wgDataInvokerPassword, $wgDataInvokerDatabase;
 
    $wgExtDataInvoker = new ExtDataInvoker ( );
    if(!$wgDataInvokerHostName) $wgDataInvokerHostName = 'localhost';
    if(!$wgDataInvokerUserName) $wgDataInvokerUserName = 'dbuser';
    if(!$wgDataInvokerPassword) $wgDataInvokerPassword = 'dbpass';
    if(!$wgDataInvokerDatabase) $wgDataInvokerDatabase = 'dbname';
 
    $wgParser->setFunctionHook('doquery', array(&$wgExtDataInvoker,'doQuery'));
    $wgParser->setFunctionHook('rawquery', array(&$wgExtDataInvoker,'rawQuery'));
    $wgParser->setFunctionHook('getdata', array(&$wgExtDataInvoker,'getData'));
    $wgParser->setFunctionHook('escapestr', array(&$wgExtDataInvoker,'escapeStr'));
 
    $wgParser->mDataInvokerUnnamedHandleCount = 0;
}
 
function wfDataInvokerLanguageGetMagic( &$magicWords, $langCode = "en" ) {
    switch ( $langCode ) {
        default:
            $magicWords['doquery'] = array ( 0, 'doquery' );
            $magicWords['rawquery'] = array ( 0, 'rawquery' );
            $magicWords['getdata'] = array ( 0, 'getdata' );
            $magicWords['escapestr'] = array ( 0, 'escapestr' );
    }
    return true;
}
 
class DIError extends Exception {
    public function __construct($msg){
        $this->message = '<strong class="error">DataInvoker Error: ' . $msg . '</strong>';
    }
}
 
class ExtDataInvoker {
    var $DBConn;
 
    /******** PRIVATE FUNCTIONS ********/
 
    function initConnection() {
        global $wgDataInvokerHostName, $wgDataInvokerUserName,
            $wgDataInvokerPassword, $wgDataInvokerDatabase;
        $this->DBConn = Database::newFromParams($wgDataInvokerHostName, $wgDataInvokerUserName, $wgDataInvokerPassword, $wgDataInvokerDatabase);
    }
 
    function tableName($name) {
        if ( $name{0} != '`' ) {
            # Standard quoting
            $name = "`$name`";
        }
        return $name;
    }
 
    function replode(&$args, $funcname, $glue=',', $delimiter=',') {
        $arglist = explode($delimiter, $args);
        foreach ( $arglist as &$arg )
            eval('$arg = '.$funcname.'($arg);');
        unset($arg);
        $args = implode($glue, $arglist);
    }
 
    function fetchRetRow ($queryresult, $rownum) {
        if($rownum < 1) throw new DIError('ROWNUM cannot be non-positive');
        for($i = 0; ($i < $rownum) && ($queryrow = $this->DBConn->fetchRow($queryresult)); $i++);     // Fetch the $rownum th row
        // Only keep string-indexed keys
        foreach( $queryrow as $key => $value )
            if(is_int($key))
                unset($queryrow[$key]);
        return $queryrow;
    }
 
    function safeSQL($string){
        if(get_magic_quotes_gpc()) {
            $string = stripslashes($string);
        }
        $badWords = "(delete)|(update)|(union)|(insert)|(drop)|(http)|(--)";
        $string = eregi_replace($badWords, "", $string);
        //$string = mysql_real_escape_string($string);
        return $string;
    }
 
    function cacheResult (&$parser, $querystr, &$handlename, $rownum) {
        $queryresult = $this->DBConn->query($querystr, 'ExtDataInvoker::cacheResult');
        if(!$handlename) {
            $handlename = "_unnamedHandle".($parser->mDataInvokerUnnamedHandleCount++);
        }
        elseif(substr($handlename,0,1)=="_") {
            throw new DIError('HANDLE_NAME cannot begin with underscore');
        }
        $parser->mDataInvokerDataCache[$handlename] = $this->fetchRetRow($queryresult, $rownum);
        $parser->mDataInvokerLastHandleName = $handlename;
        $this->DBConn->freeResult( $queryresult );
    }
 
    /******** PARSER FUNCTIONS ********/
 
    function doQuery (&$parser, $table='', $column='*', $matchcolumn='', $matchvalue='', $orderby='', $order='ASC', $rownum = 1, $handlename='', $debug=false) {
        try {
            $this->initConnection();
 
            // Parse the parameters
            $this->replode($table, '$this->tableName');
            # if($column != '*') $this->replode($column, '$this->DBConn->addQuotes');
            if(!$column) $column = '*';
            $matchcolumn = mysql_real_escape_string($matchcolumn);
            $matchvalue = mysql_real_escape_string($matchvalue);
            # $this->replode($orderby, '$this->DBConn->addQuotes');
            if($order != 'ASC') $order = 'DESC';
 
            // Form the query string
            $querystr = "SELECT $column FROM $table";
            if($matchcolumn && $matchvalue) $querystr .= " WHERE $matchcolumn = '$matchvalue'";
            if($orderby) $querystr .= " ORDER BY $orderby $order";
 
            // Retrieve and cache the data
            $this->cacheResult($parser, $querystr, $handlename, $rownum);
            $ret = '';
            if($debug) $ret.="doQuery: $querystr ; handleName: $handlename";
        }
        catch( DBError $e ) {
            return "<strong class='error'>".$e->getMessage()."</strong>";
        }
        catch( DIError $e ) {
            return $e->getMessage();
        }
        return $ret;
    }
 
    function rawQuery (&$parser, $querystr='', $rownum = 1, $handlename='', $debug=false) {
        try {
            if(strtoupper(substr($querystr, 0, 6)) != 'SELECT')
                throw new DIError('Raw query must begin with SELECT');
            $this->initConnection();
            $querystr = $this->safeSQL($querystr);
 
            // Retrieve and cache the data
            $this->cacheResult($parser, $querystr, $handlename, $rownum);
            $ret = '';
            if($debug) $ret.="rawQuery: $querystr; handleName: $handlename";
        }
        catch( DBError $e ) {
            return "<strong class='error'>".$e->getMessage()."</strong>";
        }
        catch( DIError $e ) {
            return $e->getMessage();
        }
        return $ret;
    }
 
    function getData (&$parser, $key='', $handlename='', $suppresserror=false) {
        try {
            if(!$handlename) $handlename = $parser->mDataInvokerLastHandleName;
            if(!isset($parser->mDataInvokerDataCache[$handlename]))
                throw new DIError ("getData error: No such handle found ($handlename)");
            if(!isset($parser->mDataInvokerDataCache[$handlename][$key]))
                throw new DIError ("getData error: No such key in handle ($key)");
            $ret = $parser->mDataInvokerDataCache[$handlename][$key];
        }
        catch ( DIError $e ) {
            if($suppresserror) return '';
            else return $e->getMessage();
        }
        return $ret;
    }
 
    function escapeStr (&$parser, $str='') {
        try {
            return mysql_real_escape_string($str);
        }
        catch (Exception $e) {
            return $str;
        }
    }
}