/core/utils/MySql.php

<?php

class MySql

{

	static public $logFile = null;



	static public $defaultLink = null;



	static public function initDb(){

		self::$defaultLink = self::connect(DB_SERVERNAME, DB_USERNAME, DB_PASS);

		self::select_db(DB_NAME);

		$sql = 'SET NAMES "utf8"';

		self::query($sql);

	}



	static public function logError($code, $error)

	{

		if (self::$logFile === null)

			return;



		$f = @fopen(self::$logFile, "a");

		if (!$f)

			return;

		$d = date("Y-m-d H:i:s");



		$b = array_slice(debug_backtrace(), 1);

		$trace = "";

		foreach ($b as $k=>$place)

			$trace .= "  {$place["file"]}, line {$place["line"]}: {$place["function"]}\n";



		$url = "";

		if (isset($_SERVER['REQUEST_URI']))

			$url = $_SERVER['REQUEST_URI']."\n";



		$st = "";

		if (isset($_SERVER['REQUEST_TIME']))

			$st = "\nrequest time: ".date("Y-m-d H:i:s", $_SERVER['REQUEST_TIME'])."\n";



		fwrite($f, "{$d}{$st} {$error}\n{$trace}{$url}{$code}\n\n");

		fclose($f);

	}



	/**

	 * Wrapper for mysql_query, to extend it with logging abilities

	 *

	 * @param string $sql

	 * @param resource $link

	 * @param array $handledCodes 2DO! which mysql error codes are handled by caller, and 

	 *                            therefore shouldnt be written to log

	 * @param int $timeThreshold 2DO! all queries taking longer than this value (sec) are written 

	 *                           to error log. 0 for no limit.

	 * @return resource

	 */

	static public function query($sql, $link = null, $handledCodes = array(), &$retCode = null, $timeThreshold = 10)

	{

		if ($link === null)

			$link = self::$defaultLink;



		$res = Mysql::_query($sql, $link);

		$n = Mysql::errno($link);

		if ($n)

			$e = Mysql::error($link);



		// if not handled by application, try handling (just exception, to prevent further processing):

		//  2002 Can't connect to local MySQL server through socket '%s' (%d)

		//  2003 Can't connect to MySQL server on '%s' (%d)

		if (($n == 2002 || $n == 2003) && !in_array($n, $handledCodes))

		{

			Mysql::logError($n, $e);

			throw new Exception("Mysql: unable to connect");

		}



		// if not handled by application, try handling (autoreconnect):

		//  2006 Mysql server has gone away

		//  2013 Lost connection during query

		if (($n == 2006 || $n == 2013) && !in_array($n, $handledCodes))

		{

			if (!Mysql::ping($link))

			{

				$e = Mysql::error($link);

				Mysql::logError($sql, "{$n}: {$e} // ping reconnect failed");

				throw new Exception("Mysql: connection lost, ping reconnect failed");

			}



			$res = Mysql::_query($sql, $link);

			$n = Mysql::errno($link);

			if ($n)

				$e = Mysql::error($link)." // after ping reconnect";

		}



		// if not handled by application, try handling (just retry query):

		//  1205 Lock wait timeout

		if ($n == 1205 && !in_array($n, $handledCodes))

			if (isset($_SERVER['REQUEST_TIME']) && $_SERVER['REQUEST_TIME'] > time() - 1)

			{

				$res = Mysql::_query($sql, $link);

				$n = Mysql::errno($link);

				if ($n)

					$e = Mysql::error($link)." // after retry";

			}



		if ($n && !in_array($n, $handledCodes))

		{

			//$e = Mysql::error($link);

			Mysql::logError($sql, "{$n}: {$e}");

		}

		else if (func_num_args() >= 4)

			$retCode = $n;



		return $res;

	}



	static function query_row($sql, $link = null)

	{

		if ($link === null)

			$link = self::$defaultLink;



		$ret = array();



		$res = Mysql::query($sql, $link);

		if (!empty($res)){

			if ($r = mysql_fetch_assoc($res)){

				$ret = $r;

			}

			mysql_free_result($res);

		}



		return $ret;

	}



	static function query_array($sql, $index_by = '', $link = null)

	{

		if ($link === null)

			$link = self::$defaultLink;



		$ret = array();

		

		$res = Mysql::query($sql, $link);

		

		if (!empty($res)){

			while($r = mysql_fetch_assoc($res)){

				if ($index_by == ''){

					$ret[] = $r;

				}else{

					$ret[$r[$index_by]] = $r;

				}

			}

		mysql_free_result($res);

		}

		

		return $ret;

	}



	static function insert_array($table_name, $arr, $link = null)

	{

		if ($link === null)

			$link = self::$defaultLink;



		$names = implode(', ', array_keys($arr));

		$values = implode(', ', array_values($arr));



		Mysql::query(

				"insert into $table_name($names) values($values)", $link

			    );



		if ($link === null)

			return mysql_insert_id();

		else 

			return mysql_insert_id($nk);

	}



	static function query_grouped_array($sql, $keys, $link = null)

	{

		if ($link === null)

			$link = self::$defaultLink;



		$ret = array();



		$kn = count($keys);



		$res = Mysql::query($sql, $link);

		while($r = mysql_fetch_assoc($res)){

			$cn = & $ret;

			for ($i = 0; $i < $kn; $i++){

				if ($i < $kn - 1){

					if (!isset($cn[$r[$keys[$i]]])){

						$cn[$r[$keys[$i]]] = array();

					}

					$cn = & $cn[$r[$keys[$i]]];

				}else{

					$cn[$r[$keys[$i]]] = $r;

				}

			}

		}

		mysql_free_result($res);



		return $ret;

	}



	static function query_iterator($sql, $link=null)

	{

		if ($link === null)

			$link = self::$defaultLink;



		// returns object implementing Iterator for $sql /// use in foreach only ... NOT seekable

		// or throws Exceptions

		// first column will be extracted also as key

		//  foreach ( $qi as   $k => $v) // will make, for instance

		// 		$k = 12343

		//		$v = array('id'=> '12343', 'data' => 'some data')

		return new QueryIterator($sql, $link);

	}



	static function real_escape_string($s, $link=null)

	{

		if ($link === null)

			$link = self::$defaultLink;



		if ($link !== null)

			return mysql_real_escape_string($s, $link);

		else 

			return mysql_real_escape_string($s);

	}



	static function error($link=null)

	{

		if ($link === null)

			$link = self::$defaultLink;



		if ($link !== null)

			return mysql_error($link);

		else 

			return mysql_error();

	}



	static function errno($link=null)

	{

		if ($link === null)

			$link = self::$defaultLink;



		if ($link !== null)

			return mysql_errno($link);

		else 

			return mysql_errno();

	}



	static function select_db($dbName, $link=null)

	{

		if ($link === null)

			$link = self::$defaultLink;



		if ($link !== null)

			return mysql_select_db($dbName, $link);

		else 

			return mysql_select_db($dbName);

	}



	static function ping($link=null)

	{

		if ($link === null)

			$link = self::$defaultLink;



		if ($link !== null)

			return mysql_ping($link);

		else 

			return mysql_ping();

	}



	static function _query($sql, $link=null)

	{

		if ($link !== null)

			return mysql_query($sql, $link);

		else 

			return mysql_query($sql);

	}



	static function insert_id($link=null)

	{

		if ($link === null)

			$link = self::$defaultLink;



		if ($link !== null)

			return mysql_insert_id($link);

		else 

			return mysql_insert_id();

	}



	static function affected_rows($link=null)

	{

		if ($link === null)

			$link = self::$defaultLink;



		if ($link !== null)

			return mysql_affected_rows($link);

		else 

			return mysql_affected_rows();

	}



	static $linkCache = array();



	static function connect($server, $username, $password)

	{

		$hash = md5(serialize(array($server, $username, $password)));



		if (!isset(self::$linkCache[$hash]))

		{

			$link = mysql_connect($server, $username, $password);

			if (!$link)

			{

				$n = Mysql::errno();

				$e = Mysql::error();

				Mysql::logError("connect", "{$n}: {$e}");

			}

			else 

			{

				Mysql::query("set character_set_client='utf8'", $link);

				Mysql::query("set character_set_connection='utf8'", $link);

				Mysql::query("set character_set_results='utf8'", $link);

			}



			self::$linkCache[$hash] = $link;

		}



		return self::$linkCache[$hash];

	}

}



class QueryIterator implements Iterator {

	function __construct($sql, $link){

		$this->sql = $sql;

		$this->link = $link;	

		$this->res = null;

		$this->cur = false;

		$this->key = null;

	}

	function current(){

		return $this->cur;

	}

	function key(){

		if ($this->key){

			return $this->cur[$this->key];			

		}

		return false;

	}

	function valid(){

		return ($this->cur !== false);

	}

	function next(){

		$this->cur = ($this->res) ? mysql_fetch_assoc($this->res) : false;

		return $this->current();

	}

	function rewind(){

		if ($this->res){

			mysql_free_result($this->res);

			$this->res = null;

		}

		$this->res = Mysql::query($this->sql, $this->link);

		$this->next();



		// getting index for key collumn

		if ($this->cur){

			$k = array_keys($this->cur);

			$this->key = $k[0];

		}else{

			$this->key = false;

		}

	}

	function __destruct(){

		if ($this->res) {

			mysql_free_result($this->res);

		}

	}

}



?>