/db/db.class.php

<?php

//

// +----------------------------------------------------------------------+

// | PHP version 4.0                                                      |

// +----------------------------------------------------------------------+

// | Copyright (c) 1997-2001 The PHP Group                                |

// +----------------------------------------------------------------------+

// | This source file is subject to version 2.02 of the PHP license,      |

// | that is bundled with this package in the file LICENSE, and is        |

// | available at through the world-wide-web at                           |

// | http://www.php.net/license/2_02.txt.                                 |

// | If you did not receive a copy of the PHP license and are unable to   |

// | obtain it through the world-wide-web, please send a note to          |

// | license@php.net so we can mail you a copy immediately.               |

// +----------------------------------------------------------------------+

// | Authors: Stig Bakken <ssb@fast.no>                                   |

// |          Jan Dankert <phpdb@jandankert.de>                           |

// +----------------------------------------------------------------------+

//



// This is the database abstraction layer. This class was inspired by the

// PHP-Pear-DB package. Thanks to its developers.



/**

 * Darstellung einer Datenbank-Verbindung.

 * F�r die echten DB-Aufrufe werden die entsprechenden

 * Methoden des passenden Clients aufgerufen.

 * 

 * Diese Klasse stammt urspruenglich aus dem PHP-Pear-DB-Projekt und unterliegt

 * daher auch der PHP-licence.

 * 

 * @author Jan Dankert

 * @package openrat.database

 */

class DB

{
	/**
	 * Datenbank-Id.
	 *
	 * @var String
	 */
	var $id;

	
	/**
	 * Konfiguration der Datenbank-Verbindung
	 *
	 * @var Array
	 */
	var $conf;

	
	/**
	 * Kennzeichen, ob die Datenbank verf�gbar ist.
	 *
	 * @var Boolean
	 */
	var $available;

	
	/**
	 * Enth�lt eine Fehlermeldung (sofern verf�gbar).
	 *
	 * @var String
	 */
	var $error;


	/**
	 * Client.

	 * Enth�lt ein Objekt der Klasse db_<type>.
	 *
	 * @var Object
	 */

	var $client;

	

	/**

	 * Schalter, ob eine Transaktion begonnen wurde.

	 * @var boolean

	 */

	var $transactionInProgress = false;
	


	/**
	 * Kontruktor.
	 * Erwartet die Datenbank-Konfiguration als Parameter.
	 *
	 * @param Array Konfiguration der Verbindung
	 * @return Status 'true' wenn Verbindung erfolgreich aufgebaut.
	 */

	public function DB( $conf )

	{
		$this->available = false;

		$this->conf      = $conf;
		
		$this->connect();
		
		return $this->available;

	}

	


	/**
	 * Verbindung zur Datenbank aufbauen.
	 *
	 * @return Status
	 */

	public function connect()

	{
		// Ausfuehren des Systemkommandos vor Verbindungsaufbau
		if	( !empty($this->conf['cmd']))
		{
			$ausgabe = array();
			$rc      = false;

			Logger::debug("Database command executing: ".$this->conf['cmd']);
			exec( $this->conf['cmd'],$ausgabe,$rc );
			
			foreach( $ausgabe as $zeile )
				Logger::debug("Database command output: ".$zeile);
			
			if	( $rc != 0 )
			{
				$this->error     = 'Command failed: '.implode("",$ausgabe);
				$this->available = false; 
				return false;
			}
		}
		
		$type = $this->conf['type'];

		$classname = 'db_'.$type;

		

		if	( ! class_exists($classname) )

		{

			$this->error     = 'Database type "'.$type.'" is not available';

			$this->available = false;

			return false;

		}

		

		// Client instanziieren

		$this->client = & new $classname;



		$ok = $this->client->connect( $this->conf );

		
		if	( ! $ok )
		{
			$this->error     = 'Cannot connect to database: '.$this->client->error;
			$this->available = false;
			return false; 
		}


				

		// SQL nach Verbindungsaufbau ausfuehren.

		if	( isset($this->conf['connection_sql']) &&  ! empty($this->conf['connection_sql']) )

		{

			$cmd = $this->conf['connection_sql'];

			$ok = $this->client->query($cmd);

			

			if	( ! $ok )

			{

				$this->error     = $this->client->error;

				$this->available = false;

				return false; 

			}

		}

		

		$this->available = true;

		return true;

	}




	/**
	 * Ausfuehren einer Datenbankanfrage.
	 *
	 * @param SQL-Objekt
	 * @return Object (Result)
	 */

	public function query( $query )

	{

		if ( !is_object($query) )

			die('SQL-Query must be an object');

			

		// Vorbereitete Datenbankabfrage ("Prepared Statement")

		if	( isset($this->conf['prepare']) && $this->conf['prepare'] )

		{

			$this->client->clear();

			

			// Statement an die Datenbank schicken

			$this->client->prepare( $query->raw,$query->param );

			

			// Einzelne Parameter an die Anfrage binden

			foreach ($query->param as $name=>$unused)

				$this->client->bind($name,$this->convertCharsetToDatabase($query->data[$name]));

			

			// Ausf�hren...

			$result = $this->client->query($query);

			

			if	( $result === FALSE )

			{

				$this->error = $this->client->error;

				

				Logger::warn('Database error: '.$this->error);

				Http::serverError('Database Error',$this->error);

			}

					

			return $result;

		}

		else

		{

			// Es handelt sich um eine nicht-vorbereitete Anfrage. Das gesamte

			// SQL wird durch die SQL-Klasse erzeugt, dort werden auch die Parameter

			// in die Abfrage gesetzt.

			

			$escape_function = method_exists($this->client,'escape')?$this->client->escape():'addslashes';

			$flatQuery = $query->getQuery( $escape_function );



			$flatQuery = $this->convertCharsetToDatabase($flatQuery);

			
			Logger::trace('DB query on DB '.$this->id."\n".$query->raw);

	
			$result = $this->client->query($flatQuery);
			
			if	( $result === FALSE )
			{
				$this->error = $this->client->error;
				
				if	( true )
				{

					Logger::warn('Database error: '.$this->error);
					Http::serverError('Database Error',$this->error);
				}
			}
	

			if	( isset($this->conf['autocommit']) && @$this->conf['autocommit'])

				if	( method_exists($this->client,'commit') )

					$this->client->commit();

			

			return $result;

		}

	}




	/**
	 * Ermittelt genau 1 Datenbankergebnis aus einer SQL-Anfrage.
	 * Falls es mehrere Treffer gibt, wird die 1. Spalte aus der 1. Zeile genommen.
	 *
	 * @param String $query
	 * @return String
	 */

	public function &getOne( $query )

	{

		$none = '';

		$result = $this->query($query);

		

		$row = $this->client->fetchRow( $result,0 );

		$this->client->freeResult($result);



		if	( ! is_array($row) )

			return $none;

			

		array_walk($row,array($this,'convertCharsetFromDatabase'));

		$keys = array_keys($row);

		

		return $row[ $keys[0] ];

	}




	/**
	 * Ermittelt eine Zeile aus der Datenbank.
	 *
	 * @param String $query
	 * @return Array
	 */

	public function &getRow( $query )

	{

		$result = $this->query($query);

		

		if	( $result === FALSE )

		{

			$this->error = $this->client->error;

			

			Logger::warn('Database error: '.$this->error);

			Http::serverError('Database Error',$this->error);

		}



		$row = $this->client->fetchRow( $result,0 );

		$this->client->freeResult($result);



		if	( ! is_array($row) )

			$row = array();



			//Html::debug($row,"vorher");

		$row = $this->convertRowWithCharsetFromDatabase($row);

			//Html::debug($row,"nachher");

			

		return $row;

	}




	/**
	 * Ermittelt eine (die 1.) Spalte aus dem Datenbankergebnis.
	 *
	 * @param String $query
	 * @return Array
	 */

	public function &getCol( $query )

	{

		$result = $this->query($query);



		$i = 0;

		$col = array();

		while( $row = $this->client->fetchRow( $result,$i++ ) )

		{

			if	( empty($row) )

				break;

				

			array_walk($row,array($this,'convertCharsetFromDatabase'));

			$keys = array_keys($row);

			$col[] = $row[ $keys[0] ];

		}

			

		$this->client->freeResult($result);

		

		return $col;

	}




	/**
	 * Ermittelt ein assoziatives Array aus der Datenbank.
	 *
	 * @param String $query
	 * @param Boolean $force_array
	 * @return Array
	 */

	public function &getAssoc( $query, $force_array = false )

	{

		$results = array();

		$result = $this->query($query);



		$i = 0;

		

		while( $row = $this->client->fetchRow( $result,$i++ ) )

		{

			if	( empty($row) )

				break;



			array_walk($row,array($this,'convertCharsetFromDatabase'));

				

			if	( count($row) > 2 || $force_array )

			{

				// FIXME: Wird offenbar nie ausgeführt.

				$row = $res->fetchRow($i);



				$keys = array_keys($row);

				$key1 = $keys[0];



				unset( $row[$key1] );

				$results[ $row[$key1] ] = $row;

			}

			else

			{

				$keys = array_keys($row);

				$key1 = $keys[0];

				$key2 = $keys[1];



				$results[ $row[$key1] ] = $row[$key2];

			}

		}



		$this->client->freeResult( $result );



		return $results;

	}




	/**
	 * Ermittelt alle Datenbankergebniszeilen.
	 *
	 * @param String $query
	 * @return Array
	 */

	public function &getAll( $query )

	{

		$result = $this->query( $query );



		$results = array();

		$i = 0;



		while( $row = $this->client->fetchRow( $result,$i++ ) )

		{

			array_walk($row,array($this,'convertCharsetFromDatabase'));

			$results[] = $row;

		}



		$this->client->freeResult( $result );

		

		return $results;

	}

	

	

	/**

	 * Startet eine Transaktion.

	 */

	public function start()

	{

		if	( @$this->conf['transaction'])

			if	( method_exists($this->client,'start') )

			{

				$this->transactionInProgress = true;

				$this->client->start();

			}

	}

	

	

	/**

	 * Beendet und best�tigt eine Transaktion.

	 */

	public function commit()

	{

		if	( @$this->conf['transaction'])

			if	( method_exists($this->client,'commit') )

				if	( $this->transactionInProgress )

				{

					$this->client->commit();

					$this->transactionInProgress = false;

				}

	}

	

	/**

	 * Setzt eine Transaktion zur�ck.

	 */

	public function rollback()

	{

		if	( @$this->conf['transaction'])

			if	( method_exists($this->client,'rollback') )

				if	( $this->transactionInProgress )

				{

					$this->client->rollback();

					$this->transactionInProgress = false;

				}

	}

	

	

	private function convertCharsetToDatabase($text)

	{

		//Logger::debug('from '.$text);

		$dbCharset = @$this->conf['charset'];

		if	( !empty($dbCharset) && $dbCharset != 'UTF-8' )

		{

		//	Logger::debug('Converting from UTF-8 to '.$dbCharset);

			if	( !function_exists('iconv') )

				Logger::warn('iconv not available - database charset unchanged. Please '.

				             'enable iconv on your system or transform your database content to UTF-8.');

			else

				$text = iconv('UTF-8',$dbCharset.'//TRANSLIT',$text);

		}

		//Logger::debug('to   '.$text);

		return $text;

		

	}

	

	

	private function convertCharsetFromDatabase($text)

	{

		//Logger::debug('from '.$text);

		$dbCharset = @$this->conf['charset'];

		if	( !empty($dbCharset) && $dbCharset != 'UTF-8' )

		{

			//Logger::debug('Converting to UTF-8 from '.$dbCharset);

			if	( !function_exists('iconv') )

				Logger::warn('iconv not available - database charset unchanged. Please '.

				             'enable iconv on your system or transform your database content to UTF-8.');

			else

				$text = iconv($dbCharset,'UTF-8//TRANSLIT',$text);

		}

		//Logger::debug('to   '.$text);

		return $text;

		

	}

	

	

	private function convertRowWithCharsetFromDatabase($row)

	{

		foreach( $row as $key=>$value)

		{

			$row[$key] = $this->convertCharsetFromDatabase($row[$key]);

		}

		return $row;

	}

	

}





?>