server/lib/db.php
2011-08-01 00:07:46 +02:00

399 lines
11 KiB
PHP

<?php
/**
* ownCloud
*
* @author Frank Karlitschek
* @copyright 2010 Frank Karlitschek karlitschek@kde.org
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
* License as published by the Free Software Foundation; either
* version 3 of the License, or any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU AFFERO GENERAL PUBLIC LICENSE for more details.
*
* You should have received a copy of the GNU Affero General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*
*/
/**
* This class manages the access to the database. It basically is a wrapper for
* MDB2 with some adaptions.
*/
class OC_DB {
static private $DBConnection=false;
static private $schema=false;
static private $affected=0;
static private $result=false;
/**
* @brief connects to the database
* @returns true if connection can be established or nothing (die())
*
* Connects to the database as specified in config.php
*/
static public function connect(){
// The global data we need
$CONFIG_DBNAME = OC_Config::getValue( "dbname", "owncloud" );;
$CONFIG_DBHOST = OC_Config::getValue( "dbhost", "" );;
$CONFIG_DBUSER = OC_Config::getValue( "dbuser", "" );;
$CONFIG_DBPASSWORD = OC_Config::getValue( "dbpassword", "" );;
$CONFIG_DBTYPE = OC_Config::getValue( "dbtype", "sqlite" );;
global $SERVERROOT;
$datadir=OC_Config::getValue( "datadirectory", "$SERVERROOT/data" );
// do nothing if the connection already has been established
if(!self::$DBConnection){
// Require MDB2.php (not required in the head of the file so we only load it when needed)
require_once('MDB2.php');
// Prepare options array
$options = array(
'portability' => MDB2_PORTABILITY_ALL,
'log_line_break' => '<br>',
'idxname_format' => '%s',
'debug' => true,
'quote_identifier' => true );
// Add the dsn according to the database type
if( $CONFIG_DBTYPE == 'sqlite' or $CONFIG_DBTYPE == 'sqlite3' ){
// sqlite
$dsn = array(
'phptype' => $CONFIG_DBTYPE,
'database' => "$datadir/$CONFIG_DBNAME.db",
'mode' => '0644' );
}
elseif( $CONFIG_DBTYPE == 'mysql' ){
// MySQL
$dsn = array(
'phptype' => 'mysql',
'username' => $CONFIG_DBUSER,
'password' => $CONFIG_DBPASSWORD,
'hostspec' => $CONFIG_DBHOST,
'database' => $CONFIG_DBNAME );
}
elseif( $CONFIG_DBTYPE == 'pgsql' ){
// PostgreSQL
$dsn = array(
'phptype' => 'pgsql',
'username' => $CONFIG_DBUSER,
'password' => $CONFIG_DBPASSWORD,
'hostspec' => $CONFIG_DBHOST,
'database' => $CONFIG_DBNAME );
}
// Try to establish connection
self::$DBConnection = MDB2::factory( $dsn, $options );
// Die if we could not connect
if( PEAR::isError( self::$DBConnection )){
echo( '<b>can not connect to database, using '.$CONFIG_DBTYPE.'. ('.self::$DBConnection->getUserInfo().')</center>');
$error = self::$DBConnection->getMessage();
error_log( $error);
error_log( self::$DBConnection->getUserInfo());
die( $error );
}
// We always, really always want associative arrays
self::$DBConnection->setFetchMode(MDB2_FETCHMODE_ASSOC);
//we need to function module for query pre-procesing
self::$DBConnection->loadModule('Function');
}
// we are done. great!
return true;
}
/**
* @brief SQL query
* @param $query Query string
* @returns result as MDB2_Result
*
* SQL query via MDB2 query()
*/
static public function query( $query ){
// Optimize the query
$query = self::processQuery( $query );
self::connect();
//fix differences between sql versions
// return the result
$result = self::$DBConnection->exec( $query );
// Die if we have an error (error means: bad query, not 0 results!)
if( PEAR::isError($result)) {
$entry = 'DB Error: "'.$result->getMessage().'"<br />';
$entry .= 'Offending command was: '.$cmd.'<br />';
error_log( $entry );
die( $entry );
}
return $result;
}
/**
* @brief Prepare a SQL query
* @param $query Query string
* @returns prepared SQL query
*
* SQL query via MDB2 prepare(), needs to be execute()'d!
*/
static public function prepare( $query ){
// Optimize the query
$query = self::processQuery( $query );
self::connect();
// return the result
$result = self::$DBConnection->prepare( $query );
// Die if we have an error (error means: bad query, not 0 results!)
if( PEAR::isError($result)) {
$entry = 'DB Error: "'.$result->getMessage().'"<br />';
$entry .= 'Offending command was: '.$query.'<br />';
error_log( $entry );
die( $entry );
}
return $result;
}
/**
* @brief gets last value of autoincrement
* @returns id
*
* MDB2 lastInsertID()
*
* Call this method right after the insert command or other functions may
* cause trouble!
*/
public static function insertid(){
self::connect();
return self::$DBConnection->lastInsertID();
}
/**
* @brief Disconnect
* @returns true/false
*
* This is good bye, good bye, yeah!
*/
public static function disconnect(){
// Cut connection if required
if(self::$DBConnection){
self::$DBConnection->disconnect();
self::$DBConnection=false;
}
return true;
}
/**
* @brief Escapes bad characters
* @param $string string with dangerous characters
* @returns escaped string
*
* MDB2 escape()
*/
public static function escape( $string ){
self::connect();
return self::$DBConnection->escape( $string );
}
/**
* @brief saves database scheme to xml file
* @param $file name of file
* @returns true/false
*
* TODO: write more documentation
*/
public static function getDbStructure( $file ){
self::connectScheme();
// write the scheme
$definition = self::$schema->getDefinitionFromDatabase();
$dump_options = array(
'output_mode' => 'file',
'output' => $file,
'end_of_line' => "\n"
);
self::$schema->dumpDatabase( $definition, $dump_options, MDB2_SCHEMA_DUMP_STRUCTURE );
return true;
}
/**
* @brief Creates tables from XML file
* @param $file file to read structure from
* @returns true/false
*
* TODO: write more documentation
*/
public static function createDbFromStructure( $file ){
$CONFIG_DBNAME = OC_Config::getValue( "dbname", "owncloud" );
$CONFIG_DBTABLEPREFIX = OC_Config::getValue( "dbtableprefix", "oc_" );
self::connectScheme();
// read file
$content = file_get_contents( $file );
// Make changes and save them to a temporary file
$file2 = tempnam( sys_get_temp_dir(), 'oc_db_scheme_' );
$content = str_replace( '*dbname*', $CONFIG_DBNAME, $content );
$content = str_replace( '*dbprefix*', $CONFIG_DBTABLEPREFIX, $content );
file_put_contents( $file2, $content );
// Try to create tables
$definition = self::$schema->parseDatabaseDefinitionFile( $file2 );
// Delete our temporary file
unlink( $file2 );
// Die in case something went wrong
if( $definition instanceof MDB2_Schema_Error ){
die( $definition->getMessage().': '.$definition->getUserInfo());
}
// if(OC_Config::getValue('dbtype','sqlite')=='sqlite'){
// $definition['overwrite']=true;//always overwrite for sqlite
// }
$ret=self::$schema->createDatabase( $definition );
// Die in case something went wrong
if( $ret instanceof MDB2_Error ){
die ($ret->getMessage() . ': ' . $ret->getUserInfo());
}
return true;
}
/**
* @brief connects to a MDB2 database scheme
* @returns true/false
*
* Connects to a MDB2 database scheme
*/
private static function connectScheme(){
// We need a database connection
self::connect();
// Connect if this did not happen before
if(!self::$schema){
require_once('MDB2/Schema.php');
self::$schema=MDB2_Schema::factory(self::$DBConnection);
}
return true;
}
/**
* @brief does minor chages to query
* @param $query Query string
* @returns corrected query string
*
* This function replaces *PREFIX* with the value of $CONFIG_DBTABLEPREFIX
* and replaces the ` woth ' or " according to the database driver.
*/
private static function processQuery( $query ){
self::connect();
// We need Database type and table prefix
$CONFIG_DBTYPE = OC_Config::getValue( "dbtype", "sqlite" );
$CONFIG_DBTABLEPREFIX = OC_Config::getValue( "dbtableprefix", "oc_" );
// differences is getting the current timestamp
$query = str_replace( 'NOW()', self::$DBConnection->now(), $query );
$query = str_replace( 'now()', self::$DBConnection->now(), $query );
// differences in escaping of table names (` for mysql)
// Problem: what if there is a ` in the value we want to insert?
if( $CONFIG_DBTYPE == 'sqlite' ){
$query = str_replace( '`', '\'', $query );
}
elseif( $CONFIG_DBTYPE == 'pgsql' ){
$query = str_replace( '`', '"', $query );
}
// replace table name prefix
$query = str_replace( '*PREFIX*', $CONFIG_DBTABLEPREFIX, $query );
return $query;
}
/**
* @brief drop a table
* @param string $tableNamme the table to drop
*/
public static function dropTable($tableName){
self::connect();
self::$DBConnection->loadModule('Manager');
self::$DBConnection->dropTable($tableName);
}
/**
* remove all tables defined in a database structure xml file
* @param string $file the xml file describing the tables
*/
public static function removeDBStructure($file){
$CONFIG_DBNAME = OC_Config::getValue( "dbname", "owncloud" );
$CONFIG_DBTABLEPREFIX = OC_Config::getValue( "dbtableprefix", "oc_" );
self::connectScheme();
// read file
$content = file_get_contents( $file );
// Make changes and save them to a temporary file
$file2 = tempnam( sys_get_temp_dir(), 'oc_db_scheme_' );
$content = str_replace( '*dbname*', $CONFIG_DBNAME, $content );
$content = str_replace( '*dbprefix*', $CONFIG_DBTABLEPREFIX, $content );
file_put_contents( $file2, $content );
// get the tables
$definition = self::$schema->parseDatabaseDefinitionFile( $file2 );
// Delete our temporary file
unlink( $file2 );
foreach($definition['tables'] as $name=>$table){
self::dropTable($name);
}
}
/**
* Start a transaction or set a savepoint.
* @param string $savePoint (optional) name of the savepoint to set
*/
public static function beginTransaction($savePoint=''){
self::connect();
if (!self::$DBConnection->supports('transactions')) {
return false;
}
if($savePoint && !self::$DBConnection->supports('savepoints')){
return false;
}
if($savePoint){
self::$DBConnection->beginTransaction($savePoint);
}else{
self::$DBConnection->beginTransaction();
}
}
/**
* Commit the database changes done during a transaction that is in progress or release a savepoint.
* @param string $savePoint (optional) name of the savepoint to commit
*/
public static function commit($savePoint=''){
self::connect();
if(!self::$DBConnection->inTransaction()){
return false;
}
if($savePoint){
self::$DBConnection->commit($savePoint);
}else{
self::$DBConnection->commit();
}
}
}