wiki.techinc.nl/includes/db/CloneDatabase.php
2024-10-17 23:38:11 +00:00

148 lines
4.8 KiB
PHP

<?php
/**
* Helper class for making a copy of the database, mostly for unit testing.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*
* @file
* @ingroup Database
*/
use MediaWiki\MediaWikiServices;
use Wikimedia\Rdbms\IMaintainableDatabase;
class CloneDatabase {
/** Table prefix for cloning */
private string $newTablePrefix;
/** Current table prefix */
private string $oldTablePrefix;
/** List of tables to be cloned */
private array $tablesToClone;
/** Should we DROP tables containing the new names? */
private bool $dropCurrentTables;
/** Whether to use temporary tables or not */
private bool $useTemporaryTables = true;
private IMaintainableDatabase $db;
/**
* @param IMaintainableDatabase $db A database subclass
* @param array $tablesToClone An array of tables to clone, unprefixed
* @param string $newTablePrefix Prefix to assign to the tables
* @param string|null $oldTablePrefix Prefix on current tables, if not $wgDBprefix
* @param bool $dropCurrentTables
*/
public function __construct(
IMaintainableDatabase $db,
array $tablesToClone,
string $newTablePrefix,
?string $oldTablePrefix = null,
bool $dropCurrentTables = true
) {
if ( !$tablesToClone ) {
throw new InvalidArgumentException( 'Empty list of tables to clone' );
}
$this->db = $db;
$this->tablesToClone = $tablesToClone;
$this->newTablePrefix = $newTablePrefix;
$this->oldTablePrefix = $oldTablePrefix ?? $this->db->tablePrefix();
$this->dropCurrentTables = $dropCurrentTables;
}
/**
* Set whether to use temporary tables or not
* @param bool $u Use temporary tables when cloning the structure
*/
public function useTemporaryTables( bool $u = true ): void {
$this->useTemporaryTables = $u;
}
public function cloneTableStructure(): void {
global $wgSharedTables, $wgSharedDB;
foreach ( $this->tablesToClone as $tbl ) {
if ( $wgSharedDB && in_array( $tbl, $wgSharedTables, true ) ) {
// Shared tables don't work properly when cloning due to
// how prefixes are handled (T67654)
throw new RuntimeException( "Cannot clone shared table $tbl." );
}
# Clean up from previous aborted run. So that table escaping
# works correctly across DB engines, we need to change the pre-
# fix back and forth so tableName() works right.
$this->db->tablePrefix( $this->oldTablePrefix );
$oldTableName = $this->db->tableName( $tbl, 'raw' );
$this->db->tablePrefix( $this->newTablePrefix );
$newTableName = $this->db->tableName( $tbl, 'raw' );
// Postgres: Temp tables are automatically deleted upon end of session
// Same Temp table name hides existing table for current session
if ( $this->dropCurrentTables ) {
if ( $oldTableName === $newTableName ) {
// Last ditch check to avoid data loss
throw new LogicException( "Not dropping new table, as '$newTableName'"
. " is name of both the old and the new table." );
}
$this->db->dropTable( $tbl, __METHOD__ );
// Dropping the oldTable because the prefix was changed
}
# Create new table
$this->db->duplicateTableStructure(
$oldTableName, $newTableName, $this->useTemporaryTables, __METHOD__ );
}
}
/**
* Change the prefix back to the original.
* @param bool $dropTables Optionally drop the tables we created
*/
public function destroy( bool $dropTables = false ): void {
if ( $dropTables ) {
$this->db->tablePrefix( $this->newTablePrefix );
foreach ( $this->tablesToClone as $tbl ) {
$this->db->dropTable( $tbl, __METHOD__ );
}
}
$this->db->tablePrefix( $this->oldTablePrefix );
}
/**
* Change the table prefix on all open DB connections
*
* @param string $prefix
* @return void
*/
public static function changePrefix( string $prefix ): void {
global $wgDBprefix, $wgDBname;
$lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
$lbFactory->setLocalDomainPrefix( $prefix );
$aliases = [
$wgDBname => $lbFactory->getLocalDomainID()
];
$lbFactory->setDomainAliases( $aliases );
foreach ( $lbFactory->getAllLBs() as $lb ) {
$lb->setDomainAliases( $aliases );
}
$wgDBprefix = $prefix;
}
}