3 * Helper class for making a copy of the database, mostly for unit testing.
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
18 * http://www.gnu.org/copyleft/gpl.html
23 use MediaWiki\MediaWikiServices
;
24 use Wikimedia\Rdbms\IMaintainableDatabase
;
27 /** @var string Table prefix for cloning */
28 private $newTablePrefix = '';
30 /** @var string Current table prefix */
31 private $oldTablePrefix = '';
33 /** @var array List of tables to be cloned */
34 private $tablesToClone = [];
36 /** @var bool Should we DROP tables containing the new names? */
37 private $dropCurrentTables = true;
39 /** @var bool Whether to use temporary tables or not */
40 private $useTemporaryTables = true;
42 /** @var IMaintainableDatabase */
46 * @param IMaintainableDatabase $db A database subclass
47 * @param array $tablesToClone An array of tables to clone, unprefixed
48 * @param string $newTablePrefix Prefix to assign to the tables
49 * @param string|null $oldTablePrefix Prefix on current tables, if not $wgDBprefix
50 * @param bool $dropCurrentTables
52 public function __construct( IMaintainableDatabase
$db, array $tablesToClone,
53 $newTablePrefix, $oldTablePrefix = null, $dropCurrentTables = true
56 $this->tablesToClone
= $tablesToClone;
57 $this->newTablePrefix
= $newTablePrefix;
58 $this->oldTablePrefix
= $oldTablePrefix ??
$this->db
->tablePrefix();
59 $this->dropCurrentTables
= $dropCurrentTables;
63 * Set whether to use temporary tables or not
64 * @param bool $u Use temporary tables when cloning the structure
66 public function useTemporaryTables( $u = true ) {
67 $this->useTemporaryTables
= $u;
71 * Clone the table structure
73 public function cloneTableStructure() {
74 global $wgSharedTables, $wgSharedDB;
75 foreach ( $this->tablesToClone
as $tbl ) {
76 if ( $wgSharedDB && in_array( $tbl, $wgSharedTables, true ) ) {
77 // Shared tables don't work properly when cloning due to
78 // how prefixes are handled (T67654)
79 throw new RuntimeException( "Cannot clone shared table $tbl." );
81 # Clean up from previous aborted run. So that table escaping
82 # works correctly across DB engines, we need to change the pre-
83 # fix back and forth so tableName() works right.
85 $this->db
->tablePrefix( $this->oldTablePrefix
);
86 $oldTableName = $this->db
->tableName( $tbl, 'raw' );
88 $this->db
->tablePrefix( $this->newTablePrefix
);
89 $newTableName = $this->db
->tableName( $tbl, 'raw' );
91 // Postgres: Temp tables are automatically deleted upon end of session
92 // Same Temp table name hides existing table for current session
93 if ( $this->dropCurrentTables
94 && !in_array( $this->db
->getType(), [ 'oracle' ] )
96 if ( $oldTableName === $newTableName ) {
97 // Last ditch check to avoid data loss
98 throw new LogicException( "Not dropping new table, as '$newTableName'"
99 . " is name of both the old and the new table." );
101 $this->db
->dropTable( $tbl, __METHOD__
);
102 wfDebug( __METHOD__
. " dropping {$newTableName}\n" );
103 // Dropping the oldTable because the prefix was changed
107 wfDebug( __METHOD__
. " duplicating $oldTableName to $newTableName\n" );
108 $this->db
->duplicateTableStructure(
109 $oldTableName, $newTableName, $this->useTemporaryTables
);
114 * Change the prefix back to the original.
115 * @param bool $dropTables Optionally drop the tables we created
117 public function destroy( $dropTables = false ) {
119 $this->db
->tablePrefix( $this->newTablePrefix
);
120 foreach ( $this->tablesToClone
as $tbl ) {
121 $this->db
->dropTable( $tbl );
124 $this->db
->tablePrefix( $this->oldTablePrefix
);
128 * Change the table prefix on all open DB connections/
130 * @param string $prefix
133 public static function changePrefix( $prefix ) {
136 $lbFactory = MediaWikiServices
::getInstance()->getDBLoadBalancerFactory();
137 $lbFactory->setDomainPrefix( $prefix );
138 $wgDBprefix = $prefix;