summaryrefslogtreecommitdiff
path: root/includes/db/CloneDatabase.php
blob: 4e443741bcdaaf22ad89a9a6fcecd16307c6c619 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
<?php
/**
 * Helper class for making a copy of the database, mostly for unit testing.
 *
 * Copyright © 2010 Chad Horohoe <chad@anyonecanedit.org>
 * http://www.mediawiki.org/
 *
 * 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
 */

class CloneDatabase {

	/**
	 * Table prefix for cloning
	 * @var String
	 */
	private $newTablePrefix = '';

	/**
	 * Current table prefix
	 * @var String
	 */
	private $oldTablePrefix = '';

	/**
	 * List of tables to be cloned
	 * @var Array
	 */
	private $tablesToClone = array();

	/**
	 * Should we DROP tables containing the new names?
	 * @var Bool
	 */
	private $dropCurrentTables = true;

	/**
	 * Whether to use temporary tables or not
	 * @var Bool
	 */
	private $useTemporaryTables = true;

	/**
	 * Constructor
	 *
	 * @param $db DatabaseBase A database subclass
	 * @param array $tablesToClone An array of tables to clone, unprefixed
	 * @param string $newTablePrefix Prefix to assign to the tables
	 * @param string $oldTablePrefix Prefix on current tables, if not $wgDBprefix
	 * @param $dropCurrentTables bool
	 */
	public function __construct( DatabaseBase $db, array $tablesToClone,
		$newTablePrefix, $oldTablePrefix = '', $dropCurrentTables = true )
	{
		$this->db = $db;
		$this->tablesToClone = $tablesToClone;
		$this->newTablePrefix = $newTablePrefix;
		$this->oldTablePrefix = $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( $u = true ) {
		$this->useTemporaryTables = $u;
	}

	/**
	 * Clone the table structure
	 */
	public function cloneTableStructure() {
		foreach( $this->tablesToClone as $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.

			self::changePrefix( $this->oldTablePrefix );
			$oldTableName = $this->db->tableName( $tbl, 'raw' );

			self::changePrefix( $this->newTablePrefix );
			$newTableName = $this->db->tableName( $tbl, 'raw' );

			if( $this->dropCurrentTables && !in_array( $this->db->getType(), array( 'postgres', 'oracle' ) ) ) {
				$this->db->dropTable( $tbl, __METHOD__ );
				wfDebug( __METHOD__ . " dropping {$newTableName}\n", true );
				//Dropping the oldTable because the prefix was changed
			}

			# Create new table
			wfDebug( __METHOD__ . " duplicating $oldTableName to $newTableName\n", true );
			$this->db->duplicateTableStructure( $oldTableName, $newTableName, $this->useTemporaryTables );
		}
	}

	/**
	 * Change the prefix back to the original.
	 * @param bool $dropTables Optionally drop the tables we created
	 */
	public function destroy( $dropTables = false ) {
		if( $dropTables ) {
			self::changePrefix( $this->newTablePrefix );
			foreach( $this->tablesToClone as $tbl ) {
				$this->db->dropTable( $tbl );
			}
		}
		self::changePrefix( $this->oldTablePrefix );
	}

	/**
	 * Change the table prefix on all open DB connections/
	 *
	 * @param  $prefix
	 * @return void
	 */
	public static function changePrefix( $prefix ) {
		global $wgDBprefix;
		wfGetLBFactory()->forEachLB( array( 'CloneDatabase', 'changeLBPrefix' ), array( $prefix ) );
		$wgDBprefix = $prefix;
	}

	/**
	 * @param  $lb LoadBalancer
	 * @param  $prefix
	 * @return void
	 */
	public static function changeLBPrefix( $lb, $prefix ) {
		$lb->forEachOpenConnection( array( 'CloneDatabase', 'changeDBPrefix' ), array( $prefix ) );
	}

	/**
	 * @param  $db DatabaseBase
	 * @param  $prefix
	 * @return void
	 */
	public static function changeDBPrefix( $db, $prefix ) {
		$db->tablePrefix( $prefix );
	}
}