3 * Helper class for making a copy of the database, mostly for unit testing.
5 * Copyright © 2010 Chad Horohoe <chad@anyonecanedit.org>
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15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
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20 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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28 /** @var string Table prefix for cloning */
29 private $newTablePrefix = '';
31 /** @var string Current table prefix */
32 private $oldTablePrefix = '';
34 /** @var array List of tables to be cloned */
35 private $tablesToClone = [];
37 /** @var bool Should we DROP tables containing the new names? */
38 private $dropCurrentTables = true;
40 /** @var bool Whether to use temporary tables or not */
41 private $useTemporaryTables = true;
46 * @param DatabaseBase $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 $oldTablePrefix Prefix on current tables, if not $wgDBprefix
50 * @param bool $dropCurrentTables
52 public function __construct( DatabaseBase
$db, array $tablesToClone,
53 $newTablePrefix, $oldTablePrefix = '', $dropCurrentTables = true
56 $this->tablesToClone
= $tablesToClone;
57 $this->newTablePrefix
= $newTablePrefix;
58 $this->oldTablePrefix
= $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 (bug 65654)
79 throw new MWException( "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 self
::changePrefix( $this->oldTablePrefix
);
86 $oldTableName = $this->db
->tableName( $tbl, 'raw' );
88 self
::changePrefix( $this->newTablePrefix
);
89 $newTableName = $this->db
->tableName( $tbl, 'raw' );
91 if ( $this->dropCurrentTables
92 && !in_array( $this->db
->getType(), [ 'postgres', 'oracle' ] )
94 if ( $oldTableName === $newTableName ) {
95 // Last ditch check to avoid data loss
96 throw new MWException( "Not dropping new table, as '$newTableName'"
97 . " is name of both the old and the new table." );
99 $this->db
->dropTable( $tbl, __METHOD__
);
100 wfDebug( __METHOD__
. " dropping {$newTableName}\n" );
101 // Dropping the oldTable because the prefix was changed
105 wfDebug( __METHOD__
. " duplicating $oldTableName to $newTableName\n" );
106 $this->db
->duplicateTableStructure( $oldTableName, $newTableName, $this->useTemporaryTables
);
111 * Change the prefix back to the original.
112 * @param bool $dropTables Optionally drop the tables we created
114 public function destroy( $dropTables = false ) {
116 self
::changePrefix( $this->newTablePrefix
);
117 foreach ( $this->tablesToClone
as $tbl ) {
118 $this->db
->dropTable( $tbl );
121 self
::changePrefix( $this->oldTablePrefix
);
125 * Change the table prefix on all open DB connections/
127 * @param string $prefix
130 public static function changePrefix( $prefix ) {
132 wfGetLBFactory()->forEachLB( [ 'CloneDatabase', 'changeLBPrefix' ], [ $prefix ] );
133 $wgDBprefix = $prefix;
137 * @param LoadBalancer $lb
138 * @param string $prefix
141 public static function changeLBPrefix( $lb, $prefix ) {
142 $lb->forEachOpenConnection( [ 'CloneDatabase', 'changeDBPrefix' ], [ $prefix ] );
146 * @param DatabaseBase $db
147 * @param string $prefix
150 public static function changeDBPrefix( $db, $prefix ) {
151 $db->tablePrefix( $prefix );