Merge "rdbms: Use correct value for 'sslmode' in DatabasePostgres"
[lhc/web/wiklou.git] / includes / libs / rdbms / database / DatabasePostgres.php
1 <?php
2 /**
3 * This is the Postgres database abstraction layer.
4 *
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.
9 *
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.
14 *
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
19 *
20 * @file
21 * @ingroup Database
22 */
23 namespace Wikimedia\Rdbms;
24
25 use Wikimedia\Timestamp\ConvertibleTimestamp;
26 use Wikimedia\WaitConditionLoop;
27 use Wikimedia;
28 use Exception;
29
30 /**
31 * @ingroup Database
32 */
33 class DatabasePostgres extends Database {
34 /** @var int|bool */
35 protected $port;
36
37 /** @var resource */
38 protected $lastResultHandle = null;
39
40 /** @var float|string */
41 private $numericVersion = null;
42 /** @var string Connect string to open a PostgreSQL connection */
43 private $connectString;
44 /** @var string */
45 private $coreSchema;
46 /** @var string */
47 private $tempSchema;
48 /** @var string[] Map of (reserved table name => alternate table name) */
49 private $keywordTableMap = [];
50
51 /**
52 * @see Database::__construct()
53 * @param array $params Additional parameters include:
54 * - keywordTableMap : Map of reserved table names to alternative table names to use
55 */
56 public function __construct( array $params ) {
57 $this->port = $params['port'] ?? false;
58 $this->keywordTableMap = $params['keywordTableMap'] ?? [];
59
60 parent::__construct( $params );
61 }
62
63 public function getType() {
64 return 'postgres';
65 }
66
67 public function implicitGroupby() {
68 return false;
69 }
70
71 public function implicitOrderby() {
72 return false;
73 }
74
75 public function hasConstraint( $name ) {
76 foreach ( $this->getCoreSchemas() as $schema ) {
77 $sql = "SELECT 1 FROM pg_catalog.pg_constraint c, pg_catalog.pg_namespace n " .
78 "WHERE c.connamespace = n.oid AND conname = " .
79 $this->addQuotes( $name ) . " AND n.nspname = " .
80 $this->addQuotes( $schema );
81 $res = $this->doQuery( $sql );
82 if ( $res && $this->numRows( $res ) ) {
83 return true;
84 }
85 }
86 return false;
87 }
88
89 protected function open( $server, $user, $password, $dbName, $schema, $tablePrefix ) {
90 # Test for Postgres support, to avoid suppressed fatal error
91 if ( !function_exists( 'pg_connect' ) ) {
92 throw new DBConnectionError(
93 $this,
94 "Postgres functions missing, have you compiled PHP with the --with-pgsql\n" .
95 "option? (Note: if you recently installed PHP, you may need to restart your\n" .
96 "webserver and database)\n"
97 );
98 }
99
100 $this->server = $server;
101 $this->user = $user;
102 $this->password = $password;
103
104 $connectVars = [
105 // pg_connect() user $user as the default database. Since a database is *required*,
106 // at least pick a "don't care" database that is more likely to exist. This case
107 // arrises when LoadBalancer::getConnection( $i, [], '' ) is used.
108 'dbname' => strlen( $dbName ) ? $dbName : 'postgres',
109 'user' => $user,
110 'password' => $password
111 ];
112 if ( $server != false && $server != '' ) {
113 $connectVars['host'] = $server;
114 }
115 if ( (int)$this->port > 0 ) {
116 $connectVars['port'] = (int)$this->port;
117 }
118 if ( $this->flags & self::DBO_SSL ) {
119 $connectVars['sslmode'] = 'require';
120 }
121
122 $this->connectString = $this->makeConnectionString( $connectVars );
123 $this->close();
124 $this->installErrorHandler();
125
126 try {
127 // Use new connections to let LoadBalancer/LBFactory handle reuse
128 $this->conn = pg_connect( $this->connectString, PGSQL_CONNECT_FORCE_NEW );
129 } catch ( Exception $ex ) {
130 $this->restoreErrorHandler();
131 throw $ex;
132 }
133
134 $phpError = $this->restoreErrorHandler();
135
136 if ( !$this->conn ) {
137 $this->queryLogger->debug(
138 "DB connection error\n" .
139 "Server: $server, Database: $dbName, User: $user, Password: " .
140 substr( $password, 0, 3 ) . "...\n"
141 );
142 $this->queryLogger->debug( $this->lastError() . "\n" );
143 throw new DBConnectionError( $this, str_replace( "\n", ' ', $phpError ) );
144 }
145
146 $this->opened = true;
147
148 # If called from the command-line (e.g. importDump), only show errors
149 if ( $this->cliMode ) {
150 $this->doQuery( "SET client_min_messages = 'ERROR'" );
151 }
152
153 $this->query( "SET client_encoding='UTF8'", __METHOD__ );
154 $this->query( "SET datestyle = 'ISO, YMD'", __METHOD__ );
155 $this->query( "SET timezone = 'GMT'", __METHOD__ );
156 $this->query( "SET standard_conforming_strings = on", __METHOD__ );
157 $this->query( "SET bytea_output = 'escape'", __METHOD__ ); // PHP bug 53127
158
159 $this->determineCoreSchema( $schema );
160 $this->currentDomain = new DatabaseDomain( $dbName, $schema, $tablePrefix );
161
162 return (bool)$this->conn;
163 }
164
165 protected function relationSchemaQualifier() {
166 if ( $this->coreSchema === $this->currentDomain->getSchema() ) {
167 // The schema to be used is now in the search path; no need for explicit qualification
168 return '';
169 }
170
171 return parent::relationSchemaQualifier();
172 }
173
174 public function databasesAreIndependent() {
175 return true;
176 }
177
178 public function doSelectDomain( DatabaseDomain $domain ) {
179 if ( $this->getDBname() !== $domain->getDatabase() ) {
180 // Postgres doesn't support selectDB in the same way MySQL does.
181 // So if the DB name doesn't match the open connection, open a new one
182 $this->open(
183 $this->server,
184 $this->user,
185 $this->password,
186 $domain->getDatabase(),
187 $domain->getSchema(),
188 $domain->getTablePrefix()
189 );
190 } else {
191 $this->currentDomain = $domain;
192 }
193
194 return true;
195 }
196
197 /**
198 * @param string[] $vars
199 * @return string
200 */
201 private function makeConnectionString( $vars ) {
202 $s = '';
203 foreach ( $vars as $name => $value ) {
204 $s .= "$name='" . str_replace( "'", "\\'", $value ) . "' ";
205 }
206
207 return $s;
208 }
209
210 protected function closeConnection() {
211 return $this->conn ? pg_close( $this->conn ) : true;
212 }
213
214 protected function isTransactableQuery( $sql ) {
215 return parent::isTransactableQuery( $sql ) &&
216 !preg_match( '/^SELECT\s+pg_(try_|)advisory_\w+\(/', $sql );
217 }
218
219 /**
220 * @param string $sql
221 * @return bool|mixed|resource
222 */
223 public function doQuery( $sql ) {
224 $conn = $this->getBindingHandle();
225
226 $sql = mb_convert_encoding( $sql, 'UTF-8' );
227 // Clear previously left over PQresult
228 while ( $res = pg_get_result( $conn ) ) {
229 pg_free_result( $res );
230 }
231 if ( pg_send_query( $conn, $sql ) === false ) {
232 throw new DBUnexpectedError( $this, "Unable to post new query to PostgreSQL\n" );
233 }
234 $this->lastResultHandle = pg_get_result( $conn );
235 if ( pg_result_error( $this->lastResultHandle ) ) {
236 return false;
237 }
238
239 return $this->lastResultHandle;
240 }
241
242 protected function dumpError() {
243 $diags = [
244 PGSQL_DIAG_SEVERITY,
245 PGSQL_DIAG_SQLSTATE,
246 PGSQL_DIAG_MESSAGE_PRIMARY,
247 PGSQL_DIAG_MESSAGE_DETAIL,
248 PGSQL_DIAG_MESSAGE_HINT,
249 PGSQL_DIAG_STATEMENT_POSITION,
250 PGSQL_DIAG_INTERNAL_POSITION,
251 PGSQL_DIAG_INTERNAL_QUERY,
252 PGSQL_DIAG_CONTEXT,
253 PGSQL_DIAG_SOURCE_FILE,
254 PGSQL_DIAG_SOURCE_LINE,
255 PGSQL_DIAG_SOURCE_FUNCTION
256 ];
257 foreach ( $diags as $d ) {
258 $this->queryLogger->debug( sprintf( "PgSQL ERROR(%d): %s\n",
259 $d, pg_result_error_field( $this->lastResultHandle, $d ) ) );
260 }
261 }
262
263 public function freeResult( $res ) {
264 if ( $res instanceof ResultWrapper ) {
265 $res = $res->result;
266 }
267 Wikimedia\suppressWarnings();
268 $ok = pg_free_result( $res );
269 Wikimedia\restoreWarnings();
270 if ( !$ok ) {
271 throw new DBUnexpectedError( $this, "Unable to free Postgres result\n" );
272 }
273 }
274
275 public function fetchObject( $res ) {
276 if ( $res instanceof ResultWrapper ) {
277 $res = $res->result;
278 }
279 Wikimedia\suppressWarnings();
280 $row = pg_fetch_object( $res );
281 Wikimedia\restoreWarnings();
282 # @todo FIXME: HACK HACK HACK HACK debug
283
284 # @todo hashar: not sure if the following test really trigger if the object
285 # fetching failed.
286 $conn = $this->getBindingHandle();
287 if ( pg_last_error( $conn ) ) {
288 throw new DBUnexpectedError(
289 $this,
290 'SQL error: ' . htmlspecialchars( pg_last_error( $conn ) )
291 );
292 }
293
294 return $row;
295 }
296
297 public function fetchRow( $res ) {
298 if ( $res instanceof ResultWrapper ) {
299 $res = $res->result;
300 }
301 Wikimedia\suppressWarnings();
302 $row = pg_fetch_array( $res );
303 Wikimedia\restoreWarnings();
304
305 $conn = $this->getBindingHandle();
306 if ( pg_last_error( $conn ) ) {
307 throw new DBUnexpectedError(
308 $this,
309 'SQL error: ' . htmlspecialchars( pg_last_error( $conn ) )
310 );
311 }
312
313 return $row;
314 }
315
316 public function numRows( $res ) {
317 if ( $res === false ) {
318 return 0;
319 }
320
321 if ( $res instanceof ResultWrapper ) {
322 $res = $res->result;
323 }
324 Wikimedia\suppressWarnings();
325 $n = pg_num_rows( $res );
326 Wikimedia\restoreWarnings();
327
328 $conn = $this->getBindingHandle();
329 if ( pg_last_error( $conn ) ) {
330 throw new DBUnexpectedError(
331 $this,
332 'SQL error: ' . htmlspecialchars( pg_last_error( $conn ) )
333 );
334 }
335
336 return $n;
337 }
338
339 public function numFields( $res ) {
340 if ( $res instanceof ResultWrapper ) {
341 $res = $res->result;
342 }
343
344 return pg_num_fields( $res );
345 }
346
347 public function fieldName( $res, $n ) {
348 if ( $res instanceof ResultWrapper ) {
349 $res = $res->result;
350 }
351
352 return pg_field_name( $res, $n );
353 }
354
355 public function insertId() {
356 $res = $this->query( "SELECT lastval()" );
357 $row = $this->fetchRow( $res );
358 return is_null( $row[0] ) ? null : (int)$row[0];
359 }
360
361 public function dataSeek( $res, $row ) {
362 if ( $res instanceof ResultWrapper ) {
363 $res = $res->result;
364 }
365
366 return pg_result_seek( $res, $row );
367 }
368
369 public function lastError() {
370 if ( $this->conn ) {
371 if ( $this->lastResultHandle ) {
372 return pg_result_error( $this->lastResultHandle );
373 } else {
374 return pg_last_error();
375 }
376 }
377
378 return $this->getLastPHPError() ?: 'No database connection';
379 }
380
381 public function lastErrno() {
382 if ( $this->lastResultHandle ) {
383 return pg_result_error_field( $this->lastResultHandle, PGSQL_DIAG_SQLSTATE );
384 } else {
385 return false;
386 }
387 }
388
389 protected function fetchAffectedRowCount() {
390 if ( !$this->lastResultHandle ) {
391 return 0;
392 }
393
394 return pg_affected_rows( $this->lastResultHandle );
395 }
396
397 /**
398 * Estimate rows in dataset
399 * Returns estimated count, based on EXPLAIN output
400 * This is not necessarily an accurate estimate, so use sparingly
401 * Returns -1 if count cannot be found
402 * Takes same arguments as Database::select()
403 *
404 * @param string $table
405 * @param string $var
406 * @param string $conds
407 * @param string $fname
408 * @param array $options
409 * @param array $join_conds
410 * @return int
411 */
412 public function estimateRowCount( $table, $var = '*', $conds = '',
413 $fname = __METHOD__, $options = [], $join_conds = []
414 ) {
415 $conds = $this->normalizeConditions( $conds, $fname );
416 $column = $this->extractSingleFieldFromList( $var );
417 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
418 $conds[] = "$column IS NOT NULL";
419 }
420
421 $options['EXPLAIN'] = true;
422 $res = $this->select( $table, $var, $conds, $fname, $options, $join_conds );
423 $rows = -1;
424 if ( $res ) {
425 $row = $this->fetchRow( $res );
426 $count = [];
427 if ( preg_match( '/rows=(\d+)/', $row[0], $count ) ) {
428 $rows = (int)$count[1];
429 }
430 }
431
432 return $rows;
433 }
434
435 public function indexInfo( $table, $index, $fname = __METHOD__ ) {
436 $sql = "SELECT indexname FROM pg_indexes WHERE tablename='$table'";
437 $res = $this->query( $sql, $fname );
438 if ( !$res ) {
439 return null;
440 }
441 foreach ( $res as $row ) {
442 if ( $row->indexname == $this->indexName( $index ) ) {
443 return $row;
444 }
445 }
446
447 return false;
448 }
449
450 public function indexAttributes( $index, $schema = false ) {
451 if ( $schema === false ) {
452 $schemas = $this->getCoreSchemas();
453 } else {
454 $schemas = [ $schema ];
455 }
456
457 $eindex = $this->addQuotes( $index );
458
459 foreach ( $schemas as $schema ) {
460 $eschema = $this->addQuotes( $schema );
461 /*
462 * A subquery would be not needed if we didn't care about the order
463 * of attributes, but we do
464 */
465 $sql = <<<__INDEXATTR__
466
467 SELECT opcname,
468 attname,
469 i.indoption[s.g] as option,
470 pg_am.amname
471 FROM
472 (SELECT generate_series(array_lower(isub.indkey,1), array_upper(isub.indkey,1)) AS g
473 FROM
474 pg_index isub
475 JOIN pg_class cis
476 ON cis.oid=isub.indexrelid
477 JOIN pg_namespace ns
478 ON cis.relnamespace = ns.oid
479 WHERE cis.relname=$eindex AND ns.nspname=$eschema) AS s,
480 pg_attribute,
481 pg_opclass opcls,
482 pg_am,
483 pg_class ci
484 JOIN pg_index i
485 ON ci.oid=i.indexrelid
486 JOIN pg_class ct
487 ON ct.oid = i.indrelid
488 JOIN pg_namespace n
489 ON ci.relnamespace = n.oid
490 WHERE
491 ci.relname=$eindex AND n.nspname=$eschema
492 AND attrelid = ct.oid
493 AND i.indkey[s.g] = attnum
494 AND i.indclass[s.g] = opcls.oid
495 AND pg_am.oid = opcls.opcmethod
496 __INDEXATTR__;
497 $res = $this->query( $sql, __METHOD__ );
498 $a = [];
499 if ( $res ) {
500 foreach ( $res as $row ) {
501 $a[] = [
502 $row->attname,
503 $row->opcname,
504 $row->amname,
505 $row->option ];
506 }
507 return $a;
508 }
509 }
510 return null;
511 }
512
513 public function indexUnique( $table, $index, $fname = __METHOD__ ) {
514 $sql = "SELECT indexname FROM pg_indexes WHERE tablename='{$table}'" .
515 " AND indexdef LIKE 'CREATE UNIQUE%(" .
516 $this->strencode( $this->indexName( $index ) ) .
517 ")'";
518 $res = $this->query( $sql, $fname );
519 if ( !$res ) {
520 return null;
521 }
522
523 return $res->numRows() > 0;
524 }
525
526 public function selectSQLText(
527 $table, $vars, $conds = '', $fname = __METHOD__, $options = [], $join_conds = []
528 ) {
529 if ( is_string( $options ) ) {
530 $options = [ $options ];
531 }
532
533 // Change the FOR UPDATE option as necessary based on the join conditions. Then pass
534 // to the parent function to get the actual SQL text.
535 // In Postgres when using FOR UPDATE, only the main table and tables that are inner joined
536 // can be locked. That means tables in an outer join cannot be FOR UPDATE locked. Trying to
537 // do so causes a DB error. This wrapper checks which tables can be locked and adjusts it
538 // accordingly.
539 // MySQL uses "ORDER BY NULL" as an optimization hint, but that is illegal in PostgreSQL.
540 if ( is_array( $options ) ) {
541 $forUpdateKey = array_search( 'FOR UPDATE', $options, true );
542 if ( $forUpdateKey !== false && $join_conds ) {
543 unset( $options[$forUpdateKey] );
544 $options['FOR UPDATE'] = [];
545
546 $toCheck = $table;
547 reset( $toCheck );
548 while ( $toCheck ) {
549 $alias = key( $toCheck );
550 $name = $toCheck[$alias];
551 unset( $toCheck[$alias] );
552
553 $hasAlias = !is_numeric( $alias );
554 if ( !$hasAlias && is_string( $name ) ) {
555 $alias = $name;
556 }
557
558 if ( !isset( $join_conds[$alias] ) ||
559 !preg_match( '/^(?:LEFT|RIGHT|FULL)(?: OUTER)? JOIN$/i', $join_conds[$alias][0] )
560 ) {
561 if ( is_array( $name ) ) {
562 // It's a parenthesized group, process all the tables inside the group.
563 $toCheck = array_merge( $toCheck, $name );
564 } else {
565 // Quote alias names so $this->tableName() won't mangle them
566 $options['FOR UPDATE'][] = $hasAlias ? $this->addIdentifierQuotes( $alias ) : $alias;
567 }
568 }
569 }
570 }
571
572 if ( isset( $options['ORDER BY'] ) && $options['ORDER BY'] == 'NULL' ) {
573 unset( $options['ORDER BY'] );
574 }
575 }
576
577 return parent::selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds );
578 }
579
580 /** @inheritDoc */
581 public function insert( $table, $args, $fname = __METHOD__, $options = [] ) {
582 if ( !count( $args ) ) {
583 return true;
584 }
585
586 $table = $this->tableName( $table );
587 if ( !isset( $this->numericVersion ) ) {
588 $this->getServerVersion();
589 }
590
591 if ( !is_array( $options ) ) {
592 $options = [ $options ];
593 }
594
595 if ( isset( $args[0] ) && is_array( $args[0] ) ) {
596 $rows = $args;
597 $keys = array_keys( $args[0] );
598 } else {
599 $rows = [ $args ];
600 $keys = array_keys( $args );
601 }
602
603 $ignore = in_array( 'IGNORE', $options );
604
605 $sql = "INSERT INTO $table (" . implode( ',', $keys ) . ') VALUES ';
606
607 if ( $this->numericVersion >= 9.5 || !$ignore ) {
608 // No IGNORE or our PG has "ON CONFLICT DO NOTHING"
609 $first = true;
610 foreach ( $rows as $row ) {
611 if ( $first ) {
612 $first = false;
613 } else {
614 $sql .= ',';
615 }
616 $sql .= '(' . $this->makeList( $row ) . ')';
617 }
618 if ( $ignore ) {
619 $sql .= ' ON CONFLICT DO NOTHING';
620 }
621 $this->query( $sql, $fname );
622 } else {
623 // Emulate IGNORE by doing each row individually, with savepoints
624 // to roll back as necessary.
625 $numrowsinserted = 0;
626
627 $tok = $this->startAtomic( "$fname (outer)", self::ATOMIC_CANCELABLE );
628 try {
629 foreach ( $rows as $row ) {
630 $tempsql = $sql;
631 $tempsql .= '(' . $this->makeList( $row ) . ')';
632
633 $this->startAtomic( "$fname (inner)", self::ATOMIC_CANCELABLE );
634 try {
635 $this->query( $tempsql, $fname );
636 $this->endAtomic( "$fname (inner)" );
637 $numrowsinserted++;
638 } catch ( DBQueryError $e ) {
639 $this->cancelAtomic( "$fname (inner)" );
640 // Our IGNORE is supposed to ignore duplicate key errors, but not others.
641 // (even though MySQL's version apparently ignores all errors)
642 if ( $e->errno !== '23505' ) {
643 throw $e;
644 }
645 }
646 }
647 } catch ( Exception $e ) {
648 $this->cancelAtomic( "$fname (outer)", $tok );
649 throw $e;
650 }
651 $this->endAtomic( "$fname (outer)" );
652
653 // Set the affected row count for the whole operation
654 $this->affectedRowCount = $numrowsinserted;
655 }
656
657 return true;
658 }
659
660 protected function makeUpdateOptionsArray( $options ) {
661 if ( !is_array( $options ) ) {
662 $options = [ $options ];
663 }
664
665 // PostgreSQL doesn't support anything like "ignore" for
666 // UPDATE.
667 $options = array_diff( $options, [ 'IGNORE' ] );
668
669 return parent::makeUpdateOptionsArray( $options );
670 }
671
672 /**
673 * INSERT SELECT wrapper
674 * $varMap must be an associative array of the form [ 'dest1' => 'source1', ... ]
675 * Source items may be literals rather then field names, but strings should
676 * be quoted with Database::addQuotes()
677 * $conds may be "*" to copy the whole table
678 * srcTable may be an array of tables.
679 * @todo FIXME: Implement this a little better (separate select/insert)?
680 *
681 * @param string $destTable
682 * @param array|string $srcTable
683 * @param array $varMap
684 * @param array $conds
685 * @param string $fname
686 * @param array $insertOptions
687 * @param array $selectOptions
688 * @param array $selectJoinConds
689 */
690 protected function nativeInsertSelect(
691 $destTable, $srcTable, $varMap, $conds, $fname = __METHOD__,
692 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
693 ) {
694 if ( !is_array( $insertOptions ) ) {
695 $insertOptions = [ $insertOptions ];
696 }
697
698 if ( in_array( 'IGNORE', $insertOptions ) ) {
699 if ( $this->getServerVersion() >= 9.5 ) {
700 // Use ON CONFLICT DO NOTHING if we have it for IGNORE
701 $destTable = $this->tableName( $destTable );
702
703 $selectSql = $this->selectSQLText(
704 $srcTable,
705 array_values( $varMap ),
706 $conds,
707 $fname,
708 $selectOptions,
709 $selectJoinConds
710 );
711
712 $sql = "INSERT INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ') ' .
713 $selectSql . ' ON CONFLICT DO NOTHING';
714
715 $this->query( $sql, $fname );
716 } else {
717 // IGNORE and we don't have ON CONFLICT DO NOTHING, so just use the non-native version
718 $this->nonNativeInsertSelect(
719 $destTable, $srcTable, $varMap, $conds, $fname,
720 $insertOptions, $selectOptions, $selectJoinConds
721 );
722 }
723 } else {
724 parent::nativeInsertSelect( $destTable, $srcTable, $varMap, $conds, $fname,
725 $insertOptions, $selectOptions, $selectJoinConds );
726 }
727 }
728
729 public function tableName( $name, $format = 'quoted' ) {
730 // Replace reserved words with better ones
731 $name = $this->remappedTableName( $name );
732
733 return parent::tableName( $name, $format );
734 }
735
736 /**
737 * @param string $name
738 * @return string Value of $name or remapped name if $name is a reserved keyword
739 */
740 public function remappedTableName( $name ) {
741 return $this->keywordTableMap[$name] ?? $name;
742 }
743
744 /**
745 * @param string $name
746 * @param string $format
747 * @return string Qualified and encoded (if requested) table name
748 */
749 public function realTableName( $name, $format = 'quoted' ) {
750 return parent::tableName( $name, $format );
751 }
752
753 public function nextSequenceValue( $seqName ) {
754 return new NextSequenceValue;
755 }
756
757 /**
758 * Return the current value of a sequence. Assumes it has been nextval'ed in this session.
759 *
760 * @param string $seqName
761 * @return int
762 */
763 public function currentSequenceValue( $seqName ) {
764 $safeseq = str_replace( "'", "''", $seqName );
765 $res = $this->query( "SELECT currval('$safeseq')" );
766 $row = $this->fetchRow( $res );
767 $currval = $row[0];
768
769 return $currval;
770 }
771
772 public function textFieldSize( $table, $field ) {
773 $table = $this->tableName( $table );
774 $sql = "SELECT t.typname as ftype,a.atttypmod as size
775 FROM pg_class c, pg_attribute a, pg_type t
776 WHERE relname='$table' AND a.attrelid=c.oid AND
777 a.atttypid=t.oid and a.attname='$field'";
778 $res = $this->query( $sql );
779 $row = $this->fetchObject( $res );
780 if ( $row->ftype == 'varchar' ) {
781 $size = $row->size - 4;
782 } else {
783 $size = $row->size;
784 }
785
786 return $size;
787 }
788
789 public function limitResult( $sql, $limit, $offset = false ) {
790 return "$sql LIMIT $limit " . ( is_numeric( $offset ) ? " OFFSET {$offset} " : '' );
791 }
792
793 public function wasDeadlock() {
794 // https://www.postgresql.org/docs/9.2/static/errcodes-appendix.html
795 return $this->lastErrno() === '40P01';
796 }
797
798 public function wasLockTimeout() {
799 // https://www.postgresql.org/docs/9.2/static/errcodes-appendix.html
800 return $this->lastErrno() === '55P03';
801 }
802
803 public function wasConnectionError( $errno ) {
804 // https://www.postgresql.org/docs/9.2/static/errcodes-appendix.html
805 static $codes = [ '08000', '08003', '08006', '08001', '08004', '57P01', '57P03', '53300' ];
806
807 return in_array( $errno, $codes, true );
808 }
809
810 protected function wasKnownStatementRollbackError() {
811 return false; // transaction has to be rolled-back from error state
812 }
813
814 public function duplicateTableStructure(
815 $oldName, $newName, $temporary = false, $fname = __METHOD__
816 ) {
817 $newNameE = $this->addIdentifierQuotes( $newName );
818 $oldNameE = $this->addIdentifierQuotes( $oldName );
819
820 $temporary = $temporary ? 'TEMPORARY' : '';
821
822 $ret = $this->query( "CREATE $temporary TABLE $newNameE " .
823 "(LIKE $oldNameE INCLUDING DEFAULTS INCLUDING INDEXES)", $fname );
824 if ( !$ret ) {
825 return $ret;
826 }
827
828 $res = $this->query( 'SELECT attname FROM pg_class c'
829 . ' JOIN pg_namespace n ON (n.oid = c.relnamespace)'
830 . ' JOIN pg_attribute a ON (a.attrelid = c.oid)'
831 . ' JOIN pg_attrdef d ON (c.oid=d.adrelid and a.attnum=d.adnum)'
832 . ' WHERE relkind = \'r\''
833 . ' AND nspname = ' . $this->addQuotes( $this->getCoreSchema() )
834 . ' AND relname = ' . $this->addQuotes( $oldName )
835 . ' AND pg_get_expr(adbin, adrelid) LIKE \'nextval(%\'',
836 $fname
837 );
838 $row = $this->fetchObject( $res );
839 if ( $row ) {
840 $field = $row->attname;
841 $newSeq = "{$newName}_{$field}_seq";
842 $fieldE = $this->addIdentifierQuotes( $field );
843 $newSeqE = $this->addIdentifierQuotes( $newSeq );
844 $newSeqQ = $this->addQuotes( $newSeq );
845 $this->query( "CREATE $temporary SEQUENCE $newSeqE OWNED BY $newNameE.$fieldE", $fname );
846 $this->query(
847 "ALTER TABLE $newNameE ALTER COLUMN $fieldE SET DEFAULT nextval({$newSeqQ}::regclass)",
848 $fname
849 );
850 }
851
852 return $ret;
853 }
854
855 public function resetSequenceForTable( $table, $fname = __METHOD__ ) {
856 $table = $this->tableName( $table, 'raw' );
857 foreach ( $this->getCoreSchemas() as $schema ) {
858 $res = $this->query(
859 'SELECT c.oid FROM pg_class c JOIN pg_namespace n ON (n.oid = c.relnamespace)'
860 . ' WHERE relkind = \'r\''
861 . ' AND nspname = ' . $this->addQuotes( $schema )
862 . ' AND relname = ' . $this->addQuotes( $table ),
863 $fname
864 );
865 if ( !$res || !$this->numRows( $res ) ) {
866 continue;
867 }
868
869 $oid = $this->fetchObject( $res )->oid;
870 $res = $this->query( 'SELECT pg_get_expr(adbin, adrelid) AS adsrc FROM pg_attribute a'
871 . ' JOIN pg_attrdef d ON (a.attrelid=d.adrelid and a.attnum=d.adnum)'
872 . " WHERE a.attrelid = $oid"
873 . ' AND pg_get_expr(adbin, adrelid) LIKE \'nextval(%\'',
874 $fname
875 );
876 $row = $this->fetchObject( $res );
877 if ( $row ) {
878 $this->query(
879 'SELECT ' . preg_replace( '/^nextval\((.+)\)$/', 'setval($1,1,false)', $row->adsrc ),
880 $fname
881 );
882 return true;
883 }
884 return false;
885 }
886
887 return false;
888 }
889
890 /**
891 * @suppress SecurityCheck-SQLInjection array_map not recognized T204911
892 */
893 public function listTables( $prefix = null, $fname = __METHOD__ ) {
894 $eschemas = implode( ',', array_map( [ $this, 'addQuotes' ], $this->getCoreSchemas() ) );
895 $result = $this->query(
896 "SELECT DISTINCT tablename FROM pg_tables WHERE schemaname IN ($eschemas)", $fname );
897 $endArray = [];
898
899 foreach ( $result as $table ) {
900 $vars = get_object_vars( $table );
901 $table = array_pop( $vars );
902 if ( !$prefix || strpos( $table, $prefix ) === 0 ) {
903 $endArray[] = $table;
904 }
905 }
906
907 return $endArray;
908 }
909
910 public function timestamp( $ts = 0 ) {
911 $ct = new ConvertibleTimestamp( $ts );
912
913 return $ct->getTimestamp( TS_POSTGRES );
914 }
915
916 /**
917 * Posted by cc[plus]php[at]c2se[dot]com on 25-Mar-2009 09:12
918 * to https://secure.php.net/manual/en/ref.pgsql.php
919 *
920 * Parsing a postgres array can be a tricky problem, he's my
921 * take on this, it handles multi-dimensional arrays plus
922 * escaping using a nasty regexp to determine the limits of each
923 * data-item.
924 *
925 * This should really be handled by PHP PostgreSQL module
926 *
927 * @since 1.19
928 * @param string $text Postgreql array returned in a text form like {a,b}
929 * @param string[] $output
930 * @param int|bool $limit
931 * @param int $offset
932 * @return string[]
933 */
934 private function pg_array_parse( $text, &$output, $limit = false, $offset = 1 ) {
935 if ( $limit === false ) {
936 $limit = strlen( $text ) - 1;
937 $output = [];
938 }
939 if ( $text == '{}' ) {
940 return $output;
941 }
942 do {
943 if ( $text[$offset] != '{' ) {
944 preg_match( "/(\\{?\"([^\"\\\\]|\\\\.)*\"|[^,{}]+)+([,}]+)/",
945 $text, $match, 0, $offset );
946 $offset += strlen( $match[0] );
947 $output[] = ( $match[1][0] != '"'
948 ? $match[1]
949 : stripcslashes( substr( $match[1], 1, -1 ) ) );
950 if ( $match[3] == '},' ) {
951 return $output;
952 }
953 } else {
954 $offset = $this->pg_array_parse( $text, $output, $limit, $offset + 1 );
955 }
956 } while ( $limit > $offset );
957
958 return $output;
959 }
960
961 public function aggregateValue( $valuedata, $valuename = 'value' ) {
962 return $valuedata;
963 }
964
965 public function getSoftwareLink() {
966 return '[{{int:version-db-postgres-url}} PostgreSQL]';
967 }
968
969 /**
970 * Return current schema (executes SELECT current_schema())
971 * Needs transaction
972 *
973 * @since 1.19
974 * @return string Default schema for the current session
975 */
976 public function getCurrentSchema() {
977 $res = $this->query( "SELECT current_schema()", __METHOD__ );
978 $row = $this->fetchRow( $res );
979
980 return $row[0];
981 }
982
983 /**
984 * Return list of schemas which are accessible without schema name
985 * This is list does not contain magic keywords like "$user"
986 * Needs transaction
987 *
988 * @see getSearchPath()
989 * @see setSearchPath()
990 * @since 1.19
991 * @return array List of actual schemas for the current sesson
992 */
993 public function getSchemas() {
994 $res = $this->query( "SELECT current_schemas(false)", __METHOD__ );
995 $row = $this->fetchRow( $res );
996 $schemas = [];
997
998 /* PHP pgsql support does not support array type, "{a,b}" string is returned */
999
1000 return $this->pg_array_parse( $row[0], $schemas );
1001 }
1002
1003 /**
1004 * Return search patch for schemas
1005 * This is different from getSchemas() since it contain magic keywords
1006 * (like "$user").
1007 * Needs transaction
1008 *
1009 * @since 1.19
1010 * @return array How to search for table names schemas for the current user
1011 */
1012 public function getSearchPath() {
1013 $res = $this->query( "SHOW search_path", __METHOD__ );
1014 $row = $this->fetchRow( $res );
1015
1016 /* PostgreSQL returns SHOW values as strings */
1017
1018 return explode( ",", $row[0] );
1019 }
1020
1021 /**
1022 * Update search_path, values should already be sanitized
1023 * Values may contain magic keywords like "$user"
1024 * @since 1.19
1025 *
1026 * @param array $search_path List of schemas to be searched by default
1027 */
1028 private function setSearchPath( $search_path ) {
1029 $this->query( "SET search_path = " . implode( ", ", $search_path ) );
1030 }
1031
1032 /**
1033 * Determine default schema for the current application
1034 * Adjust this session schema search path if desired schema exists
1035 * and is not alread there.
1036 *
1037 * We need to have name of the core schema stored to be able
1038 * to query database metadata.
1039 *
1040 * This will be also called by the installer after the schema is created
1041 *
1042 * @since 1.19
1043 *
1044 * @param string $desiredSchema
1045 */
1046 public function determineCoreSchema( $desiredSchema ) {
1047 $this->begin( __METHOD__, self::TRANSACTION_INTERNAL );
1048 if ( $this->schemaExists( $desiredSchema ) ) {
1049 if ( in_array( $desiredSchema, $this->getSchemas() ) ) {
1050 $this->coreSchema = $desiredSchema;
1051 $this->queryLogger->debug(
1052 "Schema \"" . $desiredSchema . "\" already in the search path\n" );
1053 } else {
1054 /**
1055 * Prepend our schema (e.g. 'mediawiki') in front
1056 * of the search path
1057 * Fixes T17816
1058 */
1059 $search_path = $this->getSearchPath();
1060 array_unshift( $search_path,
1061 $this->addIdentifierQuotes( $desiredSchema ) );
1062 $this->setSearchPath( $search_path );
1063 $this->coreSchema = $desiredSchema;
1064 $this->queryLogger->debug(
1065 "Schema \"" . $desiredSchema . "\" added to the search path\n" );
1066 }
1067 } else {
1068 $this->coreSchema = $this->getCurrentSchema();
1069 $this->queryLogger->debug(
1070 "Schema \"" . $desiredSchema . "\" not found, using current \"" .
1071 $this->coreSchema . "\"\n" );
1072 }
1073 /* Commit SET otherwise it will be rollbacked on error or IGNORE SELECT */
1074 $this->commit( __METHOD__, self::FLUSHING_INTERNAL );
1075 }
1076
1077 /**
1078 * Return schema name for core application tables
1079 *
1080 * @since 1.19
1081 * @return string Core schema name
1082 */
1083 public function getCoreSchema() {
1084 return $this->coreSchema;
1085 }
1086
1087 /**
1088 * Return schema names for temporary tables and core application tables
1089 *
1090 * @since 1.31
1091 * @return string[] schema names
1092 */
1093 public function getCoreSchemas() {
1094 if ( $this->tempSchema ) {
1095 return [ $this->tempSchema, $this->getCoreSchema() ];
1096 }
1097
1098 $res = $this->query(
1099 "SELECT nspname FROM pg_catalog.pg_namespace n WHERE n.oid = pg_my_temp_schema()", __METHOD__
1100 );
1101 $row = $this->fetchObject( $res );
1102 if ( $row ) {
1103 $this->tempSchema = $row->nspname;
1104 return [ $this->tempSchema, $this->getCoreSchema() ];
1105 }
1106
1107 return [ $this->getCoreSchema() ];
1108 }
1109
1110 public function getServerVersion() {
1111 if ( !isset( $this->numericVersion ) ) {
1112 $conn = $this->getBindingHandle();
1113 $versionInfo = pg_version( $conn );
1114 if ( version_compare( $versionInfo['client'], '7.4.0', 'lt' ) ) {
1115 // Old client, abort install
1116 $this->numericVersion = '7.3 or earlier';
1117 } elseif ( isset( $versionInfo['server'] ) ) {
1118 // Normal client
1119 $this->numericVersion = $versionInfo['server'];
1120 } else {
1121 // T18937: broken pgsql extension from PHP<5.3
1122 $this->numericVersion = pg_parameter_status( $conn, 'server_version' );
1123 }
1124 }
1125
1126 return $this->numericVersion;
1127 }
1128
1129 /**
1130 * Query whether a given relation exists (in the given schema, or the
1131 * default mw one if not given)
1132 * @param string $table
1133 * @param array|string $types
1134 * @param bool|string $schema
1135 * @return bool
1136 */
1137 private function relationExists( $table, $types, $schema = false ) {
1138 if ( !is_array( $types ) ) {
1139 $types = [ $types ];
1140 }
1141 if ( $schema === false ) {
1142 $schemas = $this->getCoreSchemas();
1143 } else {
1144 $schemas = [ $schema ];
1145 }
1146 $table = $this->realTableName( $table, 'raw' );
1147 $etable = $this->addQuotes( $table );
1148 foreach ( $schemas as $schema ) {
1149 $eschema = $this->addQuotes( $schema );
1150 $sql = "SELECT 1 FROM pg_catalog.pg_class c, pg_catalog.pg_namespace n "
1151 . "WHERE c.relnamespace = n.oid AND c.relname = $etable AND n.nspname = $eschema "
1152 . "AND c.relkind IN ('" . implode( "','", $types ) . "')";
1153 $res = $this->query( $sql );
1154 if ( $res && $res->numRows() ) {
1155 return true;
1156 }
1157 }
1158
1159 return false;
1160 }
1161
1162 /**
1163 * For backward compatibility, this function checks both tables and views.
1164 * @param string $table
1165 * @param string $fname
1166 * @param bool|string $schema
1167 * @return bool
1168 */
1169 public function tableExists( $table, $fname = __METHOD__, $schema = false ) {
1170 return $this->relationExists( $table, [ 'r', 'v' ], $schema );
1171 }
1172
1173 public function sequenceExists( $sequence, $schema = false ) {
1174 return $this->relationExists( $sequence, 'S', $schema );
1175 }
1176
1177 public function triggerExists( $table, $trigger ) {
1178 $q = <<<SQL
1179 SELECT 1 FROM pg_class, pg_namespace, pg_trigger
1180 WHERE relnamespace=pg_namespace.oid AND relkind='r'
1181 AND tgrelid=pg_class.oid
1182 AND nspname=%s AND relname=%s AND tgname=%s
1183 SQL;
1184 foreach ( $this->getCoreSchemas() as $schema ) {
1185 $res = $this->query(
1186 sprintf(
1187 $q,
1188 $this->addQuotes( $schema ),
1189 $this->addQuotes( $table ),
1190 $this->addQuotes( $trigger )
1191 )
1192 );
1193 if ( $res && $res->numRows() ) {
1194 return true;
1195 }
1196 }
1197
1198 return false;
1199 }
1200
1201 public function ruleExists( $table, $rule ) {
1202 $exists = $this->selectField( 'pg_rules', 'rulename',
1203 [
1204 'rulename' => $rule,
1205 'tablename' => $table,
1206 'schemaname' => $this->getCoreSchemas()
1207 ]
1208 );
1209
1210 return $exists === $rule;
1211 }
1212
1213 public function constraintExists( $table, $constraint ) {
1214 foreach ( $this->getCoreSchemas() as $schema ) {
1215 $sql = sprintf( "SELECT 1 FROM information_schema.table_constraints " .
1216 "WHERE constraint_schema = %s AND table_name = %s AND constraint_name = %s",
1217 $this->addQuotes( $schema ),
1218 $this->addQuotes( $table ),
1219 $this->addQuotes( $constraint )
1220 );
1221 $res = $this->query( $sql );
1222 if ( $res && $res->numRows() ) {
1223 return true;
1224 }
1225 }
1226 return false;
1227 }
1228
1229 /**
1230 * Query whether a given schema exists. Returns true if it does, false if it doesn't.
1231 * @param string $schema
1232 * @return bool
1233 */
1234 public function schemaExists( $schema ) {
1235 if ( !strlen( $schema ) ) {
1236 return false; // short-circuit
1237 }
1238
1239 $exists = $this->selectField(
1240 '"pg_catalog"."pg_namespace"', 1, [ 'nspname' => $schema ], __METHOD__ );
1241
1242 return (bool)$exists;
1243 }
1244
1245 /**
1246 * Returns true if a given role (i.e. user) exists, false otherwise.
1247 * @param string $roleName
1248 * @return bool
1249 */
1250 public function roleExists( $roleName ) {
1251 $exists = $this->selectField( '"pg_catalog"."pg_roles"', 1,
1252 [ 'rolname' => $roleName ], __METHOD__ );
1253
1254 return (bool)$exists;
1255 }
1256
1257 /**
1258 * @param string $table
1259 * @param string $field
1260 * @return PostgresField|null
1261 */
1262 public function fieldInfo( $table, $field ) {
1263 return PostgresField::fromText( $this, $table, $field );
1264 }
1265
1266 /**
1267 * pg_field_type() wrapper
1268 * @param ResultWrapper|resource $res ResultWrapper or PostgreSQL query result resource
1269 * @param int $index Field number, starting from 0
1270 * @return string
1271 */
1272 public function fieldType( $res, $index ) {
1273 if ( $res instanceof ResultWrapper ) {
1274 $res = $res->result;
1275 }
1276
1277 return pg_field_type( $res, $index );
1278 }
1279
1280 public function encodeBlob( $b ) {
1281 return new PostgresBlob( pg_escape_bytea( $b ) );
1282 }
1283
1284 public function decodeBlob( $b ) {
1285 if ( $b instanceof PostgresBlob ) {
1286 $b = $b->fetch();
1287 } elseif ( $b instanceof Blob ) {
1288 return $b->fetch();
1289 }
1290
1291 return pg_unescape_bytea( $b );
1292 }
1293
1294 public function strencode( $s ) {
1295 // Should not be called by us
1296 return pg_escape_string( $this->getBindingHandle(), (string)$s );
1297 }
1298
1299 public function addQuotes( $s ) {
1300 $conn = $this->getBindingHandle();
1301
1302 if ( is_null( $s ) ) {
1303 return 'NULL';
1304 } elseif ( is_bool( $s ) ) {
1305 return intval( $s );
1306 } elseif ( $s instanceof Blob ) {
1307 if ( $s instanceof PostgresBlob ) {
1308 $s = $s->fetch();
1309 } else {
1310 $s = pg_escape_bytea( $conn, $s->fetch() );
1311 }
1312 return "'$s'";
1313 } elseif ( $s instanceof NextSequenceValue ) {
1314 return 'DEFAULT';
1315 }
1316
1317 return "'" . pg_escape_string( $conn, (string)$s ) . "'";
1318 }
1319
1320 public function makeSelectOptions( $options ) {
1321 $preLimitTail = $postLimitTail = '';
1322 $startOpts = $useIndex = $ignoreIndex = '';
1323
1324 $noKeyOptions = [];
1325 foreach ( $options as $key => $option ) {
1326 if ( is_numeric( $key ) ) {
1327 $noKeyOptions[$option] = true;
1328 }
1329 }
1330
1331 $preLimitTail .= $this->makeGroupByWithHaving( $options );
1332
1333 $preLimitTail .= $this->makeOrderBy( $options );
1334
1335 if ( isset( $options['FOR UPDATE'] ) ) {
1336 $postLimitTail .= ' FOR UPDATE OF ' .
1337 implode( ', ', array_map( [ $this, 'tableName' ], $options['FOR UPDATE'] ) );
1338 } elseif ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
1339 $postLimitTail .= ' FOR UPDATE';
1340 }
1341
1342 if ( isset( $noKeyOptions['DISTINCT'] ) || isset( $noKeyOptions['DISTINCTROW'] ) ) {
1343 $startOpts .= 'DISTINCT';
1344 }
1345
1346 return [ $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ];
1347 }
1348
1349 public function buildConcat( $stringList ) {
1350 return implode( ' || ', $stringList );
1351 }
1352
1353 public function buildGroupConcatField(
1354 $delimiter, $table, $field, $conds = '', $options = [], $join_conds = []
1355 ) {
1356 $fld = "array_to_string(array_agg($field)," . $this->addQuotes( $delimiter ) . ')';
1357
1358 return '(' . $this->selectSQLText( $table, $fld, $conds, null, [], $join_conds ) . ')';
1359 }
1360
1361 public function buildStringCast( $field ) {
1362 return $field . '::text';
1363 }
1364
1365 public function streamStatementEnd( &$sql, &$newLine ) {
1366 # Allow dollar quoting for function declarations
1367 if ( substr( $newLine, 0, 4 ) == '$mw$' ) {
1368 if ( $this->delimiter ) {
1369 $this->delimiter = false;
1370 } else {
1371 $this->delimiter = ';';
1372 }
1373 }
1374
1375 return parent::streamStatementEnd( $sql, $newLine );
1376 }
1377
1378 public function doLockTables( array $read, array $write, $method ) {
1379 $tablesWrite = [];
1380 foreach ( $write as $table ) {
1381 $tablesWrite[] = $this->tableName( $table );
1382 }
1383 $tablesRead = [];
1384 foreach ( $read as $table ) {
1385 $tablesRead[] = $this->tableName( $table );
1386 }
1387
1388 // Acquire locks for the duration of the current transaction...
1389 if ( $tablesWrite ) {
1390 $this->query(
1391 'LOCK TABLE ONLY ' . implode( ',', $tablesWrite ) . ' IN EXCLUSIVE MODE',
1392 $method
1393 );
1394 }
1395 if ( $tablesRead ) {
1396 $this->query(
1397 'LOCK TABLE ONLY ' . implode( ',', $tablesRead ) . ' IN SHARE MODE',
1398 $method
1399 );
1400 }
1401
1402 return true;
1403 }
1404
1405 public function lockIsFree( $lockName, $method ) {
1406 if ( !parent::lockIsFree( $lockName, $method ) ) {
1407 return false; // already held
1408 }
1409 // http://www.postgresql.org/docs/9.2/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
1410 $key = $this->addQuotes( $this->bigintFromLockName( $lockName ) );
1411 $result = $this->query( "SELECT (CASE(pg_try_advisory_lock($key))
1412 WHEN 'f' THEN 'f' ELSE pg_advisory_unlock($key) END) AS lockstatus", $method );
1413 $row = $this->fetchObject( $result );
1414
1415 return ( $row->lockstatus === 't' );
1416 }
1417
1418 public function lock( $lockName, $method, $timeout = 5 ) {
1419 // http://www.postgresql.org/docs/9.2/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
1420 $key = $this->addQuotes( $this->bigintFromLockName( $lockName ) );
1421 $loop = new WaitConditionLoop(
1422 function () use ( $lockName, $key, $timeout, $method ) {
1423 $res = $this->query( "SELECT pg_try_advisory_lock($key) AS lockstatus", $method );
1424 $row = $this->fetchObject( $res );
1425 if ( $row->lockstatus === 't' ) {
1426 parent::lock( $lockName, $method, $timeout ); // record
1427 return true;
1428 }
1429
1430 return WaitConditionLoop::CONDITION_CONTINUE;
1431 },
1432 $timeout
1433 );
1434
1435 return ( $loop->invoke() === $loop::CONDITION_REACHED );
1436 }
1437
1438 public function unlock( $lockName, $method ) {
1439 // http://www.postgresql.org/docs/9.2/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
1440 $key = $this->addQuotes( $this->bigintFromLockName( $lockName ) );
1441 $result = $this->query( "SELECT pg_advisory_unlock($key) as lockstatus", $method );
1442 $row = $this->fetchObject( $result );
1443
1444 if ( $row->lockstatus === 't' ) {
1445 parent::unlock( $lockName, $method ); // record
1446 return true;
1447 }
1448
1449 $this->queryLogger->debug( __METHOD__ . " failed to release lock\n" );
1450
1451 return false;
1452 }
1453
1454 public function serverIsReadOnly() {
1455 $res = $this->query( "SHOW default_transaction_read_only", __METHOD__ );
1456 $row = $this->fetchObject( $res );
1457
1458 return $row ? ( strtolower( $row->default_transaction_read_only ) === 'on' ) : false;
1459 }
1460
1461 /**
1462 * @param string $lockName
1463 * @return string Integer
1464 */
1465 private function bigintFromLockName( $lockName ) {
1466 return \Wikimedia\base_convert( substr( sha1( $lockName ), 0, 15 ), 16, 10 );
1467 }
1468 }
1469
1470 /**
1471 * @deprecated since 1.29
1472 */
1473 class_alias( DatabasePostgres::class, 'DatabasePostgres' );