lib/private/DB/Adapter.php
<?php
/**
* @author Bart Visscher <bartv@thisnet.nl>
* @author Joas Schilling <coding@schilljs.com>
* @author Jonny007-MKD <1-23-4-5@web.de>
* @author Morris Jobke <hey@morrisjobke.de>
* @author Robin Appelman <icewind@owncloud.com>
* @author Thomas Müller <thomas.mueller@tmit.eu>
* @author Tom Needham <tom@owncloud.com>
*
* @copyright Copyright (c) 2018, ownCloud GmbH
* @license AGPL-3.0
*
* This code is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License, version 3,
* along with this program. If not, see <http://www.gnu.org/licenses/>
*
*/
namespace OC\DB;
use Doctrine\DBAL\Exception\DriverException;
use Doctrine\DBAL\Exception\UniqueConstraintViolationException;
use Doctrine\DBAL\Platforms\OraclePlatform;
/**
* This handles the way we use to write queries, into something that can be
* handled by the database abstraction layer.
*/
class Adapter {
/**
* @var \OC\DB\Connection $conn
*/
protected $conn;
public function __construct($conn) {
$this->conn = $conn;
}
/**
* @param string $table name
* @return int id of last insert statement
*/
public function lastInsertId($table) {
return $this->conn->realLastInsertId($table);
}
/**
* @param string $statement that needs to be changed so the db can handle it
* @return string changed statement
*/
public function fixupStatement($statement) {
return $statement;
}
/**
* Create an exclusive read+write lock on a table
*
* @param string $tableName
* @since 9.1.0
*/
public function lockTable($tableName) {
$this->conn->beginTransaction();
$this->conn->executeUpdate('LOCK TABLE `' .$tableName . '` IN EXCLUSIVE MODE');
}
/**
* Release a previous acquired lock again
*
* @since 9.1.0
*/
public function unlockTable() {
$this->conn->commit();
}
/**
* Insert a row if the matching row does not exist.
*
* @param string $table The table name (will replace *PREFIX* with the actual prefix)
* @param array $input data that should be inserted into the table (column name => value)
* @param array|null $compare List of values that should be checked for "if not exists"
* If this is null or an empty array, all keys of $input will be compared
* Please note: text fields (clob) must not be used in the compare array
* @return int number of inserted rows
* @throws \Doctrine\DBAL\DBALException
*/
public function insertIfNotExist($table, $input, array $compare = null) {
if (empty($compare)) {
$compare = \array_keys($input);
}
$query = 'INSERT INTO `' . $table . '` (`'
. \implode('`,`', \array_keys($input)) . '`) SELECT '
. \str_repeat('?,', \count($input) - 1) . '? ' // Is there a prettier alternative?
. 'FROM `' . $table . '` WHERE ';
$inserts = \array_values($input);
foreach ($compare as $key) {
$query .= '`' . $key . '`';
if ($input[$key] === null) {
$query .= ' IS NULL AND ';
} else {
$inserts[] = $input[$key];
$query .= ' = ? AND ';
}
}
$query = \substr($query, 0, \strlen($query) - 5);
$query .= ' HAVING COUNT(*) = 0';
return $this->conn->executeUpdate($query, $inserts);
}
/**
* Inserts, or updates a row into the database. Returns the inserted or updated rows
* @param $table string table name including **PREFIX**
* @param $input array the key=>value pairs to insert into the db row
* @param $compare array columns that should be compared to look for existing arrays
* @return int the number of rows affected by the operation
* @throws DriverException|\RuntimeException
*/
public function upsert($table, $input, $compare) {
$this->conn->beginTransaction();
$done = false;
if (empty($compare)) {
$compare = \array_keys($input);
}
// Construct the update query
$qbu = $this->conn->getQueryBuilder();
$qbu->update($table);
foreach ($input as $col => $val) {
$qbu->set($col, $qbu->createParameter($col))
->setParameter($col, $val);
}
foreach ($compare as $key) {
if ($input[$key] === null || ($input[$key] === '' && $this->conn->getDatabasePlatform() instanceof OraclePlatform)) {
$qbu->andWhere($qbu->expr()->isNull($key));
} else {
if ($this->conn->getDatabasePlatform() instanceof OraclePlatform) {
$qbu->andWhere(
$qbu->expr()->eq(
// needs to cast to char in order to compare with char
$qbu->createFunction('to_char(`'.$key.'`)'), // TODO does this handle empty strings on oracle correctly
$qbu->expr()->literal($input[$key])
)
);
} else {
$qbu->andWhere(
$qbu->expr()->eq(
$key,
$qbu->expr()->literal($input[$key])
)
);
}
}
}
// Construct the insert query
$qbi = $this->conn->getQueryBuilder();
$qbi->insert($table);
foreach ($input as $c => $v) {
$qbi->setValue($c, $qbi->createParameter($c))
->setParameter($c, $v);
}
$rows = 0;
$count = 0;
// Attempt 5 times before failing the upsert
$maxTry = 5;
while (!$done && $count < $maxTry) {
try {
// Try to update
$rows = $qbu->execute();
} catch (DriverException $e) {
// Skip deadlock and retry
// @TODO when we update to DBAL 2.6 we can use DeadlockExceptions here
if ($e->getErrorCode() == 1213) {
$count++;
continue;
} else {
// We should catch other exceptions up the stack
$this->conn->rollBack();
throw $e;
}
}
if ($rows > 0) {
// We altered some rows, return
$done = true;
} else {
// Try the insert
$this->conn->beginTransaction();
try {
// Execute the insert query
$rows = $qbi->execute();
$done = $rows > 0;
} catch (UniqueConstraintViolationException $e) {
// Catch the unique violation and try the loop again
$count++;
}
// Other exceptions are not caught, they should be caught up the stack
$this->conn->commit();
}
}
// Pass through failures correctly
if ($count === $maxTry) {
$params = \implode(',', $input);
$updateQuery = $qbu->getSQL();
$insertQuery = $qbi->getSQL();
throw new \RuntimeException("DB upsert failed after $count attempts. UpdateQuery: $updateQuery InsertQuery: $insertQuery");
}
$this->conn->commit();
return $rows;
}
}