1 files changed, 292 insertions, 0 deletions
diff --git a/lib/private/DB/Migrator.php b/lib/private/DB/Migrator.php
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+++ b/lib/private/DB/Migrator.php
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+<?php
+/**
+ * @author martin-rueegg <martin.rueegg@metaworx.ch>
+ * @author Morris Jobke <hey@morrisjobke.de>
+ * @author Robin Appelman <icewind@owncloud.com>
+ * @author tbelau666 <thomas.belau@gmx.de>
+ * @author Thomas Müller <thomas.mueller@tmit.eu>
+ * @author Victor Dubiniuk <dubiniuk@owncloud.com>
+ * @author Vincent Petry <pvince81@owncloud.com>
+ *
+ * @copyright Copyright (c) 2016, ownCloud, Inc.
+ * @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\DBALException;
+use \Doctrine\DBAL\Schema\Index;
+use \Doctrine\DBAL\Schema\Table;
+use \Doctrine\DBAL\Schema\Schema;
+use \Doctrine\DBAL\Schema\SchemaConfig;
+use \Doctrine\DBAL\Schema\Comparator;
+use OCP\IConfig;
+use OCP\Security\ISecureRandom;
+use Symfony\Component\EventDispatcher\EventDispatcher;
+use Symfony\Component\EventDispatcher\GenericEvent;
+
+class Migrator {
+
+	/**
+	 * @var \Doctrine\DBAL\Connection $connection
+	 */
+	protected $connection;
+
+	/**
+	 * @var ISecureRandom
+	 */
+	private $random;
+
+	/** @var IConfig */
+	protected $config;
+
+	/** @var EventDispatcher  */
+	private $dispatcher;
+
+	/** @var bool */
+	private $noEmit = false;
+
+	/**
+	 * @param \Doctrine\DBAL\Connection|Connection $connection
+	 * @param ISecureRandom $random
+	 * @param IConfig $config
+	 * @param EventDispatcher $dispatcher
+	 */
+	public function __construct(\Doctrine\DBAL\Connection $connection,
+								ISecureRandom $random,
+								IConfig $config,
+								EventDispatcher $dispatcher = null) {
+		$this->connection = $connection;
+		$this->random = $random;
+		$this->config = $config;
+		$this->dispatcher = $dispatcher;
+	}
+
+	/**
+	 * @param \Doctrine\DBAL\Schema\Schema $targetSchema
+	 */
+	public function migrate(Schema $targetSchema) {
+		$this->noEmit = true;
+		$this->applySchema($targetSchema);
+	}
+
+	/**
+	 * @param \Doctrine\DBAL\Schema\Schema $targetSchema
+	 * @return string
+	 */
+	public function generateChangeScript(Schema $targetSchema) {
+		$schemaDiff = $this->getDiff($targetSchema, $this->connection);
+
+		$script = '';
+		$sqls = $schemaDiff->toSql($this->connection->getDatabasePlatform());
+		foreach ($sqls as $sql) {
+			$script .= $this->convertStatementToScript($sql);
+		}
+
+		return $script;
+	}
+
+	/**
+	 * @param Schema $targetSchema
+	 * @throws \OC\DB\MigrationException
+	 */
+	public function checkMigrate(Schema $targetSchema) {
+		$this->noEmit = true;
+		/**@var \Doctrine\DBAL\Schema\Table[] $tables */
+		$tables = $targetSchema->getTables();
+		$filterExpression = $this->getFilterExpression();
+		$this->connection->getConfiguration()->
+			setFilterSchemaAssetsExpression($filterExpression);
+		$existingTables = $this->connection->getSchemaManager()->listTableNames();
+
+		$step = 0;
+		foreach ($tables as $table) {
+			if (strpos($table->getName(), '.')) {
+				list(, $tableName) = explode('.', $table->getName());
+			} else {
+				$tableName = $table->getName();
+			}
+			$this->emitCheckStep($tableName, $step++, count($tables));
+			// don't need to check for new tables
+			if (array_search($tableName, $existingTables) !== false) {
+				$this->checkTableMigrate($table);
+			}
+		}
+	}
+
+	/**
+	 * Create a unique name for the temporary table
+	 *
+	 * @param string $name
+	 * @return string
+	 */
+	protected function generateTemporaryTableName($name) {
+		return $this->config->getSystemValue('dbtableprefix', 'oc_') . $name . '_' . $this->random->generate(13, ISecureRandom::CHAR_LOWER . ISecureRandom::CHAR_DIGITS);
+	}
+
+	/**
+	 * Check the migration of a table on a copy so we can detect errors before messing with the real table
+	 *
+	 * @param \Doctrine\DBAL\Schema\Table $table
+	 * @throws \OC\DB\MigrationException
+	 */
+	protected function checkTableMigrate(Table $table) {
+		$name = $table->getName();
+		$tmpName = $this->generateTemporaryTableName($name);
+
+		$this->copyTable($name, $tmpName);
+
+		//create the migration schema for the temporary table
+		$tmpTable = $this->renameTableSchema($table, $tmpName);
+		$schemaConfig = new SchemaConfig();
+		$schemaConfig->setName($this->connection->getDatabase());
+		$schema = new Schema(array($tmpTable), array(), $schemaConfig);
+
+		try {
+			$this->applySchema($schema);
+			$this->dropTable($tmpName);
+		} catch (DBALException $e) {
+			// pgsql needs to commit it's failed transaction before doing anything else
+			if ($this->connection->isTransactionActive()) {
+				$this->connection->commit();
+			}
+			$this->dropTable($tmpName);
+			throw new MigrationException($table->getName(), $e->getMessage());
+		}
+	}
+
+	/**
+	 * @param \Doctrine\DBAL\Schema\Table $table
+	 * @param string $newName
+	 * @return \Doctrine\DBAL\Schema\Table
+	 */
+	protected function renameTableSchema(Table $table, $newName) {
+		/**
+		 * @var \Doctrine\DBAL\Schema\Index[] $indexes
+		 */
+		$indexes = $table->getIndexes();
+		$newIndexes = array();
+		foreach ($indexes as $index) {
+			if ($index->isPrimary()) {
+				// do not rename primary key
+				$indexName = $index->getName();
+			} else {
+				// avoid conflicts in index names
+				$indexName = $this->config->getSystemValue('dbtableprefix', 'oc_') . $this->random->generate(13, ISecureRandom::CHAR_LOWER);
+			}
+			$newIndexes[] = new Index($indexName, $index->getColumns(), $index->isUnique(), $index->isPrimary());
+		}
+
+		// foreign keys are not supported so we just set it to an empty array
+		return new Table($newName, $table->getColumns(), $newIndexes, array(), 0, $table->getOptions());
+	}
+
+	protected function getDiff(Schema $targetSchema, \Doctrine\DBAL\Connection $connection) {
+		$filterExpression = $this->getFilterExpression();
+		$this->connection->getConfiguration()->
+		setFilterSchemaAssetsExpression($filterExpression);
+		$sourceSchema = $connection->getSchemaManager()->createSchema();
+
+		// remove tables we don't know about
+		/** @var $table \Doctrine\DBAL\Schema\Table */
+		foreach ($sourceSchema->getTables() as $table) {
+			if (!$targetSchema->hasTable($table->getName())) {
+				$sourceSchema->dropTable($table->getName());
+			}
+		}
+		// remove sequences we don't know about
+		foreach ($sourceSchema->getSequences() as $table) {
+			if (!$targetSchema->hasSequence($table->getName())) {
+				$sourceSchema->dropSequence($table->getName());
+			}
+		}
+
+		$comparator = new Comparator();
+		return $comparator->compare($sourceSchema, $targetSchema);
+	}
+
+	/**
+	 * @param \Doctrine\DBAL\Schema\Schema $targetSchema
+	 * @param \Doctrine\DBAL\Connection $connection
+	 */
+	protected function applySchema(Schema $targetSchema, \Doctrine\DBAL\Connection $connection = null) {
+		if (is_null($connection)) {
+			$connection = $this->connection;
+		}
+
+		$schemaDiff = $this->getDiff($targetSchema, $connection);
+
+		$connection->beginTransaction();
+		$sqls = $schemaDiff->toSql($connection->getDatabasePlatform());
+		$step = 0;
+		foreach ($sqls as $sql) {
+			$this->emit($sql, $step++, count($sqls));
+			$connection->query($sql);
+		}
+		$connection->commit();
+	}
+
+	/**
+	 * @param string $sourceName
+	 * @param string $targetName
+	 */
+	protected function copyTable($sourceName, $targetName) {
+		$quotedSource = $this->connection->quoteIdentifier($sourceName);
+		$quotedTarget = $this->connection->quoteIdentifier($targetName);
+
+		$this->connection->exec('CREATE TABLE ' . $quotedTarget . ' (LIKE ' . $quotedSource . ')');
+		$this->connection->exec('INSERT INTO ' . $quotedTarget . ' SELECT * FROM ' . $quotedSource);
+	}
+
+	/**
+	 * @param string $name
+	 */
+	protected function dropTable($name) {
+		$this->connection->exec('DROP TABLE ' . $this->connection->quoteIdentifier($name));
+	}
+
+	/**
+	 * @param $statement
+	 * @return string
+	 */
+	protected function convertStatementToScript($statement) {
+		$script = $statement . ';';
+		$script .= PHP_EOL;
+		$script .= PHP_EOL;
+		return $script;
+	}
+
+	protected function getFilterExpression() {
+		return '/^' . preg_quote($this->config->getSystemValue('dbtableprefix', 'oc_')) . '/';
+	}
+
+	protected function emit($sql, $step, $max) {
+		if ($this->noEmit) {
+			return;
+		}
+		if(is_null($this->dispatcher)) {
+			return;
+		}
+		$this->dispatcher->dispatch('\OC\DB\Migrator::executeSql', new GenericEvent($sql, [$step+1, $max]));
+	}
+
+	private function emitCheckStep($tableName, $step, $max) {
+		if(is_null($this->dispatcher)) {
+			return;
+		}
+		$this->dispatcher->dispatch('\OC\DB\Migrator::checkTable', new GenericEvent($tableName, [$step+1, $max]));
+	}
+}