Simulate apps database schema update on upgrade

When upgrade, also simulate the database schema update for apps before
doing the actual upgrade.

4 files changed, 95 insertions, 37 deletions

diff --git a/lib/private/app.php b/lib/private/app.php
index 52f77535a52..2650ad98bc6 100644
--- a/lib/private/app.php
+++ b/lib/private/app.php
@@ -875,6 +875,18 @@ class OC_App {
 		}
 	}
 
+	public static function shouldUpgrade($app) {
+		$versions = self::getAppVersions();
+		$currentVersion = OC_App::getAppVersion($app);
+		if ($currentVersion) {
+			$installedVersion = $versions[$app];
+			if (version_compare($currentVersion, $installedVersion, '>')) {
+				return true;
+			}
+		}
+		return false;
+	}
+
 	/**
 	 * check if the app needs updating and update when needed
 	 *
@@ -885,26 +897,27 @@ class OC_App {
 			return;
 		}
 		self::$checkedApps[] = $app;
+		if (!self::shouldUpgrade($app)) {
+			return;
+		}
 		$versions = self::getAppVersions();
+		$installedVersion = $versions[$app];
 		$currentVersion = OC_App::getAppVersion($app);
-		if ($currentVersion) {
-			$installedVersion = $versions[$app];
-			if (version_compare($currentVersion, $installedVersion, '>')) {
-				$info = self::getAppInfo($app);
-				OC_Log::write($app,
-					'starting app upgrade from ' . $installedVersion . ' to ' . $currentVersion,
-					OC_Log::DEBUG);
-				try {
-					OC_App::updateApp($app);
-					OC_Hook::emit('update', 'success', 'Updated ' . $info['name'] . ' app');
-				} catch (Exception $e) {
-					OC_Hook::emit('update', 'failure', 'Failed to update ' . $info['name'] . ' app: ' . $e->getMessage());
-					$l = OC_L10N::get('lib');
-					throw new RuntimeException($l->t('Failed to upgrade "%s".', array($app)), 0, $e);
-				}
-				OC_Appconfig::setValue($app, 'installed_version', OC_App::getAppVersion($app));
-			}
+		OC_Log::write(
+			$app,
+			'starting app upgrade from ' . $installedVersion . ' to ' . $currentVersion,
+			OC_Log::DEBUG
+		);
+		$info = self::getAppInfo($app);
+		try {
+			OC_App::updateApp($app);
+			OC_Hook::emit('update', 'success', 'Updated ' . $info['name'] . ' app');
+		} catch (Exception $e) {
+			OC_Hook::emit('update', 'failure', 'Failed to update ' . $info['name'] . ' app: ' . $e->getMessage());
+			$l = OC_L10N::get('lib');
+			throw new RuntimeException($l->t('Failed to upgrade "%s".', array($app)), 0, $e);
 		}
+		OC_Appconfig::setValue($app, 'installed_version', OC_App::getAppVersion($app));
 	}
 
 	/**
diff --git a/lib/private/db.php b/lib/private/db.php
index 422f783c745..f6854e3e162 100644
--- a/lib/private/db.php
+++ b/lib/private/db.php
@@ -307,15 +307,21 @@ class OC_DB {
 	/**
 	 * update the database schema
 	 * @param string $file file to read structure from
+	 * @param bool $simulate whether to simulate the upgrade on separate tables
 	 * @throws Exception
 	 * @return string|boolean
 	 */
-	public static function updateDbFromStructure($file) {
+	public static function updateDbFromStructure($file, $simulate = false) {
 		$schemaManager = self::getMDB2SchemaManager();
 		try {
-			$result = $schemaManager->updateDbFromStructure($file);
+			$result = $schemaManager->updateDbFromStructure($file, false, $simulate);
 		} catch (Exception $e) {
-			OC_Log::write('core', 'Failed to update database structure ('.$e.')', OC_Log::FATAL);
+			if ($simulate) {
+				OC_Log::write('core', 'Database structure update simulation failed ('.$e.')', OC_Log::FATAL);
+			}
+			else {
+				OC_Log::write('core', 'Failed to update database structure ('.$e.')', OC_Log::FATAL);
+			}
 			throw $e;
 		}
 		return $result;
diff --git a/lib/private/db/mdb2schemamanager.php b/lib/private/db/mdb2schemamanager.php
index 533ed9110e7..397aaf3608a 100644
--- a/lib/private/db/mdb2schemamanager.php
+++ b/lib/private/db/mdb2schemamanager.php
@@ -77,9 +77,10 @@ class MDB2SchemaManager {
 	 * update the database scheme
 	 * @param string $file file to read structure from
 	 * @param bool $generateSql only return the sql needed for the upgrade
+	 * @param bool $simulate whether to simulate on separate tables instead of the real onces
 	 * @return string|boolean
 	 */
-	public function updateDbFromStructure($file, $generateSql = false) {
+	public function updateDbFromStructure($file, $generateSql = false, $simulate = false) {
 
 		$platform = $this->conn->getDatabasePlatform();
 		$schemaReader = new MDB2SchemaReader(\OC_Config::getObject(), $platform);
@@ -89,8 +90,12 @@ class MDB2SchemaManager {
 		if ($generateSql) {
 			return $migrator->generateChangeScript($toSchema);
 		} else {
-			$migrator->checkMigrate($toSchema);
-			$migrator->migrate($toSchema);
+			if ($simulate) {
+				$migrator->checkMigrate($toSchema);
+			}
+			else {
+				$migrator->migrate($toSchema);
+			}
 			return true;
 		}
 	}
diff --git a/lib/private/updater.php b/lib/private/updater.php
index 58d3cab73aa..1c363123e10 100644
--- a/lib/private/updater.php
+++ b/lib/private/updater.php
@@ -125,29 +125,63 @@ class Updater extends BasicEmitter {
 		 * STOP CONFIG CHANGES FOR OLDER VERSIONS
 		 */
 
+		$canUpgrade = false;
 
+		// simulate DB upgrade
 		try {
-			\OC_DB::updateDbFromStructure(\OC::$SERVERROOT . '/db_structure.xml');
-			$this->emit('\OC\Updater', 'dbUpgrade');
-
+			// simulate core DB upgrade
+			\OC_DB::updateDbFromStructure(\OC::$SERVERROOT . '/db_structure.xml', true);
+
+			// simulate apps DB upgrade
+			$version = \OC_Util::getVersion();
+			$apps = \OC_App::getEnabledApps();
+			foreach ($apps as $appId) {
+				$info = \OC_App::getAppInfo($appId);
+				if (\OC_App::isAppCompatible($version, $info) && \OC_App::shouldUpgrade($appId)) {
+					if (file_exists(\OC_App::getAppPath($appId) . '/appinfo/database.xml')) {
+						\OC_DB::updateDbFromStructure(\OC_App::getAppPath($appId) . '/appinfo/database.xml', true);
+					}
+				}
+			}
+
+			$this->emit('\OC\Updater', 'dbSimulateUpgrade');
+
+			$canUpgrade = true;
 		} catch (\Exception $exception) {
 			$this->emit('\OC\Updater', 'failure', array($exception->getMessage()));
 		}
-		\OC_Config::setValue('version', implode('.', \OC_Util::getVersion()));
-		$disabledApps = \OC_App::checkAppsRequirements();
-		if (!empty($disabledApps)) {
-			$this->emit('\OC\Updater', 'disabledApps', array($disabledApps));
-		}
-		// load all apps to also upgrade enabled apps
-		\OC_App::loadApps();
 
-		$repair = new Repair();
-		$repair->run();
+		if ($canUpgrade) {
+			// proceed with real upgrade
+			try {
+				// do the real upgrade
+				\OC_DB::updateDbFromStructure(\OC::$SERVERROOT . '/db_structure.xml');
+				$this->emit('\OC\Updater', 'dbUpgrade');
+
+			} catch (\Exception $exception) {
+				$this->emit('\OC\Updater', 'failure', array($exception->getMessage()));
+				return false;
+			}
+			// TODO: why not do this at the end ?
+			\OC_Config::setValue('version', implode('.', \OC_Util::getVersion()));
+			$disabledApps = \OC_App::checkAppsRequirements();
+			if (!empty($disabledApps)) {
+				$this->emit('\OC\Updater', 'disabledApps', array($disabledApps));
+			}
+			// load all apps to also upgrade enabled apps
+			\OC_App::loadApps();
+
+			$repair = new Repair();
+			$repair->run();
+
+			//Invalidate update feed
+			\OC_Appconfig::setValue('core', 'lastupdatedat', 0);
+		}
 
-		//Invalidate update feed
-		\OC_Appconfig::setValue('core', 'lastupdatedat', 0);
 		\OC_Config::setValue('maintenance', false);
 		$this->emit('\OC\Updater', 'maintenanceEnd');
+
+		return $canUpgrade;
 	}
 
 }