[FEATURE] Make Locking API configurable

Locking API can be configured via $GLOBALS['TYPO3_CONF_VARS'].

Now, by changing the priority of a specific lock strategy, it
can be effectively disabled.

Resolves: #87072
Releases: master
Change-Id: Ie632f470a2144f67206e40736a9f70f4296715fa
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/58940


Tested-by: Markus Klein <markus.klein@typo3.org>
Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Markus Klein <markus.klein@typo3.org>
Reviewed-by: Benni Mack <benni@typo3.org>

typo3/sysext/core/Classes/Locking/FileLockStrategy.php

@@ -27,6 +27,8 @@ class FileLockStrategy implements LockingStrategyInterface
 {
     const FILE_LOCK_FOLDER = 'lock/';
 
+    const DEFAULT_PRIORITY = 75;
+
     /**
      * @var resource File pointer if using flock method
      */
@@ -49,11 +51,17 @@ class FileLockStrategy implements LockingStrategyInterface
     public function __construct($subject)
     {
         /*
-         * Tests if the directory for simple locks is available.
+         * Tests if the directory for file locks is available.
          * If not, the directory will be created. The lock path is usually
          * below typo3temp/var, typo3temp/var itself should exist already (or root-path/var/ respectively)
          */
-        $path = Environment::getVarPath() . '/' . self::FILE_LOCK_FOLDER;
+        if ($GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][self::class]['lockFileDir'] ?? false) {
+            $path = Environment::getProjectPath() . '/'
+                . trim($GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][self::class]['lockFileDir'], ' /')
+                . '/';
+        } else {
+            $path = Environment::getVarPath() . '/' . self::FILE_LOCK_FOLDER;
+        }
         if (!is_dir($path)) {
             // Not using mkdir_deep on purpose here, if typo3temp itself
             // does not exist, this issue should be solved on a different
@@ -152,7 +160,8 @@ class FileLockStrategy implements LockingStrategyInterface
      */
     public static function getPriority()
     {
-        return 75;
+        return $GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][self::class]['priority']
+            ?? self::DEFAULT_PRIORITY;
     }
 
     /**

typo3/sysext/core/Classes/Locking/SemaphoreLockStrategy.php

@@ -26,6 +26,8 @@ class SemaphoreLockStrategy implements LockingStrategyInterface
 {
     const FILE_LOCK_FOLDER = 'lock/';
 
+    const DEFAULT_PRIORITY = 25;
+
     /**
      * @var mixed Identifier used for this lock
      */
@@ -52,7 +54,18 @@ class SemaphoreLockStrategy implements LockingStrategyInterface
      */
     public function __construct($subject)
     {
-        $path = Environment::getVarPath() . '/' . self::FILE_LOCK_FOLDER;
+        /*
+         * Tests if the directory for semaphore locks is available.
+         * If not, the directory will be created. The lock path is usually
+         * below typo3temp/var, typo3temp/var itself should exist already (or root-path/var/ respectively)
+         */
+        if ($GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][self::class]['lockFileDir'] ?? false) {
+            $path = Environment::getProjectPath() . '/'
+                    . trim($GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][self::class]['lockFileDir'], ' /')
+                    . '/';
+        } else {
+            $path = Environment::getVarPath() . '/' . self::FILE_LOCK_FOLDER;
+        }
         if (!is_dir($path)) {
             // Not using mkdir_deep on purpose here, if typo3temp/var itself
             // does not exist, this issue should be solved on a different
@@ -147,7 +160,8 @@ class SemaphoreLockStrategy implements LockingStrategyInterface
      */
     public static function getPriority()
     {
-        return 25;
+        return $GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][self::class]['priority']
+            ?? self::DEFAULT_PRIORITY;
     }
 
     /**

typo3/sysext/core/Classes/Locking/SimpleLockStrategy.php

@@ -26,6 +26,8 @@ class SimpleLockStrategy implements LockingStrategyInterface
 {
     const FILE_LOCK_FOLDER = 'lock/';
 
+    const DEFAULT_PRIORITY = 50;
+
     /**
      * @var string File path used for this lock
      */
@@ -55,7 +57,13 @@ class SimpleLockStrategy implements LockingStrategyInterface
         // Tests if the directory for simple locks is available.
         // If not, the directory will be created. The lock path is usually
         // below typo3temp/var, typo3temp/var itself should exist already (or getProjectPath . /var/ respectively)
-        $path = Environment::getVarPath() . '/' . self::FILE_LOCK_FOLDER;
+        if ($GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][self::class]['lockFileDir'] ?? false) {
+            $path = Environment::getProjectPath() . '/'
+                    . trim($GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][self::class]['lockFileDir'], ' /')
+                    . '/';
+        } else {
+            $path = Environment::getVarPath() . '/' . self::FILE_LOCK_FOLDER;
+        }
         if (!is_dir($path)) {
             // Not using mkdir_deep on purpose here, if typo3temp/var itself
             // does not exist, this issue should be solved on a different
@@ -183,7 +191,8 @@ class SimpleLockStrategy implements LockingStrategyInterface
      */
     public static function getPriority()
     {
-        return 50;
+        return $GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][self::class]['priority']
+            ?? self::DEFAULT_PRIORITY;
     }
 
     /**

typo3/sysext/core/Configuration/DefaultConfiguration.php

@@ -129,6 +129,34 @@ return [
                 'StaticValueMapper' => \TYPO3\CMS\Core\Routing\Aspect\StaticValueMapper::class,
             ],
         ],
+        'locking' => [
+            'strategies' => [
+                \TYPO3\CMS\Core\Locking\FileLockStrategy::class => [
+                    // if not set: use default priority of FileLockStrategy
+                    //'priority' => 75,
+
+                    // if not set: use default path of FileLockStrategy
+                    // If you change this, directory must exist!
+                    // 'lockFileDir' => 'typo3temp/var'
+                ],
+                \TYPO3\CMS\Core\Locking\SemaphoreLockStrategy::class => [
+                    // if not set: use default priority of SemaphoreLockStrategy
+                    // 'priority' => 50
+
+                    // empty: use default path of SemaphoreLockStrategy
+                    // If you change this, directory must exist!
+                    // 'lockFileDir' => 'typo3temp/var'
+                ],
+                \TYPO3\CMS\Core\Locking\SimpleLockStrategy::class => [
+                    // if not set: use default priority of SimpleLockStrategy
+                    //'priority' => 25,
+
+                    // empty: use default path of SimpleLockStrategy
+                    // If you change this, directory must exist!
+                    // 'lockFileDir' => 'typo3temp/var'
+                ]
+            ]
+        ],
         'caching' => [
             'cacheConfigurations' => [
                 // The cache_core cache is is for core php code only and must

typo3/sysext/core/Documentation/Changelog/master/Feature-87072-AddedConfigurationOptionsForLockingAddedConfigurationOptionsForLocking.rst

+.. include:: ../../Includes.txt
+
+=========================================================
+Feature: #87072 - Added Configuration Options for Locking
+=========================================================
+
+See :issue:`87072`
+
+Description
+===========
+
+With change `Feature: #47712 - New Locking API
+<https://docs.typo3.org/typo3cms/extensions/core/latest/Changelog/7.2/Feature-47712-NewLockingAPI.html>`__ a new Locking API was introduced.
+This API can be extended. It provides three locking strategies and an interface for adding your own locking strategy in an extension.
+However, until now, the default behaviour could not be changed using only the TYPO3 core.
+
+The introduction of new options makes some of the default properties of the locking API configurable:
+
+* The priority of each locking strategy can be changed.
+* The directory where the lock files are written can be configured.
+
+Configuration example
+---------------------
+
+typo3conf/AdditionalConfiguration.php::
+
+   <?php
+
+   if (!defined('TYPO3_MODE')) {
+       die('Access denied.');
+   }
+
+   $GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][\TYPO3\CMS\Core\Locking\FileLockStrategy::class]['priority'] = 10;
+   // The directory specified here must exist und must be a subdirectory of `Environment::getProjectPath()`
+   $GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][\TYPO3\CMS\Core\Locking\FileLockStrategy::class]['lockFileDir'] = 'mylockdir';
+
+
+This sets the priority of FileLockStrategy to 10, thus making it the locking strategy with the least priority, which
+will be chosen last by the LockFactory.
+
+The directory for storing the locks is changed to `mylockdir`.
+
+Impact
+======
+
+For administrators
+------------------
+
+Nothing changes by default. The default values are used for the Locking API, same as before this change.
+
+If AdditionalConfiguration.php is used to change Global Configuration settings for Locking API, and not used with care,
+it can seriously compromise the stability of the system. As usual, when overriding Global Configuration with
+LocalConfiguration.php or AdditionalConfiguration.php, great caution must be used.
+
+Specifically, do the following:
+
+* Test this on a test system first
+* If you change the priorities, make sure your system fully supports the locking strategy which will be chosen by default.
+* If you change the directory, make sure the directory exists and will always exist in the future.
+
+For developers
+--------------
+
+If a locking strategy is added by an extension, the priority and possibly directory for storing locks should be made
+configurable as well::
+
+   public static function getPriority()
+   {
+       return $GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][self::class]['priority']
+           ?? self::DEFAULT_PRIORITY;
+   }
+
+.. index:: ext:core

typo3/sysext/core/Tests/Unit/Locking/FileLockStrategyTest.php

@@ -42,4 +42,23 @@ class FileLockStrategyTest extends UnitTestCase
         $lock = $this->getAccessibleMock(FileLockStrategy::class, ['dummy'], ['999999999']);
         self::assertSame(Environment::getVarPath() . '/' . FileLockStrategy::FILE_LOCK_FOLDER . 'flock_' . md5('999999999'), $lock->_get('filePath'));
     }
+
+    /**
+     * @test
+     */
+    public function getPriorityReturnsDefaultPriority()
+    {
+        self::assertEquals(FileLockStrategy::getPriority(), FileLockStrategy::DEFAULT_PRIORITY);
+    }
+
+    /**
+     * @test
+     */
+    public function setPriority()
+    {
+        $GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][\TYPO3\CMS\Core\Locking\FileLockStrategy::class]['priority'] = 10;
+
+        self::assertEquals(10, FileLockStrategy::getPriority());
+        unset($GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][\TYPO3\CMS\Core\Locking\FileLockStrategy::class]['priority']);
+    }
 }

typo3/sysext/core/Tests/Unit/Locking/LockFactoryTest.php

@@ -19,6 +19,8 @@ use TYPO3\CMS\Core\Locking\FileLockStrategy;
 use TYPO3\CMS\Core\Locking\LockFactory;
 use TYPO3\CMS\Core\Locking\LockingStrategyInterface;
 use TYPO3\CMS\Core\Locking\SemaphoreLockStrategy;
+use TYPO3\CMS\Core\Locking\SimpleLockStrategy;
+use TYPO3\CMS\Core\Resource\File;
 use TYPO3\CMS\Core\Tests\Unit\Locking\Fixtures\DummyLock;
 use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
 
@@ -32,6 +34,11 @@ class LockFactoryTest extends UnitTestCase
      */
     protected $mockFactory;
 
+    /**
+     * @var array
+     */
+    protected $strategiesConfigBackup = [];
+
     /**
      * Set up the tests
      */
@@ -39,6 +46,21 @@ class LockFactoryTest extends UnitTestCase
     {
         parent::setUp();
         $this->mockFactory = $this->getAccessibleMock(LockFactory::class, ['dummy']);
+
+        // backup global configuration
+        if (isset($GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'])) {
+            $this->strategiesConfigBackup = $GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'];
+        } else {
+            $this->strategiesConfigBackup = [];
+        }
+    }
+
+    protected function tearDown(): void
+    {
+        // restore global configuration
+        $GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'] = $this->strategiesConfigBackup;
+
+        parent::tearDown();
     }
 
     /**
@@ -67,7 +89,10 @@ class LockFactoryTest extends UnitTestCase
     public function getLockerReturnsExpectedClass()
     {
         $this->mockFactory->_set('lockingStrategy', [FileLockStrategy::class => true, DummyLock::class => true]);
-        $locker = $this->mockFactory->createLocker('id', LockingStrategyInterface::LOCK_CAPABILITY_EXCLUSIVE | LockingStrategyInterface::LOCK_CAPABILITY_SHARED);
+        $locker = $this->mockFactory->createLocker(
+            'id',
+            LockingStrategyInterface::LOCK_CAPABILITY_EXCLUSIVE | LockingStrategyInterface::LOCK_CAPABILITY_SHARED
+        );
         self::assertInstanceOf(FileLockStrategy::class, $locker);
     }
 
@@ -81,6 +106,25 @@ class LockFactoryTest extends UnitTestCase
         self::assertInstanceOf(DummyLock::class, $locker);
     }
 
+    /**
+     * @test
+     */
+    public function setPriorityGetLockerReturnsClassWithHighestPriority()
+    {
+        $lowestValue = min([
+            FileLockStrategy::DEFAULT_PRIORITY,
+            SimpleLockStrategy::DEFAULT_PRIORITY,
+            SemaphoreLockStrategy::DEFAULT_PRIORITY
+        ]) - 1;
+        $GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][FileLockStrategy::class]['priority'] = $lowestValue;
+        $GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][SemaphoreLockStrategy::class]['priority'] = $lowestValue;
+        $locker = $this->mockFactory->createLocker('id');
+        self::assertInstanceOf(SimpleLockStrategy::class, $locker);
+
+        unset($GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][FileLockStrategy::class]['priority']);
+        unset($GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][SemaphoreLockStrategy::class]['priority']);
+    }
+
     /**
      * @test
      */

typo3/sysext/core/Tests/Unit/Locking/SemaphoreLockStrategyTest.php

@@ -15,6 +15,7 @@ namespace TYPO3\CMS\Core\Tests\Unit\Locking;
  */
 
 use TYPO3\CMS\Core\Locking\SemaphoreLockStrategy;
+use TYPO3\CMS\Core\Locking\SimpleLockStrategy;
 use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
 
 /**
@@ -34,4 +35,23 @@ class SemaphoreLockStrategyTest extends UnitTestCase
         $lock->release();
         $lock->destroy();
     }
+
+    /**
+     * @test
+     */
+    public function getPriorityReturnsDefaultPriority()
+    {
+        self::assertEquals(SimpleLockStrategy::getPriority(), SimpleLockStrategy::DEFAULT_PRIORITY);
+    }
+
+    /**
+     * @test
+     */
+    public function setPriority()
+    {
+        $GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][\TYPO3\CMS\Core\Locking\SemaphoreLockStrategy::class]['priority'] = 10;
+
+        self::assertEquals(10, SemaphoreLockStrategy::getPriority());
+        unset($GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][\TYPO3\CMS\Core\Locking\SemaphoreLockStrategy::class]['priority']);
+    }
 }

typo3/sysext/core/Tests/Unit/Locking/SimpleLockStrategyTest.php

@@ -16,6 +16,7 @@ namespace TYPO3\CMS\Core\Tests\Unit\Locking;
 
 use PHPUnit\Framework\SkippedTestError;
 use TYPO3\CMS\Core\Core\Environment;
+use TYPO3\CMS\Core\Locking\SemaphoreLockStrategy;
 use TYPO3\CMS\Core\Locking\SimpleLockStrategy;
 use TYPO3\CMS\Core\Utility\GeneralUtility;
 use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
@@ -124,4 +125,23 @@ class SimpleLockStrategyTest extends UnitTestCase
         }
         self::assertTrue($fileExists);
     }
+
+    /**
+     * @test
+     */
+    public function getPriorityReturnsDefaultPriority()
+    {
+        self::assertEquals(SemaphoreLockStrategy::getPriority(), SemaphoreLockStrategy::DEFAULT_PRIORITY);
+    }
+
+    /**
+     * @test
+     */
+    public function setPriority()
+    {
+        $GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][\TYPO3\CMS\Core\Locking\SimpleLockStrategy::class]['priority'] = 10;
+
+        self::assertEquals(10, SimpleLockStrategy::getPriority());
+        unset($GLOBALS['TYPO3_CONF_VARS']['SYS']['locking']['strategies'][\TYPO3\CMS\Core\Locking\SimpleLockStrategy::class]['priority']);
+    }
 }