locker

application/Espo/Core/CronManager.php

@@ -42,6 +42,7 @@ use Espo\Core\{
     Utils\Cron\ScheduledJob as CronScheduledJob,
     Utils\Cron\Job as CronJob,
     ORM\EntityManager,
+    Utils\Cron\JobTask,
 };
 
 use Espo\Entities\Job as JobEntity;
@@ -196,7 +197,7 @@ class CronManager
     /**
      * Run a portion of pending jobs.
      */
-    public function processPendingJobs($queue = null, $limit = null, $poolDisabled = false, $noLock = false)
+    public function processPendingJobs($queue = null, $limit = null, bool $poolDisabled = false, bool $noLock = false)
     {
         if (is_null($limit)) {
             $limit = intval($this->config->get('jobMaxPortion', 0));
@@ -210,51 +211,17 @@ class CronManager
             $useProcessPool = false;
         }
 
+        $pool = null;
+
         if ($useProcessPool) {
-            $pool = \Spatie\Async\Pool::create()
+            $pool = AsyncPool::create()
                 ->autoload(getcwd() . '/vendor/autoload.php')
                 ->concurrency($this->config->get('jobPoolConcurrencyNumber'))
                 ->timeout($this->config->get('jobPeriodForActiveProcess'));
         }
 
         foreach ($pendingJobList as $job) {
-            $skip = false;
-            if (!$noLock) $this->lockJobTable();
-            if ($noLock || $this->getCronJobUtil()->isJobPending($job->id)) {
-                if ($job->get('scheduledJobId')) {
-                    if ($this->getCronJobUtil()->isScheduledJobRunning(
-                        $job->get('scheduledJobId'), $job->get('targetId'), $job->get('targetType'))
-                    ) {
-                        $skip = true;
-                    }
-                }
-            } else {
-                $skip = true;
-            }
-
-            if ($skip) {
-                if (!$noLock) $this->unlockTables();
-                continue;
-            }
-
-            $job->set('startedAt', date('Y-m-d H:i:s'));
-
-            if ($useProcessPool) {
-                $job->set('status', self::READY);
-            } else {
-                $job->set('status', self::RUNNING);
-                $job->set('pid', \Espo\Core\Utils\System::getPid());
-            }
-
-            $this->entityManager->saveEntity($job);
-            if (!$noLock) $this->unlockTables();
-
-            if ($useProcessPool) {
-                $task = new \Espo\Core\Utils\Cron\JobTask($job->id);
-                $pool->add($task);
-            } else {
-                $this->runJob($job);
-            }
+            $this->processPendingJob($job, $pool, $noLock);
         }
 
         if ($useProcessPool) {
@@ -262,14 +229,74 @@ class CronManager
         }
     }
 
-    protected function lockJobTable()
+    protected function processPendingJob(JobEntity $job, $pool = null, bool $noLock = false)
     {
-        $this->entityManager->getPDO()->query('LOCK TABLES `job` WRITE');
-    }
+        $useProcessPool = (bool) $pool;
 
-    protected function unlockTables()
-    {
-        $this->entityManager->getPDO()->query('UNLOCK TABLES');
+        $lockTable = (bool) $job->get('scheduledJobId') && !$noLock;
+
+        $skip = false;
+
+        if (!$noLock) {
+            if ($lockTable) {
+                // MySQL doesn't allow to lock non-existent rows. We resort to locking an entire table.
+                $this->entityManager->getLocker()->lockExclusive('Job');
+            } else {
+                $this->entityManager->getTransactionManager()->start();
+            }
+        }
+
+        if ($noLock || $this->getCronJobUtil()->isJobPending($job->id)) {
+            if ($job->get('scheduledJobId')) {
+                if ($this->getCronJobUtil()->isScheduledJobRunning(
+                    $job->get('scheduledJobId'), $job->get('targetId'), $job->get('targetType'))
+                ) {
+                    $skip = true;
+                }
+            }
+        } else {
+            $skip = true;
+        }
+
+        if ($skip) {
+            if (!$noLock) {
+                if ($lockTable) {
+                    $this->entityManager->getLocker()->rollback();
+                } else {
+                    $this->entityManager->getTransactionManager()->rollback();
+                }
+            }
+
+            return;
+        }
+
+        $job->set('startedAt', date('Y-m-d H:i:s'));
+
+        if ($useProcessPool) {
+            $job->set('status', self::READY);
+        } else {
+            $job->set('status', self::RUNNING);
+            $job->set('pid', System::getPid());
+        }
+
+        $this->entityManager->saveEntity($job);
+
+        if (!$noLock) {
+            if ($lockTable) {
+                $this->entityManager->getLocker()->commit();
+            } else {
+                $this->entityManager->getTransactionManager()->commit();
+            }
+        }
+
+        if ($useProcessPool) {
+            $task = new JobTask($job->id);
+            $pool->add($task);
+
+            return;
+        }
+
+        $this->runJob($job);
     }
 
     /**
@@ -292,7 +319,7 @@ class CronManager
         }
 
         $job->set('status', self::RUNNING);
-        $job->set('pid',System::getPid());
+        $job->set('pid', System::getPid());
         $this->entityManager->saveEntity($job);
 
         $this->runJob($job);

application/Espo/Core/Mail/Importer.php

@@ -326,12 +326,15 @@ class Importer
         }
 
         if (!$duplicate) {
-            $this->lockEmailTable();
+            $this->getEntityManager()->getLocker()->lockExclusive('Email');
+
             if ($duplicate = $this->findDuplicate($email)) {
-                $this->unlockTables();
+                $this->getEntityManager()->getLocker()->rollback();
+
                 if ($duplicate->get('status') != 'Being Imported') {
                     $duplicate = $this->getEntityManager()->getEntity('Email', $duplicate->id);
                     $this->processDuplicate($duplicate, $assignedUserId, $userIdList, $folderData, $teamsIdList);
+
                     return $duplicate;
                 }
             }
@@ -355,23 +358,26 @@ class Importer
                 'fromString' => $email->get('fromString'),
                 'replyToString' => $email->get('replyToString'),
             ]);
+
             $this->getEntityManager()->getRepository('Email')->fillAccount($duplicate);
 
             $this->processDuplicate($duplicate, $assignedUserId, $userIdList, $folderData, $teamsIdList);
+
             return $duplicate;
         }
 
         if (!$email->get('messageId')) {
             $email->setDummyMessageId();
         }
+
         $email->set('status', 'Being Imported');
 
         $this->getEntityManager()->saveEntity($email, [
             'skipAll' => true,
-            'keepNew' => true
+            'keepNew' => true,
         ]);
 
-        $this->unlockTables();
+        $this->getEntityManager()->getLocker()->commit();
 
         if ($parentFound) {
             $parentType = $email->get('parentType');
@@ -400,7 +406,7 @@ class Importer
             $attachment->set([
                 'relatedId' => $email->id,
                 'relatedType' => 'Email',
-                'field' => 'body'
+                'field' => 'body',
             ]);
             $this->getEntityManager()->saveEntity($attachment);
         }
@@ -408,21 +414,12 @@ class Importer
         return $email;
     }
 
-    protected function lockEmailTable()
-    {
-        $this->getEntityManager()->getPdo()->query('LOCK TABLES `email` WRITE');
-    }
-
-    protected function unlockTables()
-    {
-        $this->getEntityManager()->getPdo()->query('UNLOCK TABLES');
-    }
-
     protected function findParent(Email $email, $emailAddress)
     {
         $contact = $this->getEntityManager()->getRepository('Contact')->where([
             'emailAddress' => $emailAddress
         ])->findOne();
+
         if ($contact) {
             if (!$this->getConfig()->get('b2cMode')) {
                 if ($contact->get('accountId')) {
@@ -438,6 +435,7 @@ class Importer
             $account = $this->getEntityManager()->getRepository('Account')->where([
                 'emailAddress' => $emailAddress
             ])->findOne();
+
             if ($account) {
                 $email->set('parentType', 'Account');
                 $email->set('parentId', $account->id);
@@ -507,7 +505,7 @@ class Importer
                     $duplicate->setLinkMultipleColumn('users', 'folderId', $uId, $folderId);
                 } else {
                     $this->getEntityManager()->getRepository('Email')->updateRelation($duplicate, 'users', $uId, [
-                        'folderId' => $folderId
+                        'folderId' => $folderId,
                     ]);
                 }
             }
@@ -519,17 +517,17 @@ class Importer
 
         $this->getEntityManager()->getRepository('Email')->processLinkMultipleFieldSave($duplicate, 'users', [
             'skipLinkMultipleRemove' => true,
-            'skipLinkMultipleUpdate' => true
+            'skipLinkMultipleUpdate' => true,
         ]);
 
         $this->getEntityManager()->getRepository('Email')->processLinkMultipleFieldSave($duplicate, 'assignedUsers', [
             'skipLinkMultipleRemove' => true,
-            'skipLinkMultipleUpdate' => true
+            'skipLinkMultipleUpdate' => true,
         ]);
 
         if ($notificator = $this->getNotificator()) {
             $notificator->process($duplicate, [
-                'isBeingImported' => true
+                'isBeingImported' => true,
             ]);
         }
 
@@ -558,7 +556,7 @@ class Importer
                     'targetId' => $duplicate->id
                 ],
                 'executeAt' => $executeAt,
-                'queue' => 'q1'
+                'queue' => 'q1',
             ]);
             $this->getEntityManager()->saveEntity($job);
         }

application/Espo/Core/Utils/Cron/Job.php

@@ -75,12 +75,22 @@ class Job
         return $this->cronScheduledJob;
     }
 
-    public function isJobPending($id)
+    public function isJobPending(string $id) : bool
     {
-        return !!$this->getEntityManager()->getRepository('Job')->select(['id'])->where([
-            'id' => $id,
-            'status' => CronManager::PENDING
-        ])->findOne();
+        $job = $this->getEntityManager()
+            ->getRepository('Job')
+            ->select(['id', 'status'])
+            ->where([
+                'id' => $id,
+            ])
+            ->forUpdate()
+            ->findOne();
+
+        if (!$job) {
+            return false;
+        }
+
+        return $job->get('status') === CronManager::PENDING;
     }
 
     public function getPendingJobList($queue = null, $limit = 0)
@@ -113,17 +123,22 @@ class Job
         return $this->getEntityManager()->getRepository('Job')->find($selectParams);
     }
 
-    public function isScheduledJobRunning($scheduledJobId, $targetId = null, $targetType = null)
+    public function isScheduledJobRunning(string $scheduledJobId, ?string $targetId = null, ?string $targetType = null) : bool
     {
         $where = [
             'scheduledJobId' => $scheduledJobId,
             'status' => [CronManager::RUNNING, CronManager::READY],
         ];
+
         if ($targetId && $targetType) {
             $where['targetId'] = $targetId;
             $where['targetType'] = $targetType;
         }
-        return !!$this->getEntityManager()->getRepository('Job')->select(['id'])->where($where)->findOne();
+
+        return (booL) $this->getEntityManager()->getRepository('Job')
+            ->select(['id'])
+            ->where($where)
+            ->findOne();
     }
 
     public function getRunningScheduledJobIdList() : array

application/Espo/ORM/EntityManager.php

@@ -34,6 +34,7 @@ use Espo\ORM\{
     QueryComposer\QueryComposer,
     Repository\RepositoryFactory,
     Repository\Repository,
+    Locker\Locker,
 };
 
 use PDO;
@@ -70,6 +71,8 @@ class EntityManager
 
     protected $transactionManager;
 
+    protected $locker;
+
     protected $defaultMapperName = 'RDB';
 
     protected $driverPlatformMap = [
@@ -114,6 +117,8 @@ class EntityManager
         $this->collectionFactory = new CollectionFactory($this);
 
         $this->transactionManager = new TransactionManager($this->getPDO(), $this->queryComposer);
+
+        $this->initLocker();
     }
 
     protected function initQueryComposer()
@@ -126,12 +131,28 @@ class EntityManager
         }
 
         if (!$className || !class_exists($className)) {
-            throw new RuntimeException("Query composer {$name} could not be created.");
+            throw new RuntimeException("Query composer could not be created.");
         }
 
         $this->queryComposer = new $className($this->getPDO(), $this->entityFactory, $this->metadata);
     }
 
+    protected function initLocker()
+    {
+        $className = $this->params['lockerClassName'] ?? null;
+
+        if (!$className) {
+            $platform = $this->params['platform'];
+            $className = 'Espo\\ORM\\Locker\\' . ucfirst($platform) . 'Locker';
+        }
+
+        if (!$className || !class_exists($className)) {
+            throw new RuntimeException("Locker could not be created.");
+        }
+
+        $this->locker = new $className($this->getPDO(), $this->queryComposer, $this->transactionManager);
+    }
+
     /**
      * @todo Remove in v7.0.
      * @deprecated
@@ -151,6 +172,11 @@ class EntityManager
         return $this->transactionManager;
     }
 
+    public function getLocker() : Locker
+    {
+        return $this->locker;
+    }
+
     protected function getMapperClassName(string $name) : string
     {
         $className = null;

application/Espo/ORM/Locker/BaseLocker.php

@@ -0,0 +1,129 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2020 Yuri Kuznetsov, Taras Machyshyn, Oleksiy Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Locker;
+
+use Espo\ORM\{
+    TransactionManager,
+    QueryComposer\QueryComposer,
+    QueryParams\LockTableBuilder,
+};
+
+use PDO;
+use RuntimeException;
+
+abstract class BaseLocker implements Locker
+{
+    protected $pdo;
+    protected $queryComposer;
+    protected $transactionManager;
+
+    protected $isLocked = false;
+
+    public function __construct(PDO $pdo, QueryComposer $queryComposer, TransactionManager $transactionManager)
+    {
+        $this->pdo = $pdo;
+        $this->queryComposer = $queryComposer;
+        $this->transactionManager = $transactionManager;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function isLocked() : bool
+    {
+        return $this->isLocked;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function lockExclusive(string $entityType)
+    {
+        $this->isLocked = true;
+
+        $this->transactionManager->start();
+
+        $query = (new LockTableBuilder())
+            ->table($entityType)
+            ->inExclusiveMode()
+            ->build();
+
+        $sql = $this->queryComposer->compose($query);
+
+        $this->pdo->exec($sql);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function lockShare(string $entityType)
+    {
+        $this->isLocked = true;
+
+        $this->transactionManager->start();
+
+        $query = (new LockTableBuilder())
+            ->table($entityType)
+            ->inShareMode()
+            ->build();
+
+        $sql = $this->queryComposer->compose($query);
+
+        $this->pdo->exec($sql);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function commit()
+    {
+        if (!$this->isLocked) {
+            throw new RuntimeException("Can't commit, it was not locked.");
+        }
+
+        $this->transactionManager->commit();
+
+        $this->isLocked = false;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function rollback()
+    {
+        if (!$this->isLocked) {
+            throw new RuntimeException("Can't rollback, it was not locked.");
+        }
+
+        $this->transactionManager->rollback();
+
+        $this->isLocked = false;
+    }
+}

application/Espo/ORM/Locker/Locker.php

@@ -0,0 +1,62 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2020 Yuri Kuznetsov, Taras Machyshyn, Oleksiy Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Locker;
+
+/**
+ * Locks and unlocks tables.
+ * Wraps operations between lock and unlock into a transaction.
+ */
+interface Locker
+{
+    /**
+     * Whether any table has been locked.
+     */
+    public function isLocked();
+
+    /**
+     * Locks a table in an exclusive mode. Starts a transaction on first call.
+     */
+    public function lockExclusive(string $entityType);
+
+    /**
+     * Locks a table in a share mode. Starts a transaction on first call.
+     */
+    public function lockShare(string $entityType);
+
+    /**
+     * Commits changes and unlocks tables.
+     */
+    public function commit();
+
+    /**
+     * Rollbacks changes and unlocks tables.
+     */
+    public function rollback();
+}

application/Espo/ORM/Locker/MysqlLocker.php

@@ -0,0 +1,60 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2020 Yuri Kuznetsov, Taras Machyshyn, Oleksiy Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Locker;
+
+use RuntimeException;
+
+class MysqlLocker extends BaseLocker
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function commit()
+    {
+        parent::commit();
+
+        $sql = $this->queryComposer->composeUnlockTables();
+
+        $this->pdo->exec($sql);
+
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function rollback()
+    {
+        parent::rollback();
+
+        $sql = $this->queryComposer->composeUnlockTables();
+
+        $this->pdo->exec($sql);
+    }
+}

application/Espo/ORM/QueryComposer/BaseQueryComposer.php

@@ -42,6 +42,7 @@ use Espo\ORM\{
     QueryParams\Delete as DeleteQuery,
     QueryParams\Union as UnionQuery,
     QueryParams\Selecting as SelectingQuery,
+    QueryParams\LockTable as LockTableQuery,
 };
 
 use PDO;
@@ -208,28 +209,32 @@ abstract class BaseQueryComposer implements QueryComposer
             return $this->composeUnion($query);
         }
 
+        if ($query instanceof LockTableQuery) {
+            return $this->composeLockTable($query);
+        }
+
         throw new RuntimeException("ORM Query: Unknown query type passed.");
     }
 
-    public function composeCreateSavepoint(string $name) : string
+    public function composeCreateSavepoint(string $savepointName) : string
     {
-        $name = $this->sanitize($name);
+        $savepointName = $this->sanitize($savepointName);
 
-        return 'SAVEPOINT ' . $name;
+        return 'SAVEPOINT ' . $savepointName;
     }
 
-    public function composeReleaseSavepoint(string $name) : string
+    public function composeReleaseSavepoint(string $savepointName) : string
     {
-        $name = $this->sanitize($name);
+        $savepointName = $this->sanitize($savepointName);
 
-        return 'RELEASE SAVEPOINT ' . $name;
+        return 'RELEASE SAVEPOINT ' . $savepointName;
     }
 
-    public function composeRollbackToSavepoint(string $name) : string
+    public function composeRollbackToSavepoint(string $savepointName) : string
     {
-        $name = $this->sanitize($name);
+        $savepointName = $this->sanitize($savepointName);
 
-        return 'ROLLBACK TO SAVEPOINT ' . $name;
+        return 'ROLLBACK TO SAVEPOINT ' . $savepointName;
     }
 
     protected function composeSelecting(SelectingQuery $queryParams) : string
@@ -237,35 +242,35 @@ abstract class BaseQueryComposer implements QueryComposer
         return $this->compose($queryParams);
     }
 
-    protected function composeSelect(SelectQuery $queryParams) : string
+    public function composeSelect(SelectQuery $queryParams) : string
     {
         $params = $queryParams->getRawParams();
 
         return $this->createSelectQueryInternal($params);
     }
 
-    protected function composeUpdate(UpdateQuery $queryParams) : string
+    public function composeUpdate(UpdateQuery $queryParams) : string
     {
         $params = $queryParams->getRawParams();
 
         return $this->createUpdateQuery($params);
     }
 
-    protected function composeDelete(DeleteQuery $queryParams) : string
+    public function composeDelete(DeleteQuery $queryParams) : string
     {
         $params = $queryParams->getRawParams();
 
         return $this->createDeleteQuery($params);
     }
 
-    protected function composeInsert(InsertQuery $queryParams) : string
+    public function composeInsert(InsertQuery $queryParams) : string
     {
         $params = $queryParams->getRawParams();
 
         return $this->createInsertQuery($params);
     }
 
-    protected function composeUnion(UnionQuery $queryParams) : string
+    public function composeUnion(UnionQuery $queryParams) : string
     {
         $params = $queryParams->getRawParams();
 

application/Espo/ORM/QueryComposer/MysqlQueryComposer.php

@@ -29,8 +29,45 @@
 
 namespace Espo\ORM\QueryComposer;
 
+use Espo\ORM\{
+    QueryParams\LockTable as LockTableQuery,
+};
+
 class MysqlQueryComposer extends BaseQueryComposer
 {
+    public function composeLockTable(LockTableQuery $queryParams) : string
+    {
+        $params = $queryParams->getRawParams();
+
+        $table = $this->toDb($this->sanitize($params['table']));
+
+        $mode = $params['mode'];
+
+        if (empty($table)) {
+            throw new LogicException();
+        }
+
+        if (!in_array($mode, [LockTableQuery::MODE_SHARE, LockTableQuery::MODE_EXCLUSIVE])) {
+            throw new LogicException();
+        }
+
+        $sql = "LOCK TABLES `{$table}` ";
+
+        $modeMap = [
+            LockTableQuery::MODE_SHARE => 'READ',
+            LockTableQuery::MODE_EXCLUSIVE => 'WRITE',
+        ];
+
+        $sql .= $modeMap[$mode];
+
+        return $sql;
+    }
+
+    public function composeUnlockTables() : string
+    {
+        return "UNLOCK TABLES";
+    }
+
     protected function limit(string $sql, ?int $offset = null, ?int $limit = null) : string
     {
         if (!is_null($offset) && !is_null($limit)) {

application/Espo/ORM/QueryComposer/QueryComposer.php

@@ -31,6 +31,12 @@ namespace Espo\ORM\QueryComposer;
 
 use Espo\ORM\{
     QueryParams\Query as Query,
+    QueryParams\Select as SelectQuery,
+    QueryParams\Update as UpdateQuery,
+    QueryParams\Insert as InsertQuery,
+    QueryParams\Delete as DeleteQuery,
+    QueryParams\Union as UnionQuery,
+    QueryParams\LockTable as LockTableQuery,
 };
 
 interface QueryComposer
@@ -40,9 +46,21 @@ interface QueryComposer
      */
     public function compose(Query $query) : string;
 
-    public function composeCreateSavepoint(string $name) : string;
+    public function composeSelect(SelectQuery $query) : string;
 
-    public function composeReleaseSavepoint(string $name) : string;
+    public function composeUpdate(UpdateQuery $query) : string;
 
-    public function composeRollbackToSavepoint(string $name) : string;
+    public function composeDelete(DeleteQuery $query) : string;
+
+    public function composeInsert(InsertQuery $query) : string;
+
+    public function composeUnion(UnionQuery $query) : string;
+
+    public function composeLockTable(LockTableQuery $query) : string;
+
+    public function composeCreateSavepoint(string $savepointName) : string;
+
+    public function composeReleaseSavepoint(string $savepointName) : string;
+
+    public function composeRollbackToSavepoint(string $savepointName) : string;
 }

application/Espo/ORM/QueryParams/LockTable.php

@@ -0,0 +1,54 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2020 Yuri Kuznetsov, Taras Machyshyn, Oleksiy Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\QueryParams;
+
+use RuntimeException;
+
+/**
+ * LOCK TABLE parameters.
+ */
+class LockTable implements Query
+{
+    use BaseTrait;
+
+    const MODE_SHARE = 'SHARE';
+    const MODE_EXCLUSIVE = 'EXCLUSIVE';
+
+    protected function validateRawParams(array $params)
+    {
+        if (empty($params['table'])) {
+            throw new RuntimeException("LockTable params: No table specified.");
+        }
+
+        if (empty($params['mode'])) {
+            throw new RuntimeException("LockTable params: No mode specified.");
+        }
+    }
+}

application/Espo/ORM/QueryParams/LockTableBuilder.php

@@ -0,0 +1,85 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2020 Yuri Kuznetsov, Taras Machyshyn, Oleksiy Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\QueryParams;
+
+use InvalidArgumentException;
+
+class LockTableBuilder implements Builder
+{
+    use BaseBuilderTrait;
+
+    /**
+     * Build a LOCK TABLE query.
+     */
+    public function build() : LockTable
+    {
+        return LockTable::fromRaw($this->params);
+    }
+
+    /**
+     * Clone an existing query for a subsequent modifying and building.
+     */
+    public function clone(LockTable $query) : self
+    {
+        $this->cloneInternal($query);
+
+        return $this;
+    }
+
+    /**
+     * What entity type to lock.
+     */
+    public function table(string $entityType) : self
+    {
+        $this->params['table'] = $entityType;
+
+        return $this;
+    }
+
+    /**
+     * In SHARE mode.
+     */
+    public function inShareMode() : self
+    {
+        $this->params['mode'] = LockTable::MODE_SHARE;
+
+        return $this;
+    }
+
+    /**
+     * In EXCLUSIVE mode.
+     */
+    public function inExclusiveMode() : self
+    {
+        $this->params['mode'] = LockTable::MODE_EXCLUSIVE;
+
+        return $this;
+    }
+}

application/Espo/ORM/Repository/RDBRepository.php

@@ -46,8 +46,6 @@ class RDBRepository extends Repository
 {
     protected $mapper;
 
-    private $isTableLocked = false;
-
     protected $hookMediator;
 
     protected $transactionManager;
@@ -56,10 +54,8 @@ class RDBRepository extends Repository
         string $entityType, EntityManager $entityManager, EntityFactory $entityFactory, ?HookMediator $hookMediator = null
     ) {
         $this->entityType = $entityType;
-        $this->entityName = $entityType;
-
-        $this->entityFactory = $entityFactory;
         $this->entityManager = $entityManager;
+        $this->entityFactory = $entityFactory;
 
         $this->seed = $this->entityFactory->create($entityType);
 
@@ -757,35 +753,6 @@ class RDBRepository extends Repository
         return $this->entityManager->getPDO();
     }
 
-    /**
-     * @deprecated
-     * @todo Remove.
-     */
-    protected function lockTable()
-    {
-        $tableName = $this->entityManager->getQueryComposer()->toDb($this->entityType);
-
-        // @todo Use SELECT ... FOR UPDATE with transaction.
-        $this->getPDO()->query("LOCK TABLES `{$tableName}` WRITE");
-        $this->isTableLocked = true;
-    }
-
-    /**
-     * @deprecated
-     * @todo Remove.
-     */
-    protected function unlockTable()
-    {
-        // @todo Use SELECT ... FOR UPDATE with transaction.
-        $this->getPDO()->query("UNLOCK TABLES");
-        $this->isTableLocked = false;
-    }
-
-    protected function isTableLocked()
-    {
-        return $this->isTableLocked;
-    }
-
     protected function createSelectBuilder() : RDBSelectBuilder
     {
         $builder = new RDBSelectBuilder($this->entityManager, $this->entityType);

application/Espo/Repositories/User.php

@@ -87,14 +87,18 @@ class User extends \Espo\Core\Repositories\Database implements
                 throw new Error("Username can't be empty.");
             }
 
-            $this->lockTable();
+            $this->getEntityManager()->getLocker()->lockExclusive($this->entityType);
 
-            $user = $this->select(['id'])->where([
-                'userName' => $userName
-            ])->findOne();
+            $user = $this
+                ->select(['id'])
+                ->where([
+                    'userName' => $userName,
+                ])
+                ->findOne();
 
             if ($user) {
-                $this->unlockTable();
+                $this->getEntityManager()->getLocker()->rollback();
+
                 throw new Conflict(json_encode(['reason' => 'userNameExists']));
             }
         } else {
@@ -104,15 +108,19 @@ class User extends \Espo\Core\Repositories\Database implements
                     throw new Error("Username can't be empty.");
                 }
 
-                $this->lockTable();
+                $this->getEntityManager()->getLocker()->lockExclusive($this->entityType);
 
-                $user = $this->select(['id'])->where(array(
-                    'userName' => $userName,
-                    'id!=' => $entity->id
-                ))->findOne();
+                $user = $this
+                    ->select(['id'])
+                    ->where([
+                        'userName' => $userName,
+                        'id!=' => $entity->id,
+                    ])
+                    ->findOne();
 
                 if ($user) {
-                    $this->unlockTable();
+                    $this->getEntityManager()->getLocker()->rollback();
+
                     throw new Conflict(json_encode(['reason' => 'userNameExists']));
                 }
             }
@@ -121,8 +129,8 @@ class User extends \Espo\Core\Repositories\Database implements
 
     protected function afterSave(Entity $entity, array $options = [])
     {
-        if ($this->isTableLocked()) {
-            $this->unlockTable();
+        if ($this->getEntityManager()->getLocker()->isLocked()) {
+            $this->getEntityManager()->getLocker()->commit();
         }
 
         parent::afterSave($entity, $options);

tests/unit/Espo/ORM/EntityTest.php

@@ -27,6 +27,8 @@
  * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
  ************************************************************************/
 
+namespace tests\unit\Espo\ORM;
+
 use Espo\ORM\{
     DB\MysqlMapper,
     DB\Query\Mysql as Query,

tests/unit/Espo/ORM/MapperTest.php

@@ -27,6 +27,8 @@
  * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
  ************************************************************************/
 
+namespace tests\unit\Espo\ORM;
+
 use Espo\ORM\{
     Metadata,
     EntityManager,
@@ -47,6 +49,9 @@ use Espo\Entities\{
     Job,
 };
 
+use PDO;
+use PDOStatement;
+
 require_once 'tests/unit/testData/DB/Entities.php';
 
 class DBMapperTest extends \PHPUnit\Framework\TestCase

tests/unit/Espo/ORM/MetadataTest.php

@@ -27,6 +27,8 @@
  * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
  ************************************************************************/
 
+namespace tests\unit\Espo\ORM;
+
 use Espo\ORM\{
     Metadata,
 };

tests/unit/Espo/ORM/MysqlLockerTest.php

@@ -0,0 +1,130 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2020 Yuri Kuznetsov, Taras Machyshyn, Oleksiy Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace tests\unit\Espo\ORM;
+
+use Espo\ORM\{
+    TransactionManager,
+    QueryComposer\MysqlQueryComposer,
+    EntityFactory,
+    Metadata,
+    Locker\MysqlLocker,
+};
+
+use PDO;
+use PDOException;
+use RuntimeException;
+
+class MysqlLockerTest extends \PHPUnit\Framework\TestCase
+{
+    protected function setUp() : void
+    {
+        $this->pdo = $this->getMockBuilder(PDO::class)->disableOriginalConstructor()->getMock();
+
+        $entityFactory = $this->getMockBuilder(EntityFactory::class)->disableOriginalConstructor()->getMock();
+
+        $metadata = $this->getMockBuilder(Metadata::class)->disableOriginalConstructor()->getMock();
+
+        $this->transactionManager = $this->getMockBuilder(TransactionManager::class)->disableOriginalConstructor()->getMock();
+
+        $composer = new MysqlQueryComposer($this->pdo, $entityFactory, $metadata);
+
+        $this->locker = new MysqlLocker($this->pdo, $composer, $this->transactionManager);
+    }
+
+    public function testLockCommit()
+    {
+        $this->pdo
+            ->expects($this->at(0))
+            ->method('exec')
+            ->with('LOCK TABLES `account` WRITE');
+
+        $this->transactionManager
+            ->expects($this->at(0))
+            ->method('start');
+
+        $this->pdo
+            ->expects($this->at(1))
+            ->method('exec')
+            ->with('LOCK TABLES `contact` READ');
+
+        $this->transactionManager
+            ->expects($this->at(1))
+            ->method('commit');
+
+        $this->pdo
+            ->expects($this->at(2))
+            ->method('exec')
+            ->with('UNLOCK TABLES');
+
+        $this->locker->lockExclusive('Account');
+        $this->locker->lockShare('Contact');
+
+        $this->assertTrue($this->locker->isLocked());
+
+        $this->locker->commit();
+
+        $this->assertFalse($this->locker->isLocked());
+    }
+
+    public function testLockRollback()
+    {
+        $this->pdo
+            ->expects($this->at(0))
+            ->method('exec')
+            ->with('LOCK TABLES `account` WRITE');
+
+        $this->transactionManager
+            ->expects($this->at(0))
+            ->method('start');
+
+        $this->pdo
+            ->expects($this->at(1))
+            ->method('exec')
+            ->with('LOCK TABLES `contact` READ');
+
+        $this->transactionManager
+            ->expects($this->at(1))
+            ->method('rollback');
+
+        $this->pdo
+            ->expects($this->at(2))
+            ->method('exec')
+            ->with('UNLOCK TABLES');
+
+        $this->locker->lockExclusive('Account');
+        $this->locker->lockShare('Contact');
+
+        $this->assertTrue($this->locker->isLocked());
+
+        $this->locker->commit();
+
+        $this->assertFalse($this->locker->isLocked());
+    }
+}

tests/unit/Espo/ORM/MysqlQueryComposerTest.php

@@ -42,6 +42,7 @@ use Espo\ORM\QueryParams\{
     Insert,
     Update,
     Delete,
+    LockTableBuilder,
 };
 
 use Espo\Entities\{
@@ -2089,4 +2090,36 @@ class MysqlQueryComposerTest extends \PHPUnit\Framework\TestCase
 
         $this->assertEquals($expectedSql, $sql);
     }
+
+    public function testLockTableShare()
+    {
+        $builder = new LockTableBuilder();
+
+        $query = $builder
+            ->table('Account')
+            ->inShareMode()
+            ->build();
+
+        $sql = $this->query->compose($query);
+
+        $expectedSql = "LOCK TABLES `account` READ";
+
+        $this->assertEquals($expectedSql, $sql);
+    }
+
+    public function testLockTableExclusive()
+    {
+        $builder = new LockTableBuilder();
+
+        $query = $builder
+            ->table('Account')
+            ->inExclusiveMode()
+            ->build();
+
+        $sql = $this->query->compose($query);
+
+        $expectedSql = "LOCK TABLES `account` WRITE";
+
+        $this->assertEquals($expectedSql, $sql);
+    }
 }