Refactor Process for new paradigm

src/Core/Worker/Entity/Process.php

@@ -0,0 +1,46 @@
+<?php
+
+namespace Friendica\Core\Worker\Entity;
+
+use DateTime;
+use Friendica\BaseEntity;
+
+/**
+ * @property-read int $pid
+ * @property-read string $command
+ * @property-read DateTime $created
+ */
+class Process extends BaseEntity
+{
+	/** @var int */
+	protected $pid;
+	/** @var string */
+	protected $command;
+	/** @var DateTime */
+	protected $created;
+
+	/**
+	 * @param int       $pid
+	 * @param string    $command
+	 * @param DateTime $created
+	 */
+	public function __construct(int $pid, string $command, DateTime $created)
+	{
+		$this->pid     = $pid;
+		$this->command = $command;
+		$this->created = $created;
+	}
+
+	/**
+	 * Returns a new Process with the given PID
+	 *
+	 * @param int $pid
+	 *
+	 * @return $this
+	 * @throws \Exception
+	 */
+	public function withPid(int $pid): Process
+	{
+		return new static($pid, $this->command, new DateTime('now', new \DateTimeZone('URC')));
+	}
+}

src/Core/Worker/Exception/ProcessPersistenceException.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace Friendica\Core\Worker\Exception;
+
+use Throwable;
+
+class ProcessPersistenceException extends \RuntimeException
+{
+	public function __construct($message = "", Throwable $previous = null)
+	{
+		parent::__construct($message, 500, $previous);
+	}
+}

src/Core/Worker/Factory/Process.php

@@ -0,0 +1,38 @@
+<?php
+
+namespace Friendica\Core\Worker\Factory;
+
+use Friendica\BaseFactory;
+use Friendica\Capabilities\ICanCreateFromTableRow;
+use Friendica\Core\Worker\Entity;
+
+class Process extends BaseFactory implements ICanCreateFromTableRow
+{
+	public function createFromTableRow(array $row): Entity\Process
+	{
+		return new Entity\Process(
+			$row['pid'],
+			$row['command'],
+			new \DateTime($row['created'] ?? 'now', new \DateTimeZone('UTC'))
+		);
+	}
+
+	/**
+	 * Creates a new process entry for a given PID
+	 *
+	 * @param int $pid
+	 *
+	 * @return Entity\Process
+	 */
+	public function create(int $pid): Entity\Process
+	{
+		$trace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 1);
+
+		$command = basename($trace[0]['file']);
+
+		return $this->createFromTableRow([
+			'pid'     => $pid,
+			'command' => $command,
+		]);
+	}
+}

src/Core/Worker/Repository/Process.php

@@ -0,0 +1,118 @@
+<?php
+/**
+ * @copyright Copyright (C) 2010-2021, the Friendica project
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * 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
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace Friendica\Core\Worker\Repository;
+
+use Friendica\BaseRepository;
+use Friendica\Core\Worker\Exception\ProcessPersistenceException;
+use Friendica\Database\Database;
+use Friendica\Util\DateTimeFormat;
+use Friendica\Core\Worker\Factory;
+use Friendica\Core\Worker\Entity;
+use Psr\Log\LoggerInterface;
+
+/**
+ * functions for interacting with a process
+ */
+class Process extends BaseRepository
+{
+	protected static $table_name = 'process';
+
+	/** @var Factory\Process */
+	protected $factory;
+
+	public function __construct(Database $database, LoggerInterface $logger, Factory\Process $factory)
+	{
+		parent::__construct($database, $logger, $factory);
+	}
+
+	/**
+	 * Starts and Returns the process for a given PID
+	 *
+	 * @param int $pid
+	 *
+	 * @return Entity\Process
+	 */
+	public function create(int $pid): Entity\Process
+	{
+		// Cleanup inactive process
+		$this->deleteInactive();
+
+		try {
+			$this->db->transaction();
+
+			$newProcess = $this->factory->create($pid);
+
+			if (!$this->db->exists('process', ['pid' => $pid])) {
+				if (!$this->db->insert(static::$table_name, [
+					'pid' => $newProcess->pid,
+					'command' => $newProcess->command,
+					'created' => $newProcess->created->format(DateTimeFormat::MYSQL)
+				])) {
+					throw new ProcessPersistenceException(sprintf('The process with PID %s already exists.', $pid));
+				}
+			}
+
+			$result = $this->_selectOne(['pid' => $pid]);
+
+			$this->db->commit();
+
+			return $result;
+		} catch (\Exception $exception) {
+			throw new ProcessPersistenceException(sprintf('Cannot save process with PID %s.', $pid), $exception);
+		}
+	}
+
+	public function delete(Entity\Process $process)
+	{
+		try {
+			if (!$this->db->delete(static::$table_name, [
+				'pid' => $process->pid
+			])) {
+				throw new ProcessPersistenceException(sprintf('The process with PID %s doesn\'t exists.', $process->pi));
+			}
+		} catch (\Exception $exception) {
+			throw new ProcessPersistenceException(sprintf('Cannot delete process with PID %s.', $process->pid), $exception);
+		}
+	}
+
+	/**
+	 * Clean the process table of inactive physical processes
+	 */
+	private function deleteInactive()
+	{
+		$this->db->transaction();
+
+		try {
+			$processes = $this->db->select('process', ['pid']);
+			while ($process = $this->db->fetch($processes)) {
+				if (!posix_kill($process['pid'], 0)) {
+					$this->db->delete('process', ['pid' => $process['pid']]);
+				}
+			}
+			$this->db->close($processes);
+		} catch (\Exception $exception) {
+			throw new ProcessPersistenceException('Cannot delete inactive process', $exception);
+		} finally {
+			$this->db->commit();
+		}
+	}
+}