From: Roland Haeder <roland@mxchange.org>
Date: Tue, 24 Mar 2015 20:10:57 +0000 (+0100)
Subject: Added task handler from 'hub' project.
X-Git-Url: https://git.mxchange.org/?p=core.git;a=commitdiff_plain;h=f481782bb05334d3e6fcab65560239b61086bfa1

Added task handler from 'hub' project.

Signed-off-by: Roland Häder <roland@mxchange.org>
---

diff --git a/inc/classes/main/handler/class_BaseHandler.php b/inc/classes/main/handler/class_BaseHandler.php
new file mode 100644
index 00000000..e9512006
--- /dev/null
+++ b/inc/classes/main/handler/class_BaseHandler.php
@@ -0,0 +1,78 @@
+<?php
+/**
+ * A general Handler
+ *
+ * @author		Roland Haeder <webmaster@shipsimu.org>
+ * @version		0.0.0
+ * @copyright	Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2015 Core Developer Team
+ * @license		GNU GPL 3.0 or any newer version
+ * @link		http://www.shipsimu.org
+ *
+ * This program 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.
+ *
+ * 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+class BaseHandler extends BaseFrameworkSystem implements HandleableDataSet {
+	/**
+	 * Handler name
+	 */
+	private $handlerName = 'invalid';
+
+	/**
+	 * Protected constructor
+	 *
+	 * @param	$className	Name of the class
+	 * @return	void
+	 */
+	protected function __construct ($className) {
+		// Call parent constructor
+		parent::__construct($className);
+	}
+
+	/**
+	 * Getter for handler name
+	 *
+	 * @return	$handlerName	Name of this handler
+	 */
+	public final function getHandlerName () {
+		return $this->handlerName;
+	}
+
+	/**
+	 * Setter for handler name
+	 *
+	 * @param	$handlerName	Name of this handler
+	 * @return	void
+	 */
+	protected final function setHandlerName ($handlerName) {
+		$this->handlerName = $handlerName;
+	}
+
+	/**
+	 * Adds all required elements from given array into data set instance
+	 *
+	 * @param	$dataSetInstance	An instance of a StoreableCriteria class
+	 * @param	$messageData		An array with all message data
+	 * @return	void
+	 * @todo	Rewrite this to use DHT
+	 */
+	public function addArrayToDataSet (StoreableCriteria $dataSetInstance, array $messageData) {
+		// Add some generic data all messageData arrays provide
+		/*
+		$dataSetInstance->addCriteria(NodeListDatabaseWrapper::DB_COLUMN_ANSWER_STATUS, $messageData[BaseXmlAnswerTemplateEngine::ANSWER_STATUS]);
+		$dataSetInstance->addCriteria(NodeListDatabaseWrapper::DB_COLUMN_MESSAGE_TYPE , $messageData[NetworkPackage::MESSAGE_ARRAY_TYPE]);
+		*/
+	}
+}
+
+// [EOF]
+?>
diff --git a/inc/classes/main/handler/tasks/.htaccess b/inc/classes/main/handler/tasks/.htaccess
new file mode 100644
index 00000000..3a428827
--- /dev/null
+++ b/inc/classes/main/handler/tasks/.htaccess
@@ -0,0 +1 @@
+Deny from all
diff --git a/inc/classes/main/handler/tasks/class_TaskHandler.php b/inc/classes/main/handler/tasks/class_TaskHandler.php
new file mode 100644
index 00000000..9fd650a6
--- /dev/null
+++ b/inc/classes/main/handler/tasks/class_TaskHandler.php
@@ -0,0 +1,335 @@
+<?php
+/**
+ * A Task handler
+ *
+ * @author		Roland Haeder <webmaster@shipsimu.org>
+ * @version		0.0.0
+ * @copyright	Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2015 Core Developer Team
+ * @license		GNU GPL 3.0 or any newer version
+ * @link		http://www.shipsimu.org
+ *
+ * This program 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.
+ *
+ * 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+class TaskHandler extends BaseHandler implements Registerable, HandleableTask {
+	// Exception constants
+	const EXCEPTION_TASK_IS_INVALID = 0xb00;
+
+	/**
+	 * Protected constructor
+	 *
+	 * @return	void
+	 */
+	protected function __construct () {
+		// Call parent constructor
+		parent::__construct(__CLASS__);
+
+		// Set handler name
+		$this->setHandlerName('task');
+	}
+
+	/**
+	 * Creates an instance of this class
+	 *
+	 * @return	$handlerInstance	An instance of a HandleableTask class
+	 */
+	public static final function createTaskHandler () {
+		// Get new instance
+		$handlerInstance = new TaskHandler();
+
+		// Output debug message
+		self::createDebugInstance(__CLASS__)->debugOutput('TASK-HANDLER[' . __METHOD__ . ':' . __LINE__ . ']: Initializing task handler.');
+
+		// Init the task list
+		$handlerInstance->setListInstance(ObjectFactory::createObjectByConfiguredName('task_list_class'));
+
+		// Get default instance
+		$handlerInstance->setIteratorInstance($handlerInstance->getListInstance()->getIterator());
+
+		// Init visitor instance for faster loop
+		$handlerInstance->setVisitorInstance(ObjectFactory::createObjectByConfiguredName('active_task_visitor_class'));
+
+		// Register the first (and generic) idle-loop task
+		$taskInstance = ObjectFactory::createObjectByConfiguredName('idle_task_class');
+		$handlerInstance->registerTask('idle_loop', $taskInstance);
+
+		// Output debug message
+		self::createDebugInstance(__CLASS__)->debugOutput('TASK-HANDLER[' . __METHOD__ . ':' . __LINE__ . ']: Task handler initialized.');
+
+		// Return the prepared instance
+		return $handlerInstance;
+	}
+
+	/**
+	 * Tries to execute the given task. If as task should not be started (yet)
+	 * or the interval time (see task_interval_delay) is not yet reached the
+	 * task is quietly skipped.
+	 *
+	 * @return	void
+	 * @throws	InvalidTaskException	If the current task is invalid
+	 */
+	private function executeCurrentTask () {
+		// Update no task by default
+		$updateTask = FALSE;
+
+		// Is the current task valid?
+		if (!$this->getListInstance()->getIterator()->valid()) {
+			// Not valid!
+			throw new InvalidTaskException($this, self::EXCEPTION_TASK_IS_INVALID);
+		} // END - if
+
+		// Get current task
+		$currentTask = $this->getListInstance()->getIterator()->current();
+
+		// Is the task not yet started?
+		if ($currentTask['task_started'] === FALSE) {
+			// Determine difference between current time and registration
+			$diff = ($this->getMilliTime() - $currentTask['task_registered']) * 1000;
+
+			// Should we start now?
+			if ($diff < $currentTask['task_startup_delay']) {
+				// Skip this silently
+				//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('TASK-HANDLER[' . __METHOD__ . ':' . __LINE__ . ']: Task ' . $currentTask['id'] . ' not started: diff=' . $diff . ',task_startup_delay=' . $currentTask['task_startup_delay']);
+				return;
+			} // END - if
+
+			// Launch the task and mark it as updated
+			$currentTask['task_started'] = TRUE;
+			$updateTask = TRUE;
+
+			// Debug message
+			self::createDebugInstance(__CLASS__)->debugOutput('TASK-HANDLER[' . __METHOD__ . ':' . __LINE__ . ']: Task ' . $currentTask['id'] . ' started with startup_delay=' . $currentTask['task_startup_delay'] . 'ms');
+		} // END - if
+
+		// Get time difference from interval delay
+		$diff = ($this->getMilliTime() - $currentTask['task_last_activity']) * 1000;
+
+		// Is the interval delay reached?
+		if ((($diff < $currentTask['task_interval_delay']) && ($currentTask['task_max_runs'] == 0)) || (($currentTask['task_total_runs'] == $currentTask['task_max_runs']) && ($currentTask['task_max_runs'] > 0))) {
+			// Should we update the task from startup?
+			if ($updateTask === TRUE) {
+				// Update the task before leaving
+				$this->updateTask($currentTask);
+			} // END - if
+
+			// Skip this silently
+			return;
+		} // END - if
+
+		// Set last activity
+		$currentTask['task_last_activity'] = $this->getMilliTime();
+
+		// Count this run
+		$currentTask['task_total_runs']++;
+
+		// Update the task
+		$this->updateTask($currentTask);
+
+		// And visit/run it
+		// @TODO Messurement can be added around this call
+		$currentTask['task_instance']->accept($this->getVisitorInstance());
+	}
+
+	/**
+	 * Updates given task by updating the underlaying list
+	 *
+	 * @param	$taskEntry	An array with a task
+	 * @return	void
+	 */
+	private function updateTask (array $taskEntry) {
+		// Get the key from current iteration
+		$key = $this->getListInstance()->getIterator()->key();
+
+		// Get the hash from key
+		$hash = $this->getListInstance()->getHash($key);
+
+		// Update the entry
+		$this->getListInstance()->updateCurrentEntryByHash($hash, $taskEntry);
+	}
+
+	/**
+	 * Unregisters the given task
+	 *
+	 * @param	$taskData	Data of the task
+	 * @return	void
+	 */
+	private function unregisterTask (array $taskData) {
+		// Debug output
+		self::createDebugInstance(__CLASS__)->debugOutput('TASK-HANDLER[' . __METHOD__ . ':' . __LINE__ . ']: Removing task ' . $taskData['id'] . ' from queue - CALLED!');
+
+		// Remove the entry
+		$this->getListInstance()->removeEntry('tasks', $taskData);
+
+		// Debug output
+		self::createDebugInstance(__CLASS__)->debugOutput('TASK-HANDLER[' . __METHOD__ . ':' . __LINE__ . ']: Removing task ' . $taskData['id'] . ' from queue - EXIT!');
+	 }
+
+	/**
+	 * Searches a task by given instance
+	 *
+	 * @param	$taskInstanc	An instanceof a Taskable class
+	 * @return	$taskName		Name of the task as used while registration
+	 */
+	public function searchTask (Taskable $taskInstance) {
+		// Default is an empty (not found) task name
+		$taskName = '';
+
+		// Get whole list
+		$taskList = $this->getListInstance()->getArrayFromList('tasks');
+
+		// Search all instances
+		foreach ($taskList as $currentTask) {
+			// Does it match given task instance?
+			if ($currentTask['task_instance']->equals($taskInstance)) {
+				// Found it
+				$taskName = $currentTask['id'];
+
+				// Abort here
+				break;
+			} // END - if
+		} // END - foreach
+
+		// Return found name
+		return $taskName;
+	}
+
+	/**
+	 * Registers a task with a task handler.
+	 *
+	 * @param	$taskName		A task name to register the task on
+	 * @param	$taskInstance	The instance we should register as a task
+	 * @return	void
+	 */
+	public function registerTask ($taskName, Visitable $taskInstance) {
+		// Create the entry
+		$taskEntry = array(
+			// Identifier for the generateHash() method
+			'id'                  => $taskName,
+			// Whether the task is started
+			'task_started'        => FALSE,
+			// Whether the task is paused (not yet implemented)
+			'task_paused'         => FALSE,
+			// Whether the task can be paused (not yet implemented)
+			'task_pauseable'      => TRUE,
+			// Timestamp of registration
+			'task_registered'     => $this->getMilliTime(),
+			// Last activity timestamp
+			'task_last_activity'  => 0,
+			// Total runs of this task
+			'task_total_runs'     => 0,
+			// Task instance itself
+			'task_instance'       => $taskInstance,
+			// Startup delay in milliseconds
+			'task_startup_delay'  => $this->getConfigInstance()->getConfigEntry('task_' . $taskName . '_startup_delay'),
+			// Interval time (delay) in milliseconds before this task is executed again
+			'task_interval_delay' => $this->getConfigInstance()->getConfigEntry('task_' . $taskName . '_interval_delay'),
+			// How often should this task run?
+			'task_max_runs'       => $this->getConfigInstance()->getConfigEntry('task_' . $taskName . '_max_runs'),
+		);
+
+		// Add the entry
+		$this->getListInstance()->addEntry('tasks', $taskEntry);
+
+		// Debug message
+		self::createDebugInstance(__CLASS__)->debugOutput('TASK-HANDLER[' . __METHOD__ . ':' . __LINE__ . ']: Task registered: taskName=' . $taskName .
+			' (taskInstance=' . $taskInstance->__toString() . ')' .
+			', startupDelay=' . $taskEntry['task_startup_delay'] . 'ms' .
+			', intervalDelay=' . $taskEntry['task_interval_delay'] . 'ms' .
+			', maxRuns=' . $taskEntry['task_max_runs'] . ' ...'
+		);
+	}
+
+	/**
+	 * Checks whether tasks are left including idle task
+	 *
+	 * @return	$tasksLeft	Whether there are tasks left to handle
+	 */
+	public function hasTasksLeft () {
+		// Do we have tasks there?
+		$tasksLeft = (($this->getListInstance() instanceof Listable) && ($this->getListInstance()->count() > 0));
+
+		// Return result
+		return $tasksLeft;
+	}
+
+	/**
+	 * Handles all tasks by checking if they should startup or if it is their
+	 * turn to run. You should use this method in a while() loop in conjuntion
+	 * with hasTasksLeft() so you can e.g. shutdown by adding a ShutdownTask
+	 * which will attempt to remove all tasks from the task handler.
+	 *
+	 * @return	void
+	 */
+	public function handleTasks () {
+		// Should we rewind?
+		if (!$this->getListInstance()->getIterator()->valid()) {
+			// Rewind to the beginning for next loop
+			$this->getListInstance()->getIterator()->rewind();
+		} // END - if
+
+		// Try to execute the task
+		$this->executeCurrentTask();
+
+		// Go to next entry
+		$this->getListInstance()->getIterator()->next();
+	}
+
+	/**
+	 * Shuts down all tasks and the task handler itself. This method should be
+	 * called from a corresponding filter class.
+	 * 
+	 * @return	void
+	 */
+	public function doShutdown () {
+		// Always rewind to the beginning for next loop
+		$this->getListInstance()->getIterator()->rewind();
+
+		// Debug message
+		self::createDebugInstance(__CLASS__)->debugOutput('TASK-HANDLER[' . __METHOD__ . ':' . __LINE__ . ']: Shutting down all ' . $this->getListInstance()->count() . ' tasks...');
+
+		// Remember all tasks that has been shutdown for removal
+		$tasks = array();
+
+		// Instance a visitor
+		$this->setVisitorInstance(ObjectFactory::createObjectByConfiguredName('shutdown_task_visitor_class'));
+
+		// Shutdown all tasks in once go
+		while ($this->getListInstance()->getIterator()->valid()) {
+			// Get current entry
+			$currentTask = $this->getListInstance()->getIterator()->current();
+
+			// Output debug message
+			self::createDebugInstance(__CLASS__)->debugOutput('TASK-HANDLER[' . __METHOD__ . ':' . __LINE__ . ']: Shutting down task ' . $currentTask['id'] . ' (taskInstance=' . $currentTask['task_instance']->__toString() . ') ...');
+
+			// Shutdown the task
+			$currentTask['task_instance']->accept($this->getVisitorInstance());
+
+			// Remember this task
+			array_push($tasks, $currentTask);
+
+			// Advance to next one
+			$this->getListInstance()->getIterator()->next();
+		} // END - while
+
+		// Debug message
+		self::createDebugInstance(__CLASS__)->debugOutput('TASK-HANDLER[' . __METHOD__ . ':' . __LINE__ . ']: Shutdown of all tasks completed.');
+
+		// Remove all tasks
+		foreach ($tasks as $entry) {
+			$this->unregisterTask($entry);
+		} // END - foreach
+	}
+}
+
+// [EOF]
+?>