new default eTemplate request storate in EGroupware cache with an expiration time of 4 hours.

Benefit over old default is, that we get a short etemplate_exec_id giving better performance for ajax requests.
Drawback is currently poor garbadge collection only removing requests not used in 4 hours or which call egw_framework::window_close on server-side.
We can improve garbadge-collection by binding to window on(before)unload sending a (synchronious) request to server to remove concerned eT2 request.

etemplate/inc/class.etemplate.inc.php

@@ -51,11 +51,7 @@ class etemplate_new extends etemplate_widget_template
 		if ($name) $this->read($name,$template='default',$lang='default',$group=0,$version='',$load_via);
 
 		// generate new etemplate request object, if not already existing
-		if(!self::$request)
+		if(!isset(self::$request)) self::$request = etemplate_request::read();
-		{
-			self::$request = etemplate_request::read();
-			self::$request->content = array();
-		}
 	}
 
 	/**
@@ -294,6 +290,10 @@ class etemplate_new extends etemplate_widget_template
 			self::$response->generic('et2_validation_error', self::$validation_errors);
 			exit;
 		}
+
+		// tell request call to remove request, if it is not modified eg. by call to exec in callback
+		self::$request->remove_if_not_modified();
+
 		//error_log(__METHOD__."(,".array2string($content).')');
 		//error_log(' validated='.array2string($validated));
 		$content = ExecMethod(self::$request->method, self::complete_array_merge(self::$request->preserv, $validated));
@@ -346,6 +346,9 @@ class etemplate_new extends etemplate_widget_template
 		error_log(__METHOD__."(,".array2string($content).')');
 		error_log(' validated='.array2string($validated));
 
+		// tell request call to remove request, if it is not modified eg. by call to exec in callback
+		self::$request->remove_if_not_modified();
+
 		return ExecMethod(self::$request->method, self::complete_array_merge(self::$request->preserv, $validated));
 	}
 

etemplate/inc/class.etemplate_request.inc.php

@@ -7,7 +7,7 @@
  * @subpackage api
  * @link http://www.egroupware.org
  * @author Ralf Becker <RalfBecker@outdoor-training.de>
- * @copyright (c) 2007-13 by Ralf Becker <RalfBecker@outdoor-training.de>
+ * @copyright (c) 2007-14 by Ralf Becker <RalfBecker@outdoor-training.de>
  * @version $Id$
  */
 
@@ -64,6 +64,8 @@
  *	}
  *
  * For an example look in link_widget::ajax_search()
+ *
+ * @property-read boolean $data_modified true if data was modified and therefore needs saving
  */
 class etemplate_request
 {
@@ -79,6 +81,12 @@ class etemplate_request
 	 * @var boolean
 	 */
 	protected $data_modified=false;
+	/**
+	 * Flag that stored data should be removed by destructor, if not modified.
+	 *
+	 * @var boolean
+	 */
+	protected $remove_if_not_modified=false;
 	/**
 	 * mcrypt resource
 	 *
@@ -105,6 +113,9 @@ class etemplate_request
 	/**
 	 * Factory method to get a new request object or the one for an existing request
 	 *
+	 * New default is to use egw_cache to store requests and no longer request or
+	 * session documented below:
+	 *
 	 * If mcrypt AND gzcompress is available this factory method chooses etemplate_request,
 	 * which stores the request data encrypted in a hidden var directly in the form,
 	 * over etemplate_request_session, which stores the data in the session (and causing
@@ -117,13 +128,19 @@ class etemplate_request
 	{
 		if (is_null(self::$request_class))
 		{
+			// new default to use egw_cache to store requests
+			self::$request_class = 'etemplate_request_cache';
+			/* old default to use request if mcrypt and gzcompress are available and session if not
 			self::$request_class = check_load_extension('mcrypt') && function_exists('gzcompress') &&
 				self::init_crypt() ? __CLASS__ : 'etemplate_request_session';
+			 */
 		}
 		if (self::$request_class != __CLASS__)
 		{
-			return call_user_func(array(self::$request_class,'read'),$id);
+			$request = call_user_func(self::$request_class.'::read', $id);
 		}
+		else
+		{
 			$request = new etemplate_request();
 
 			if (!is_null($id))
@@ -150,10 +167,20 @@ class etemplate_request
 				if (!$request->data)
 				{
 					error_log(__METHOD__."() id not valid!");
-				return false;
+					$request = false;
 				}
 				//error_log(__METHOD__."() size of request = ".bytes($id));
 			}
+		}
+		if (!$request)	// eT2 request/session expired
+		{
+			// redirect to index-url of app
+			error_log(__METHOD__."('$id', ...) eT2 request not found --> redirect to index-url");
+			list($app) = explode('.', $_GET['menuaction']);
+			$index_url = isset($GLOBALS['egw_info']['apps'][$app]['index']) ?
+				'/index.php?menuaction='.$GLOBALS['egw_info']['apps'][$app]['index'] : '/'.$app.'/index.php';
+			egw_framework::redirect_link($index_url);
+		}
 		return $request;
 	}
 
@@ -174,14 +201,14 @@ class etemplate_request
 	 */
 	public function &id()
 	{
-		$id = serialize($this->data);
+		$data = serialize($this->data);
 
 		// compress the data if available
 		if (self::$compression_level && function_exists('gzcompress'))
 		{
 			//$len_uncompressed = bytes($id);
 			//$time = microtime(true);
-			$id = gzcompress($id,self::$compression_level);
+			$data = gzcompress($data, self::$compression_level);
 			//$time = number_format(1000.0 * (microtime(true) - $time),1);
 			//$len_compressed = bytes($id);
 			//error_log(__METHOD__."() compressed from $len_uncompressed to $len_compressed bytes in $time ms");
@@ -189,9 +216,9 @@ class etemplate_request
 		// encrypt the data if available
 		if (self::init_crypt())
 		{
-			$id = mcrypt_generic(self::$mcrypt,$id);
+			$data = mcrypt_generic(self::$mcrypt, $data);
 		}
-		$id = base64_encode($id);
+		$id = base64_encode($data);
 
 		//error_log(__METHOD__."() #$this->id: size of request = ".bytes($id));//.", id='$id'");
 		//self::debug();
@@ -293,6 +320,7 @@ class etemplate_request
 		if ($this->data[$var] !== $val)
 		{
 			$this->data[$var] = $val;
+			//error_log(__METHOD__."('$var', ...) data of id=$this->id changed ...");
 			$this->data_modified = true;
 		}
 	}
@@ -305,6 +333,8 @@ class etemplate_request
 	 */
 	public function &__get($var)
 	{
+		if ($var == 'data_modified') return $this->data_modified;
+
 		return $this->data[$var];
 	}
 
@@ -416,4 +446,14 @@ class etemplate_request
 			self::$mcrypt = null;
 		}
 	}
+
+	/**
+	 * Mark request as to destroy, if it does not get modified before destructor is called
+	 *
+	 * If that function is called, request is removed from storage, further modification will work!
+	 */
+	public function remove_if_not_modified()
+	{
+		$this->remove_if_not_modified = true;
+	}
 }

etemplate/inc/class.etemplate_request_cache.inc.php

@@ -0,0 +1,147 @@
+<?php
+/**
+ * eGroupWare - eTemplate request object storing the data in EGroupware instance cache
+ *
+ * @license http://opensource.org/licenses/gpl-license.php GPL - GNU General Public License
+ * @package etemplate
+ * @subpackage api
+ * @link http://www.egroupware.org
+ * @author Ralf Becker <RalfBecker@outdoor-training.de>
+ * @copyright (c) 2014 by Ralf Becker <RalfBecker@outdoor-training.de>
+ * @version $Id$
+ */
+
+/**
+ * Class to represent the persitent information stored on the server for each eTemplate request
+ *
+ * The information is stored in EGroupware tree cache with a given fixed expiration time.
+ * We use tree cache with install-id as part of key to not loose all requests, if admin
+ * clears instance cache (Admin >> Clear cache and register hooks)!
+ *
+ * To enable the use of this handler, you have to set (in etemplate/inc/class.etemplate_request.inc.php):
+ *
+ * 		etemplate_request::$request_class = 'etemplate_request_cache';
+ *
+ * The request object should be instancated only via the factory method etemplate_request::read($id=null)
+ *
+ * $request = etemplate_request::read();
+ *
+ * // add request data
+ *
+ * $id = $request->id();
+ *
+ * b) open or modify an existing request:
+ *
+ * if (!($request = etemplate_request::read($id)))
+ * {
+ * 		// request not found
+ * }
+ *
+ * Ajax requests can use this object to open the original request by using the id, they have to transmit back,
+ * and register further variables, modify the registered ones or delete them AND then update the id, if it changed:
+ *
+ *	if (($new_id = $request->id()) != $id)
+ *	{
+ *		$response->addAssign('etemplate_exec_id','value',$new_id);
+ *	}
+ *
+ * For an example look in link_widget::ajax_search()
+ */
+
+class etemplate_request_cache extends etemplate_request
+{
+	/**
+	 * Expiration time of 4 hours
+	 */
+	const EXPIRATION = 7200;
+
+	/**
+	 * request id
+	 *
+	 * @var string
+	 */
+	protected $id;
+
+	/**
+	 * Private constructor to force the instancation of this class only via it's static factory method read
+	 *
+	 * @param string $_id
+	 */
+	private function __construct($_id=null)
+	{
+		$this->id = $_id ? $_id : self::request_id();
+		//error_log(__METHOD__."($_id) this->id=$this->id");
+	}
+
+	/**
+	 * return the id of this request
+	 *
+	 * @return string
+	 */
+	public function id()
+	{
+		//error_log(__METHOD__."() id=$this->id");
+		return $this->id;
+	}
+
+	/**
+	 * Factory method to get a new request object or the one for an existing request
+	 *
+	 * @param string $id=null
+	 * @return etemplate_request|boolean the object or false if $id is not found
+	 */
+	static function read($id=null)
+	{
+		$request = new etemplate_request_cache($id);
+
+		if (!is_null($id))
+		{
+			//error_log(__METHOD__."() reading $id");
+			if (!($request->data = egw_cache::getTree($GLOBALS['egw_info']['server']['install_id'].'_etemplate', $id)))
+			{
+				error_log("Error reading etemplate request data for id=$id!");
+				return false;
+			}
+		}
+		//error_log(__METHOD__."(id=$id) returning ".array2string($request));
+		return $request;
+	}
+
+	/**
+	 * creates a new unique request-id
+	 *
+	 * @return string
+	 */
+	static function request_id()
+	{
+		return uniqid($GLOBALS['egw_info']['flags']['currentapp'].'_'.$GLOBALS['egw_info']['user']['account_lid'].'_',true);
+	}
+
+	/**
+	 * saves content,readonlys,template-keys, ... via eGW's appsession function
+	 *
+	 * As a user may open several windows with the same content/template wie generate a location-id from microtime
+	 * which is used as location for request to descriminate between the different windows. This location-id
+	 * is then saved as a hidden-var in the form. The above mentions session-id has nothing to do / is different
+	 * from the session-id which is constant for all windows opened in one session.
+	 */
+	function __destruct()
+	{
+		if ($this->remove_if_not_modified && !$this->data_modified && isset($this->data['last_saved']))
+		{
+			//error_log(__METHOD__."() destroying $this->id");
+			egw_cache::unsetTree($GLOBALS['egw_info']['server']['install_id'].'_etemplate', $this->id);
+		}
+		elseif (($this->data_modified ||
+			// if half of expiration time is over, save it anyway, to restart expiration time
+			isset($this->data['last_saved']) && (time()-$this->data['last_saved']) > self::EXPIRATION/2))
+		{
+			//error_log(__METHOD__."() saving $this->id");
+			$this->data['last_saved'] = time();
+			if (!egw_cache::setTree($GLOBALS['egw_info']['server']['install_id'].'_etemplate', $this->id, $this->data, self::EXPIRATION))
+			{
+				error_log("Error storing etemplate request data for id=$this->id!");
+			}
+		}
+	}
+}

etemplate/inc/class.etemplate_request_files.inc.php

@@ -7,7 +7,7 @@
  * @subpackage api
  * @link http://www.egroupware.org
  * @author Ralf Becker <RalfBecker@outdoor-training.de>
- * @copyright (c) 2009 by Ralf Becker <RalfBecker@outdoor-training.de>
+ * @copyright (c) 2009-14 by Ralf Becker <RalfBecker@outdoor-training.de>
  * @version $Id$
  */
 
@@ -139,7 +139,13 @@ class etemplate_request_files extends etemplate_request
 	 */
 	function __destruct()
 	{
-		if (!file_put_contents($filename = self::$directory.'/'.$this->id,serialize($this->data)))
+		if ($this->remove_if_not_modified && !$this->data_modified)
+		{
+			//error_log(__METHOD__."() destroying $this->id");
+			@unlink(self::$directory.'/'.$this->id);
+		}
+		elseif (!$this->destroyed && $this->data_modified &&
+			!file_put_contents($filename = self::$directory.'/'.$this->id,serialize($this->data)))
 		{
 			error_log("Error opening '$filename' to store the etemplate request data!");
 		}

etemplate/inc/class.etemplate_request_session.inc.php

@@ -7,7 +7,7 @@
  * @subpackage api
  * @link http://www.egroupware.org
  * @author Ralf Becker <RalfBecker@outdoor-training.de>
- * @copyright (c) 2007-9 by Ralf Becker <RalfBecker@outdoor-training.de>
+ * @copyright (c) 2007-14 by Ralf Becker <RalfBecker@outdoor-training.de>
  * @version $Id$
  */
 
@@ -119,8 +119,15 @@ class etemplate_request_session extends etemplate_request
 	 */
 	function __destruct()
 	{
-		if ($this->data_modified) $GLOBALS['egw']->session->appsession($this->id,'etemplate',$this->data);
+		if ($this->remove_if_not_modified && !$this->data_modified)
-
+		{
+			//error_log(__METHOD__."() destroying $this->id");
+			egw_cache::unsetSession('etemplate', $this->id);
+		}
+		elseif (!$this->destroyed && $this->data_modified)
+		{
+			egw_cache::setSession('etemplate', $this->id, $this->data);
+		}
 		if (!$this->garbage_collection_done)
 		{
 			$this->_php4_request_garbage_collection();