N°6901 - Enable tracking of iTop active sessions (monitoring) (#568)

Co-authored-by: Molkobain <lajarige.guillaume@free.fr>
Co-authored-by: Romain Quetiez <romain.quetiez@combodo.com>

application/menunode.class.inc.php

@@ -103,7 +103,7 @@ class ApplicationMenu
 	{
 		self::$sFavoriteSiloQuery = $sOQL;
 	}
-	
+
 	/**
 	 * Get the query used to limit the list of displayed organizations in the drop-down menu
 	 * @return string The OQL query returning a list of Organization objects
@@ -536,7 +536,7 @@ EOF
 
 		return -1;
 	}
-	
+
 	/**
 	 * Retrieves the currently active menu (if any, otherwise the first menu is the default)
 	 * @return string The Id of the currently active menu
@@ -544,7 +544,7 @@ EOF
 	public static function GetActiveNodeId()
 	{
 		$oAppContext = new ApplicationContext();
-		$sMenuId = $oAppContext->GetCurrentValue('menu', null);		
+		$sMenuId = $oAppContext->GetCurrentValue('menu', null);
 		if ($sMenuId  === null)
 		{
 			$sMenuId = self::GetDefaultMenuId();
@@ -654,7 +654,7 @@ abstract class MenuNode
 
 	/**
 	 * Stimulus to check: if the user can 'apply' this stimulus, then she/he can see this menu
-	 */	
+	 */
 	protected $m_aEnableStimuli;
 
 	/**
@@ -814,7 +814,7 @@ abstract class MenuNode
 	{
 		return false;
 	}
-	
+
 	/**
 	 * Add a limiting display condition for the same menu node. The conditions will be combined with a AND
 	 * @param $oMenuNode MenuNode Another definition of the same menu node, with potentially different access restriction
@@ -987,7 +987,7 @@ class TemplateMenuNode extends MenuNode
 	 * @var string
 	 */
 	protected $sTemplateFile;
-	
+
 	/**
 	 * Create a menu item based on a custom template and inserts it into the application's main menu
 	 * @param string $sMenuId Unique identifier of the menu (used to identify the menu for bookmarking, and for getting the labels from the dictionary)
@@ -1058,7 +1058,7 @@ class OQLMenuNode extends MenuNode
 	 * @var bool|null
 	 */
 	protected $bSearchFormOpen;
-	
+
 	/**
 	 * Extra parameters to be passed to the display block to fine tune its appearence
 	 */
@@ -1091,7 +1091,7 @@ class OQLMenuNode extends MenuNode
 		// Enhancement: we could set as the "enable" condition that the user has enough rights to "read" the objects
 		// of the class specified by the OQL...
 	}
-	
+
 	/**
 	 * Set some extra parameters to be passed to the display block to fine tune its appearence
 	 * @param array $aParams paramCode => value. See DisplayBlock::GetDisplay for the meaning of the parameters
@@ -1111,7 +1111,7 @@ class OQLMenuNode extends MenuNode
 	 */
 	public function RenderContent(WebPage $oPage, $aExtraParams = array())
 	{
-		ContextTag::AddContext(ContextTag::TAG_OBJECT_SEARCH);
+		$oTag = new ContextTag(ContextTag::TAG_OBJECT_SEARCH);
 		ApplicationMenu::CheckMenuIdEnabled($this->GetMenuId());
 		OQLMenuNode::RenderOQLSearch
 		(
@@ -1120,7 +1120,7 @@ class OQLMenuNode extends MenuNode
 			'Menu_'.$this->GetMenuId(),
 			$this->bSearch, // Search pane
 			$this->bSearchFormOpen, // Search open
-			$oPage, 
+			$oPage,
 			array_merge($this->m_aParams, $aExtraParams),
 			true
 		);
@@ -1354,10 +1354,10 @@ class NewObjectMenuNode extends MenuNode
 	{
 		// Enable this menu, only if the current user has enough rights to create such an object, or an object of
 		// any child class
-	
+
 		$aSubClasses = MetaModel::EnumChildClasses($this->sClass, ENUM_CHILD_CLASSES_ALL); // Including the specified class itself
 		$bActionIsAllowed = false;
-	
+
 		foreach($aSubClasses as $sCandidateClass)
 		{
 			if (!MetaModel::IsAbstract($sCandidateClass) && (UserRights::IsActionAllowed($sCandidateClass, UR_ACTION_MODIFY) == UR_ALLOWED_YES))
@@ -1366,7 +1366,7 @@ class NewObjectMenuNode extends MenuNode
 				break; // Enough for now
 			}
 		}
-		return $bActionIsAllowed;		
+		return $bActionIsAllowed;
 	}
 
 	/**
@@ -1508,7 +1508,7 @@ class DashboardMenuNode extends MenuNode
 			throw new Exception("Error: failed to load dashboard file: '{$this->sDashboardFile}'");
 		}
 	}
-	
+
 }
 
 /**
@@ -1549,7 +1549,7 @@ class ShortcutContainerMenuNode extends MenuNode
 			$sName = $this->GetMenuId().'_'.$oShortcut->GetKey();
 			new ShortcutMenuNode($sName, $oShortcut, $this->GetIndex(), $fRank++);
 		}
-	
+
 		// Complete the tree
 		//
 		parent::PopulateChildMenus();

core/cmdbsource.class.inc.php

@@ -3,7 +3,7 @@
 //
 //   This file is part of iTop.
 //
-//   iTop is free software; you can redistribute it and/or modify	
+//   iTop 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.
@@ -380,7 +380,7 @@ class CMDBSource
 	public static function GetDBVendor()
 	{
 		$sDBVendor = static::ENUM_DB_VENDOR_MYSQL;
-		
+
 		$sVersionComment = static::GetServerVariable('version') .  ' - ' . static::GetServerVariable('version_comment');
 		if(preg_match('/mariadb/i', $sVersionComment) === 1)
 		{
@@ -390,7 +390,7 @@ class CMDBSource
 		{
 			$sDBVendor = static::ENUM_DB_VENDOR_PERCONA;
 		}
-		
+
 		return $sDBVendor;
 	}
 
@@ -934,7 +934,7 @@ class CMDBSource
 		{
 			throw new MySQLException('Failed to issue SQL query', array('query' => $sSql));
 		}
-				
+
 		while ($aRow = $oResult->fetch_array($iMode))
 		{
 			$aData[] = $aRow;
@@ -1088,7 +1088,7 @@ class CMDBSource
 		if (!array_key_exists($iKey, $aTableInfo["Fields"])) return false;
 		$aFieldData = $aTableInfo["Fields"][$iKey];
 		if (!array_key_exists("Key", $aFieldData)) return false;
-		return ($aFieldData["Key"] == "PRI"); 
+		return ($aFieldData["Key"] == "PRI");
 	}
 
 	public static function IsAutoIncrement($sTable, $sField)
@@ -1099,7 +1099,7 @@ class CMDBSource
 		$aFieldData = $aTableInfo["Fields"][$sField];
 		if (!array_key_exists("Extra", $aFieldData)) return false;
 		//MyHelpers::debug_breakpoint($aFieldData);
-		return (strstr($aFieldData["Extra"], "auto_increment")); 
+		return (strstr($aFieldData["Extra"], "auto_increment"));
 	}
 
 	public static function IsField($sTable, $sField)
@@ -1366,13 +1366,13 @@ class CMDBSource
 	public static function GetTableFieldsList($sTable)
 	{
 		assert(!empty($sTable));
-		
+
 		$aTableInfo = self::GetTableInfo($sTable);
 		if (empty($aTableInfo)) return array(); // #@# or an error ?
 
 		return array_keys($aTableInfo["Fields"]);
 	}
-	
+
 	// Cache the information about existing tables, and their fields
 	private static $m_aTablesInfo = array();
 	private static function _TablesInfoCacheReset($sTableName = null)
@@ -1505,7 +1505,7 @@ class CMDBSource
 		{
 			throw new MySQLException('Failed to issue SQL query', array('query' => $sSql));
 		}
-		
+
 		$aRows = array();
 		while ($aRow = $oResult->fetch_array(MYSQLI_ASSOC))
 		{
@@ -1514,7 +1514,7 @@ class CMDBSource
 		$oResult->free();
 		return $aRows;
 	}
-	
+
 	/**
 	 * Returns the value of the specified server variable
 	 * @param string $sVarName Name of the server variable
@@ -1530,7 +1530,7 @@ class CMDBSource
 	/**
 	 * Returns the privileges of the current user
 	 * @return string privileges in a raw format
-	 */	   	
+	 */
 	public static function GetRawPrivileges()
 	{
 		try
@@ -1556,8 +1556,8 @@ class CMDBSource
 
 	/**
 	 * Determine the slave status of the server
-	 * @return bool true if the server is slave 
-	 */	   	
+	 * @return bool true if the server is slave
+	 */
 	public static function IsSlaveServer()
 	{
 		try

core/config.class.inc.php

@@ -1193,6 +1193,30 @@ class Config
 			'source_of_value' => '',
 			'show_in_conf_sample' => false,
 		],
+		'sessions_tracking.enabled' => [
+			'type' => 'bool',
+			'description' => 'Whether or not the whole mechanism to track active sessions is enabled. See PHP session.gc_maxlifetime setting to configure session expiration.',
+			'default' => false,
+			'value' => '',
+			'source_of_value' => '',
+			'show_in_conf_sample' => false,
+		],
+		'sessions_tracking.gc_threshold' => [
+			'type' => 'integer',
+			'description'         => 'fallback in case cron is not active: probability in percent that session files are cleanup during any itop request (100 means always)',
+			'default'             => 1,
+			'value' => '',
+			'source_of_value' => '',
+			'show_in_conf_sample' => false,
+		],
+		'sessions_tracking.gc_duration_in_seconds' => [
+			'type' => 'integer',
+			'description' => 'fallback in case cron is not active: when a cleanup is triggered cleanup duration will not exceed this duration (in seconds).',
+			'default' => 1,
+			'value' => '',
+			'source_of_value' => '',
+			'show_in_conf_sample' => false,
+		],
 		'transaction_storage' => [
 			'type' => 'string',
 			'description' => 'The type of mechanism to use for storing the unique identifiers for transactions (Session|File).',

core/log.class.inc.php

@@ -3,7 +3,7 @@
 //
 //   This file is part of iTop.
 //
-//   iTop is free software; you can redistribute it and/or modify	
+//   iTop 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.
@@ -576,6 +576,11 @@ class LogChannels
 	public const DATATABLE = 'Datatable';
 
 	public const DEADLOCK = 'DeadLock';
+	/**
+	 * @var string Everything related to PHP sessions tracking
+	 * @since 3.1.1 3.2.0 N°6901
+	 */
+	public const SESSIONTRACKER = 'SessionTracker';
 
 	/**
 	 * @var string Everything related to the datamodel CRUD

lib/composer/autoload_classmap.php

@@ -473,6 +473,8 @@ return array(
     'Combodo\\iTop\\Service\\TemporaryObjects\\TemporaryObjectManager' => $baseDir . '/sources/Service/TemporaryObjects/TemporaryObjectManager.php',
     'Combodo\\iTop\\Service\\TemporaryObjects\\TemporaryObjectRepository' => $baseDir . '/sources/Service/TemporaryObjects/TemporaryObjectRepository.php',
     'Combodo\\iTop\\Service\\TemporaryObjects\\TemporaryObjectsEvents' => $baseDir . '/sources/Service/TemporaryObjects/TemporaryObjectsEvents.php',
+    'Combodo\\iTop\\SessionTracker\\SessionGC' => $baseDir . '/sources/SessionTracker/SessionGC.php',
+    'Combodo\\iTop\\SessionTracker\\SessionHandler' => $baseDir . '/sources/SessionTracker/SessionHandler.php',
     'CompileCSSService' => $baseDir . '/application/compilecssservice.class.inc.php',
     'Composer\\InstalledVersions' => $vendorDir . '/composer/InstalledVersions.php',
     'Config' => $baseDir . '/core/config.class.inc.php',

lib/composer/autoload_static.php

@@ -837,6 +837,8 @@ class ComposerStaticInit7f81b4a2a468a061c306af5e447a9a9f
         'Combodo\\iTop\\Service\\TemporaryObjects\\TemporaryObjectManager' => __DIR__ . '/../..' . '/sources/Service/TemporaryObjects/TemporaryObjectManager.php',
         'Combodo\\iTop\\Service\\TemporaryObjects\\TemporaryObjectRepository' => __DIR__ . '/../..' . '/sources/Service/TemporaryObjects/TemporaryObjectRepository.php',
         'Combodo\\iTop\\Service\\TemporaryObjects\\TemporaryObjectsEvents' => __DIR__ . '/../..' . '/sources/Service/TemporaryObjects/TemporaryObjectsEvents.php',
+        'Combodo\\iTop\\SessionTracker\\SessionGC' => __DIR__ . '/../..' . '/sources/SessionTracker/SessionGC.php',
+        'Combodo\\iTop\\SessionTracker\\SessionHandler' => __DIR__ . '/../..' . '/sources/SessionTracker/SessionHandler.php',
         'CompileCSSService' => __DIR__ . '/../..' . '/application/compilecssservice.class.inc.php',
         'Composer\\InstalledVersions' => __DIR__ . '/..' . '/composer/InstalledVersions.php',
         'Config' => __DIR__ . '/../..' . '/core/config.class.inc.php',

pages/ajax.render.php

@@ -68,7 +68,7 @@ try
 			break;
 
 		default:
-			ContextTag::AddContext(ContextTag::TAG_CONSOLE);
+			$oTag = new ContextTag(ContextTag::TAG_CONSOLE);
 	}
 
 	// First check if we can redirect the route to a dedicated controller

sources/Application/Helper/Session.php

@@ -7,6 +7,7 @@
 
 namespace Combodo\iTop\Application\Helper;
 
+use Combodo\iTop\SessionTracker\SessionHandler;
 use utils;
 
 /**
@@ -34,6 +35,7 @@ class Session
 		}
 
 		if (!self::$bIsInitialized) {
+			SessionHandler::session_set_save_handler();
 			session_name('itop-'.md5(APPROOT));
 		}
 
@@ -214,4 +216,4 @@ class Session
 
 		return utils::IsModeCLI();
 	}
-}
+}

sources/SessionTracker/SessionGC.php

@@ -0,0 +1,32 @@
+<?php
+
+namespace Combodo\iTop\SessionTracker;
+
+/**
+ * Class SessionGC
+ *
+ * @author Olivier Dain <olivier.dain@combodo.com>
+ * @package Combodo\iTop\SessionTracker
+ * @since 3.1.1 3.2.0 N°6901
+ */
+class SessionGC implements \iBackgroundProcess
+{
+	/**
+	 * @inheritDoc
+	 */
+	public function GetPeriodicity()
+	{
+		return 60 * 1; // seconds
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function Process($iTimeLimit)
+	{
+		$iMaxLifetime = ini_get('session.gc_maxlifetime') ?? 1440;
+		$oSessionHandler = new SessionHandler();
+		$iProcessed = $oSessionHandler->gc_with_time_limit($iMaxLifetime, $iTimeLimit);
+		return "processed $iProcessed tasks";
+	}
+}

sources/SessionTracker/SessionHandler.php

@@ -0,0 +1,240 @@
+<?php
+
+namespace Combodo\iTop\SessionTracker;
+
+use Combodo\iTop\Application\Helper\Session;
+use ContextTag;
+use Exception;
+use IssueLog;
+use ReturnTypeWillChange;
+use UserRights;
+use utils;
+
+/**
+ * Class SessionHandler:
+ * defaut PHP SessionHandler already relies on files that are accessible by iTop.
+ * this new iTop SessionHandler creates additional session files that are located under iTop folders.
+ * these new session files are meant to monitor the application and contain additional data:
+ * - current user id
+ * - context
+ * - login_mode
+ * - session creation timestamp
+ *
+ * @author Olivier Dain <olivier.dain@combodo.com>
+ * @package Combodo\iTop\SessionTracker
+ * @since 3.1.1 3.2.0 N°6901
+ */
+class SessionHandler extends \SessionHandler
+{
+	/**
+	 * @param string $session_id
+	 *
+	 * @return bool
+	 */
+	#[ReturnTypeWillChange]
+	public function destroy($session_id) : bool
+	{
+		IssueLog::Debug("Destroy PHP session", \LogChannels::SESSIONTRACKER, [
+			'session_id' => $session_id,
+		]);
+		$bRes = parent::destroy($session_id);
+
+		if ($bRes) {
+			$this->unlink_session_file($session_id);
+		}
+
+		return $bRes;
+	}
+
+	/**
+	 * @param int $max_lifetime
+	 */
+	#[ReturnTypeWillChange]
+	public function gc($max_lifetime) : bool
+	{
+		IssueLog::Debug("Run PHP sessions garbage collector", \LogChannels::SESSIONTRACKER, [
+			'max_lifetime' => $max_lifetime,
+		]);
+		$iRes = parent::gc($max_lifetime);
+		$this->gc_with_time_limit($max_lifetime);
+		return $iRes;
+	}
+
+	/**
+	 * @param string $save_path
+	 * @param string $session_name
+	 */
+	#[ReturnTypeWillChange]
+	public function open($save_path, $session_name) : bool
+	{
+		$bRes = parent::open($save_path, $session_name);
+
+		$session_id = session_id();
+		IssueLog::Debug("Open PHP session", \LogChannels::SESSIONTRACKER, [
+			'session_id' => $session_id,
+		]);
+
+		if ($bRes) {
+			$this->touch_session_file($session_id);
+		}
+
+		return $bRes;
+	}
+
+	/**
+	 * @param string $session_id
+	 * @param string $data
+	 *
+	 * @return bool
+	 */
+	#[ReturnTypeWillChange]
+	public function write($session_id, $data) : bool
+	{
+		$bRes = parent::write($session_id, $data);
+
+		IssueLog::Debug("Write PHP session", \LogChannels::SESSIONTRACKER, [
+			'session_id' => $session_id,
+			'data' => $data,
+		]);
+
+		if ($bRes) {
+			$this->touch_session_file($session_id);
+		}
+
+		return $bRes;
+	}
+
+	public static function session_set_save_handler() : void
+	{
+		if (false === utils::GetConfig()->Get('sessions_tracking.enabled')){
+			//feature disabled
+			return;
+		}
+
+		$sessionhandler = new SessionHandler();
+		session_set_save_handler($sessionhandler, true);
+
+		$iThreshold = utils::GetConfig()->Get('sessions_tracking.gc_threshold');
+		$iThreshold = min(100, $iThreshold);
+		$iThreshold = max(1, $iThreshold);
+		if ((100 != $iThreshold) && (rand(1, 100) > $iThreshold)) {
+			return;
+		}
+
+		$iMaxLifetime = ini_get('session.gc_maxlifetime') ?? 60;
+		$iMaxDurationInSeconds = utils::GetConfig()->Get('sessions_tracking.gc_duration_in_seconds');
+		$sessionhandler->gc_with_time_limit($iMaxLifetime, time() + $iMaxDurationInSeconds);
+	}
+
+	private function generate_session_content(?string $sPreviousFileVersionContent) : ?string
+	{
+		try {
+			$sUserId = UserRights::GetUserId();
+			if (null === $sUserId) {
+				return null;
+			}
+
+			// Default value in case of
+			// - First time file creation
+			// - Data corruption (not a json / not an array / no previous creation_time key)
+			$iCreationTime = time();
+
+			if (! is_null($sPreviousFileVersionContent)) {
+				$aJson = json_decode($sPreviousFileVersionContent, true);
+				if (is_array($aJson) && array_key_exists('creation_time', $aJson)) {
+					$iCreationTime = $aJson['creation_time'];
+				}
+			}
+
+			return json_encode (
+				[
+					'login_mode' => Session::Get('login_mode'),
+					'user_id' => $sUserId,
+					'creation_time' => $iCreationTime,
+					'context' => implode('|', ContextTag::GetStack())
+				]
+			);
+		} catch(Exception $e) {
+
+		}
+
+		return null;
+	}
+
+	private function get_file_path($session_id) : string
+	{
+		return utils::GetDataPath() . "sessions/session_$session_id";
+	}
+
+	private function touch_session_file($session_id) : ?string
+	{
+		if (strlen($session_id) == 0) {
+			return null;
+		}
+
+		clearstatcache();
+		if (! is_dir(utils::GetDataPath() . "sessions")) {
+			@mkdir(utils::GetDataPath() . "sessions");
+		}
+
+		$sFilePath = $this->get_file_path($session_id);
+
+		$sPreviousFileVersionContent = null;
+		if (is_file($sFilePath)) {
+			$sPreviousFileVersionContent = file_get_contents($sFilePath);
+		}
+		$sNewContent = $this->generate_session_content($sPreviousFileVersionContent);
+		if (is_null($sNewContent) || ($sPreviousFileVersionContent === $sNewContent)) {
+			@touch($sFilePath);
+		} else {
+			file_put_contents($sFilePath, $sNewContent);
+		}
+
+		return $sFilePath;
+	}
+
+	private function unlink_session_file($session_id)
+	{
+		$sFilePath = $this->get_file_path($session_id);
+		if (is_file($sFilePath)) {
+			@unlink($sFilePath);
+		}
+	}
+
+	/**
+	 * @param int $max_lifetime
+	 * @param int $iTimeLimit Unix timestamp of time limit not to exceed. -1 for no limit.
+	 *
+	 * @return int
+	 */
+	public function gc_with_time_limit(int $max_lifetime, int $iTimeLimit = -1) : int
+	{
+		$aFiles = $this->list_session_files();
+		$iProcessed = 0;
+		$now = time();
+
+		foreach ($aFiles as $sFile) {
+			if ($now - filemtime($sFile) > $max_lifetime) {
+				@unlink($sFile);
+				$iProcessed++;
+			}
+
+			if (-1 !== $iTimeLimit && time() > $iTimeLimit) {
+				//cleanup processing has to stop after $iTimeLimit
+				break;
+			}
+		}
+
+		return $iProcessed;
+	}
+
+	public function list_session_files() : array
+	{
+		clearstatcache();
+		if (! is_dir(utils::GetDataPath() . "sessions")) {
+			@mkdir(utils::GetDataPath() . "sessions");
+		}
+
+		return glob(utils::GetDataPath() . "sessions/session_*");
+	}
+}

tests/php-unit-tests/unitary-tests/sources/SessionTracker/SessionHandlerTest.php

@@ -0,0 +1,241 @@
+<?php
+
+namespace Combodo\iTop\Test\UnitTest\SessionTracker;
+
+use Combodo\iTop\Application\Helper\Session;
+use Combodo\iTop\SessionTracker\SessionHandler;
+use Combodo\iTop\Test\UnitTest\ItopDataTestCase;
+use ContextTag;
+
+class SessionHandlerTest extends ItopDataTestCase
+{
+	private $aFiles ;
+	private $oTag ;
+
+	protected function setUp(): void
+	{
+		parent::setUp();
+		$this->aFiles=[];
+		$this->oTag = new ContextTag(ContextTag::TAG_REST);
+	}
+
+	protected function tearDown(): void
+	{
+		parent::tearDown();
+		$this->oTag = null;
+
+		foreach ($this->aFiles as $sFile){
+			if (is_file($sFile)){
+				@unlink($sFile);
+			}
+		}
+	}
+
+	private function CreateUserAndLogIn() : ? string {
+		$_SESSION = [];
+		$oUser = $this->CreateContactlessUser("admin" . uniqid(), 1, "1234@Abcdefg");
+
+		\UserRights::Login($oUser->Get('login'));
+		return $oUser->GetKey();
+	}
+
+	private function GenerateSessionContent(SessionHandler $oSessionHandler, ?string $sPreviousFileVersionContent) : ?string {
+		return $this->InvokeNonPublicMethod(SessionHandler::class, "generate_session_content", $oSessionHandler, $aArgs = [$sPreviousFileVersionContent]);
+	}
+
+	/*
+	 * @covers SessionHandler::generate_session_content
+	 */
+	public function testGenerateSessionContentNoUserLoggedIn(){
+		$oSessionHandler = new SessionHandler();
+		$sContent = $this->GenerateSessionContent($oSessionHandler, null);
+		$this->assertNull($sContent, "Session content should be null when there is no user logged in");
+	}
+
+	public function GenerateSessionContentCorruptedPreviousFileContentProvider() {
+		return [
+			'not a json' => [ "not a json" ],
+			'not an array' => [ json_encode("not an array") ],
+			'array without creation_time key' => [ json_encode([]) ],
+		];
+	}
+
+	/**
+	 * @covers SessionHandler::generate_session_content
+	 * @dataProvider GenerateSessionContentCorruptedPreviousFileContentProvider
+	 */
+	public function testGenerateSessionContent_SessionFileRepairment(?string $sFileContent){
+		$sUserId = $this->CreateUserAndLogIn();
+
+		$oSessionHandler = new SessionHandler();
+		Session::Set('login_mode', 'foo_login_mode');
+
+		$sContent = $this->GenerateSessionContent($oSessionHandler, $sFileContent);
+
+		$this->assertNotNull($sContent, 'Should not return null');
+		$aJson = json_decode($sContent, true);
+		$this->assertNotEquals(false, $aJson, 'Should return a valid json string, found: '.$sContent);
+		$this->assertEquals($sUserId, $aJson['user_id'] ?? '', "Should report the login of the logged in user in [user_id]: $sContent");
+		$this->assertEquals(ContextTag::TAG_REST, $aJson['context'] ?? '', "Should report the context tag(s) in [context]: $sContent");
+		$this->assertIsInt($aJson['creation_time'] ?? '', "Should report the session start timestamp in [creation_time]: $sContent");
+		$this->assertEquals('foo_login_mode', $aJson['login_mode'] ?? '', "Should report the current login mode in [login_mode]: $sContent");
+	}
+
+	/*
+	 * @covers SessionHandler::generate_session_content
+	 */
+	public function testGenerateSessionContent(){
+		$sUserId = $this->CreateUserAndLogIn();
+
+		$oSessionHandler = new SessionHandler();
+		Session::Set('login_mode', 'foo_login_mode');
+
+		//first time
+		$sFirstContent = $this->GenerateSessionContent($oSessionHandler, null);
+
+		$this->assertNotNull($sFirstContent, 'Should not return null');
+		$aJson = json_decode($sFirstContent, true);
+		$this->assertNotEquals(false, $aJson, 'Should return a valid json string, found: '.$sFirstContent);
+		$this->assertEquals($sUserId, $aJson['user_id'] ?? '', "Should report the login of the logged in user in [user_id]: $sFirstContent");
+		$this->assertEquals(ContextTag::TAG_REST, $aJson['context'] ?? '', "Should report the context tag(s) in [context]: $sFirstContent");
+		$this->assertIsInt($aJson['creation_time'] ?? '', "Should report the session start timestamp in [creation_time]: $sFirstContent");
+		$this->assertEquals('foo_login_mode', $aJson['login_mode'] ?? '', "Should report the current login mode in [login_mode]: $sFirstContent");
+
+		$iFirstSessionCreationTime = $aJson['creation_time'];
+
+		// Switch context + change user id via impersonation
+		// check it is still tracked in session files
+		$oOtherUser = $this->CreateContactlessUser("admin" . uniqid(), 1, "1234@Abcdefg");
+		$this->assertTrue(\UserRights::Impersonate($oOtherUser->Get('login')), "Failed to execute impersonate on: ".$oOtherUser->Get('login'));
+		$oTag2 = new ContextTag(ContextTag::TAG_SYNCHRO);
+		$sNewContent = $this->GenerateSessionContent($oSessionHandler, $sFirstContent);
+		$this->assertNotNull($sNewContent, 'Should not return null');
+		$aJson = json_decode($sNewContent, true);
+		$this->assertNotEquals(false, $aJson, 'Should return a valid json string, found: '.$sNewContent);
+		$this->assertEquals(ContextTag::TAG_REST . '|' . ContextTag::TAG_SYNCHRO, $aJson['context'] ?? '', "After impersonation, should report the new context tags in [context]: $sNewContent");
+		$this->assertEquals($iFirstSessionCreationTime, $aJson['creation_time'] ?? '', "After impersonation, should still report the the session start timestamp in [creation_time]: $sNewContent");
+		$this->assertEquals('foo_login_mode', $aJson['login_mode'] ?? '', "After impersonation, should still report the login mode in [login_mode]: $sNewContent");
+		$this->assertEquals($oOtherUser->GetKey(), $aJson['user_id'] ?? '', "Should report the impersonate user in [user_id]: $sNewContent");
+	}
+
+	private function touchSessionFile(SessionHandler $oSessionHandler, $session_id) : ?string {
+		$sRes = $this->InvokeNonPublicMethod(SessionHandler::class, "touch_session_file", $oSessionHandler, $aArgs = [$session_id]);
+		if (!is_null($sRes) && is_file($sRes)) {
+			// Record the file for cleanup on tearDown
+			$this->aFiles[] = $sRes;
+		}
+		clearstatcache();
+		return $sRes;
+	}
+
+	/*
+	 * @covers SessionHandler::touch_session_file
+	 */
+	public function testTouchSessionFile_NoUserLoggedIn(){
+		$oSessionHandler = new SessionHandler();
+		$session_id = uniqid();
+		$sFile = $this->touchSessionFile($oSessionHandler, $session_id);
+		$this->assertEquals(true, is_file($sFile), "Should return a file name: '$sFile' is not a valid file name");
+		$sContent = file_get_contents($sFile);
+		$this->assertEquals(null, $sContent, 'Should create an empty file, found: '.$sContent);
+	}
+
+	/*
+	 * @covers SessionHandler::touch_session_file
+	 */
+	public function testTouchSessionFile_UserLoggedIn(){
+		$sUserId = $this->CreateUserAndLogIn();
+		Session::Set('login_mode', 'foo_login_mode');
+
+		$oSessionHandler = new SessionHandler();
+		$session_id = uniqid();
+		$sFile = $this->touchSessionFile($oSessionHandler, $session_id);
+		$this->assertEquals(true, is_file($sFile), "Should return a file name: '$sFile' is not a valid file name");
+		$sFirstContent = file_get_contents($sFile);
+
+		$iFirstCTime = filectime($sFile) - 1;
+		// Set it in the past to check that it will be further updated (without the need to sleep...)
+		touch($sFile, $iFirstCTime);
+
+		$this->assertNotNull($sFirstContent, 'Should not return null');
+		$aJson = json_decode($sFirstContent, true);
+		$this->assertNotEquals(false, $aJson, 'Should return a valid json string, found: '.$sFirstContent);
+		$this->assertEquals($sUserId, $aJson['user_id'] ?? '', "Should report the login of the logged in user in [user_id]: $sFirstContent");
+		$this->assertEquals(ContextTag::TAG_REST, $aJson['context'] ?? '', "Should report the context tag(s) in [context]: $sFirstContent");
+		$this->assertIsInt($aJson['creation_time'] ?? '', "Should report the session start timestamp in [creation_time]: $sFirstContent");
+		$this->assertEquals('foo_login_mode', $aJson['login_mode'] ?? '', "Should report the current login mode in [login_mode]: $sFirstContent");
+
+		$this->touchSessionFile($oSessionHandler, $session_id);
+		$sNewContent = file_get_contents($sFile);
+		$this->assertEquals($sFirstContent, $sNewContent, 'On successive calls, should not modify an existing session file');
+		$this->assertGreaterThan($iFirstCTime, filectime($sFile), 'On successive calls, should have changed the file ctime');
+	}
+
+	/**
+	 * @covers SessionHandler::touch_session_file
+	 */
+	public function testTouchSessionFileWithEmptySessionId() {
+		$this->CreateUserAndLogIn();
+		Session::Set('login_mode', 'toto');
+
+		$oSessionHandler = new SessionHandler();
+		$this->assertNull($this->touchSessionFile($oSessionHandler, ''), 'Should return null when session id is an empty string');
+		$this->assertNull($this->touchSessionFile($oSessionHandler, false), 'Should return null when session id (boolean) false');
+	}
+
+	private function GetFilePath(SessionHandler $oSessionHandler, $session_id) : string {
+		$sFile = $this->InvokeNonPublicMethod(SessionHandler::class, "get_file_path", $oSessionHandler, $aArgs = [$session_id]);
+		// Record file for cleanup on tearDown
+		$this->aFiles[] = $sFile;
+		return $sFile;
+	}
+
+	public function GgcWithTimeLimitProvider(){
+		return [
+			'no cleanup time limit' => [
+				'iTimeLimit' => -1,
+				'iExpectedProcessed' => 2
+			],
+			'cleanup time limit in the pass => first file removed only' => [
+				'iTimeLimit' => time() - 1,
+				'iExpectedProcessed' => 1
+			],
+		];
+	}
+
+	/**
+	 * @covers SessionHandler::gc_with_time_limit
+	 * @covers SessionHandler::list_session_files
+	 * @dataProvider GgcWithTimeLimitProvider
+	 */
+	public function testGgcWithTimeLimit($iTimeLimit, $iExpectedProcessed) {
+		$oSessionHandler = new SessionHandler();
+		//remove all first
+		$oSessionHandler->gc_with_time_limit(-1);
+		$this->assertEquals([], $oSessionHandler->list_session_files(), 'list_session_files should report no file at startup');
+
+		$max_lifetime = 1440;
+		$iNbExpiredFiles = 2;
+		$iNbFiles = 5;
+		$iExpiredTimeStamp = time() - $max_lifetime - 1;
+		for($i=0; $i<$iNbFiles; $i++) {
+			$sFile = $this->GetFilePath($oSessionHandler, uniqid());
+			file_put_contents($sFile, "fakedata");
+
+			if ($iNbExpiredFiles > 0){
+				$iNbExpiredFiles--;
+				touch($sFile, $iExpiredTimeStamp);
+			}
+		}
+
+		$aFoundSessionFiles = $oSessionHandler->list_session_files();
+		$this->assertEquals($iNbFiles, sizeof($aFoundSessionFiles), 'list_session_files should reports all files');
+		foreach ($aFoundSessionFiles as $sFile){
+			$this->assertTrue(is_file($sFile), 'list_session_files should return a valid file paths, found: '.$sFile);
+		}
+
+		$iProcessed = $oSessionHandler->gc_with_time_limit($max_lifetime, $iTimeLimit);
+		$this->assertEquals($iExpectedProcessed, $iProcessed, 'gc_with_time_limit should report the count of expired files');
+		$this->assertEquals($iNbFiles - $iExpectedProcessed, sizeof($oSessionHandler->list_session_files()), 'gc_with_time_limit should actually remove all processed files');
+	}
+}

webservices/cron.php

@@ -108,7 +108,7 @@ function RunTask(BackgroundTask $oTask, $iTimeLimit)
 		// Time in seconds allowed to the task
 		$iCurrTimeLimit = $iTimeLimit;
 		// Compute allowed time
-		if ($oRefClass->implementsInterface('iScheduledProcess') === false) 
+		if ($oRefClass->implementsInterface('iScheduledProcess') === false)
 		{
 			// Periodic task, allow only X times ($iMaxTaskExecutionTime) its periodicity (GetPeriodicity())
 			$iMaxTaskExecutionTime = MetaModel::GetConfig()->Get('cron_task_max_execution_time');
@@ -148,7 +148,7 @@ function RunTask(BackgroundTask $oTask, $iTimeLimit)
 		$oTask->Set('first_run_date', $oDateStarted->format('Y-m-d H:i:s'));
 	}
 	$oTask->ComputeDurations($fDuration); // does increment the counter and compute statistics
-	
+
 	// Update the timestamp since we want to be able to re-order the tasks based on the time they finished
 	$oDateEnded = new DateTime();
 	$oTask->Set('latest_run_date', $oDateEnded->format('Y-m-d H:i:s'));