Fixes yiisoft#3872: Added database-based StatePersister implementation

CHANGELOG

@@ -28,6 +28,7 @@ Version 1.1.17 work in progress
 - Enh #3686: Wrapper div of hidden fields in CForm now have style `display:none` instead of `visibility:hidden` to not affect the layout (cebe, alaabadran)
 - Enh #3738: It is now possible to override the value of 'required' html option in `CHtml::activeLabelEx()` (matteosistisette)
 - Enh #3827: Added the $options parameter to be used in stream_socket_client in CRedisCache.
+- Enh #3872: Added database-based StatePersister implementation (AloneCoder)
 - Enh #3948: Enhanced CHttpRequest path info extraction for compatibility with PHP 7 (dmitrivereshchagin)
 - Enh #3949: Added `$overwriteAll` argument to `CConsoleCommand::copyFiles()` which can be set to true in noninteractive commands (dmitrivereshchagin)
 - Chg #3776: Autoloader now doesn't error in case of non-existing namespaced classes so other autoloaders have chance to handle these (alexandernst)

framework/YiiBase.php

@@ -652,6 +652,7 @@ public static function registerAutoloader($callback, $append=false)
 		'CApplicationComponent' => '/base/CApplicationComponent.php',
 		'CBehavior' => '/base/CBehavior.php',
 		'CComponent' => '/base/CComponent.php',
+		'CDbStatePersister' => '/base/CDbStatePersister.php',
 		'CErrorEvent' => '/base/CErrorEvent.php',
 		'CErrorHandler' => '/base/CErrorHandler.php',
 		'CException' => '/base/CException.php',

framework/base/CDbStatePersister.php

@@ -0,0 +1,153 @@
+<?php
+/**
+ * CDbStatePersister class file.
+ *
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @link http://www.yiiframework.com/
+ * @copyright 2008-2013 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ * @package system.base
+ * @since 1.1.17
+ */
+
+/**
+ * CDbStatePersister implements a database persistent data storage.
+ *
+ * It can be used to keep data available through multiple requests and sessions.
+ *
+ * By default, CDbStatePersister stores data in a table named 'state'.
+ * You may change the location by setting the {@link stateTableName} property.
+ *
+ * To retrieve the data from CDbStatePersister, call {@link load()}. To save the data,
+ * call {@link save()}.
+ *
+ * Comparison among state persister, session and cache is as follows:
+ * <ul>
+ * <li>session: data persisting within a single user session.</li>
+ * <li>state persister: data persisting through all requests/sessions (e.g. hit counter).</li>
+ * <li>cache: volatile and fast storage. It may be used as storage medium for session or state persister.</li>
+ * </ul>
+ *
+ * @package system.base
+ * @since 1.1.17
+ */
+class CDbStatePersister extends CApplicationComponent implements IStatePersister
+{
+	/**
+	 * @var string the database table name storing the state data. Make sure the table
+	 * exists or database user is granted to CREATE tables.
+	 */
+	public $stateTableName='state';
+	/**
+	 * @var string connection ID
+	 */
+	public $dbComponent='db';
+	/**
+	 * @var CDbConnection instance
+	 */
+	public $db;
+
+	/**
+	 * @var string Column name for value-field
+	 */
+	public $valueField='value';
+	/**
+	 * @var string Column name for key-field
+	 */
+	public $keyField='key';
+
+	/**
+	 * Initializes the component.
+	 * This method overrides the parent implementation by making sure {@link stateFile}
+	 * contains valid value.
+	 */
+	public function init()
+	{
+		parent::init();
+		if($this->stateTableName===null)
+			throw new CException(Yii::t('yii', 'stateTableName param cannot be null.'));
+		$this->db=Yii::app()->getComponent($this->dbComponent);
+		if($this->db===null)
+			throw new CException(Yii::t('yii', '\'{db}\' component doesn\'t exist.',array(
+				'{db}'=>$this->dbComponent
+			)));
+		if(!($this->db instanceof CDbConnection))
+            throw new CException(Yii::t ('yii', '\'{db}\' component is not a valid CDbConnection instance.',array(
+				'{db}'=>$this->dbComponent
+			)));
+		if($this->db->schema->getTable($this->stateTableName,true)===null)
+			$this->createTable();
+	}
+
+	/**
+	 * Loads state data from persistent storage.
+	 * @return mixed state data. Null if no state data available.
+	 */
+	public function load()
+	{
+		$command=$this->db->createCommand();
+		$command=$command->select($this->valueField)->from($this->stateTableName);
+		$command=$command->where($this->db->quoteColumnName($this->keyField).'=:key',array(
+			':key'=>Yii::app()->name
+		));
+		$state=$command->queryScalar();
+		if(false!==$state)
+			return unserialize($state);
+		else
+			return null;
+	}
+
+	/**
+	 * Saves application state in persistent storage.
+	 * @param mixed $state state data (must be serializable).
+	 * @return int
+	 */
+	public function save($state)
+	{
+		$command=$this->db->createCommand();
+		if(false===$this->exists())
+			return $command->insert($this->stateTableName,array(
+				$this->keyField=>Yii::app()->name,
+				$this->valueField=>serialize($state)
+			));
+		else
+            return $command->update($this->stateTableName,array($this->valueField=>serialize($state)),
+				$this->db->quoteColumnName($this->keyField).'=:key',
+				array(':key'=>Yii::app()->name)
+		);
+	}
+
+	/**
+	 * @return mixed
+	 */
+	public function exists()
+	{
+		$command=$this->db->createCommand();
+		$command=$command->select($this->keyField)->from($this->stateTableName);
+		$command=$command->where($this->db->quoteColumnName($this->keyField).'=:key',array(
+			':key'=>Yii::app()->name
+		));
+		return $command->queryScalar();
+	}
+
+	/**
+	 * Creates state persister table
+	 * @throws CException
+	 */
+	protected function createTable()
+	{
+		try
+		{
+			$command=$this->db->createCommand();
+			$command->createTable($this->stateTableName,array(
+				$this->keyField=>'string NOT NULL',
+				$this->valueField=>'text NOT NULL',
+				'PRIMARY KEY ('.$this->db->quoteColumnName($this->keyField).')'
+			));
+		}
+		catch (CDbException $e)
+		{
+			throw new CException(Yii::t('yii','Can\'t create state persister table. Check CREATE privilege for \'{db}\' connection user or create table manually with SQL: {sql}.',array('{db}'=>$this->dbComponent,'{sql}'=>$command->text ) ) );
+		}
+	}
+}

framework/yiilite.php

@@ -361,6 +361,7 @@ public static function registerAutoloader($callback, $append=false)
 		'CApplicationComponent' => '/base/CApplicationComponent.php',
 		'CBehavior' => '/base/CBehavior.php',
 		'CComponent' => '/base/CComponent.php',
+        'CDbStatePersister' => '/base/CDbStatePersister.php',
 		'CErrorEvent' => '/base/CErrorEvent.php',
 		'CErrorHandler' => '/base/CErrorHandler.php',
 		'CException' => '/base/CException.php',

tests/framework/base/CDbStatePersisterTest.php

@@ -0,0 +1,37 @@
+<?php
+
+class CDbStatePersisterTest extends CTestCase
+{
+	public function setUp()
+	{
+		if(!extension_loaded('pdo') || !extension_loaded('pdo_sqlite'))
+			$this->markTestSkipped('PDO and SQLite extensions are required.');
+		// clean up runtime directory
+		$app=new TestApplication;
+		$app->reset();
+	}
+
+	public function testLoadSave()
+	{
+		$app=new TestApplication(array(
+			'components'=>array(
+				'db'=>array(
+					'class' => 'CDbConnection',
+					'connectionString' => 'mysql:host=127.0.0.1;port=3306;dbname=yii',
+					'username' => 'test',
+					'password' => 'test',
+					'emulatePrepare' => true,
+					'charset' => 'utf8',
+					'enableParamLogging' => true,
+				),
+				'statePersister' => array(
+					'class' => 'CDbStatePersister'
+				)
+			)
+		));
+		$sp=$app->statePersister;
+		$data=array('123','456','a'=>443);
+		$sp->save($data);
+		$this->assertEquals($sp->load(),$data);
+	}
+}