added redis Session

as suggested in issue #1316

extensions/redis/Cache.php

@@ -40,7 +40,7 @@ use yii\base\InvalidConfigException;
  * ]
  * ~~~
  *
- * Or if you have configured the redis connection as an application component, the following is sufficient:
+ * Or if you have configured the redis [[Connection]] as an application component, the following is sufficient:
  *
  * ~~~
  * [

extensions/redis/README.md

@@ -1,9 +1,9 @@
-Redis Cache and ActiveRecord for Yii 2
+Redis Cache, Session and ActiveRecord for Yii 2
-======================================
+===============================================
 
 This extension provides the [redis](http://redis.io/) key-value store support for the Yii2 framework.
-It includes a `Cache` class and implents the `ActiveRecord` pattern that allows you to store active
+It includes a `Cache` and `Session` storage handler and implents the `ActiveRecord` pattern that allows
-records in redis.
+you to store active records in redis.
 
 To use this extension, you have to configure the Connection class in your application configuration:
 
@@ -21,7 +21,31 @@ return [
 ];
 ```
 
-To use the `Cache` component, you also have to configure the `cache` component to be `yii\redis\Cache`:
+Installation
+------------
+
+The preferred way to install this extension is through [composer](http://getcomposer.org/download/).
+
+Either run
+
+```
+php composer.phar require yiisoft/yii2-redis "*"
+```
+
+or add
+
+```json
+"yiisoft/yii2-redis": "*"
+```
+
+to the require section of your composer.json.
+
+
+Using the Cache component
+-------------------------
+
+To use the `Cache` component, in addtition to configuring the connection as described above,
+you also have to configure the `cache` component to be `yii\redis\Cache`:
 
 ```php
 return [
@@ -36,7 +60,7 @@ return [
 ```
 
 If you only use the redis cache, you can also configure the parameters of the connection within the
-cache component:
+cache component (no connection application component needs to be configured in this case):
 
 ```php
 return [
@@ -55,26 +79,44 @@ return [
 ];
 ```
 
+Using the Session component
+---------------------------
 
-Installation
+To use the `Session` component, in addtition to configuring the connection as described above,
-------------
+you also have to configure the `session` component to be `yii\redis\Session`:
-
-The preferred way to install this extension is through [composer](http://getcomposer.org/download/).
 
-Either run
+```php
-
+return [
-```
+	//....
-php composer.phar require yiisoft/yii2-redis "*"
+	'components' => [
+	    // ...
+        'session' => [
+            'class' => 'yii\redis\Session',
+        ],
+	]
+];
 ```
 
-or add
+If you only use the redis session, you can also configure the parameters of the connection within the
+cache component (no connection application component needs to be configured in this case):
 
-```json
+```php
-"yiisoft/yii2-redis": "*"
+return [
+	//....
+	'components' => [
+	    // ...
+        'session' => [
+            'class' => 'yii\redis\Session',
+            'redis' => [
+                'hostname' => 'localhost',
+                'port' => 6379,
+                'database' => 0,
+            ],
+        ],
+	]
+];
 ```
 
-to the require section of your composer.json.
-
 
 Using the redis ActiveRecord
 ----------------------------
@@ -92,10 +134,29 @@ The following is an example model called `Customer`:
 ```php
 class Customer extends \yii\redis\ActiveRecord
 {
-    public function attributes()
+     /**
-    {
+      * @return array the list of attributes for this record
-        return ['id', 'name', 'address', 'registration_date'];
+      */
-    }
+     public function attributes()
+     {
+         return ['id', 'name', 'address', 'registration_date'];
+     }
+
+     /**
+      * @return ActiveRelation defines a relation to the Order record (can be in other database, e.g. elasticsearch or sql)
+      */
+     public function getOrders()
+     {
+         return $this->hasMany(Order::className(), ['customer_id' => 'id']);
+     }
+
+     /**
+      * Defines a scope that modifies the `$query` to return only active(status = 1) customers
+      */
+     public static function active($query)
+     {
+         $query->andWhere(array('status' => 1));
+     }
 }
 ```
 
@@ -108,4 +169,16 @@ It supports the same interface and features except the following limitations:
   (orderBy() is not yet implemented: [#1305](https://github.com/yiisoft/yii2/issues/1305))
 - `via`-relations can not be defined via a table as there are not tables in redis. You can only define relations via other records.
 
-It is also possible to define relations from redis ActiveRecords to normal ActiveRecord classes and vice versa.
+It is also possible to define relations from redis ActiveRecords to normal ActiveRecord classes and vice versa.
+
+Usage example:
+
+```php
+$customer = new Customer();
+$customer->attributes = ['name' => 'test'];
+$customer->save();
+echo $customer->id; // id will automatically be incremented if not set explicitly
+
+$customer = Customer::find()->where(['name' => 'test'])->one(); // find by query
+$customer = Customer::find()->active()->all(); // find all by query (using the `active` scope)
+```

extensions/redis/Session.php

@@ -0,0 +1,157 @@
+<?php
+/**
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright (c) 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\redis;
+
+use Yii;
+use yii\base\InvalidConfigException;
+
+/**
+ * Redis Session implements a session component using [redis](http://redis.io/) as the storage medium.
+ *
+ * Redis Session requires redis version 2.6.12 or higher to work properly.
+ *
+ * It needs to be configured with a redis [[Connection]] that is also configured as an application component.
+ * By default it will use the `redis` application component.
+ *
+ * To use redis Session as the session application component, configure the application as follows,
+ *
+ * ~~~
+ * [
+ *     'components' => [
+ *         'session' => [
+ *             'class' => 'yii\redis\Session',
+ *             'redis' => [
+ *                 'hostname' => 'localhost',
+ *                 'port' => 6379,
+ *                 'database' => 0,
+ *             ]
+ *         ],
+ *     ],
+ * ]
+ * ~~~
+ *
+ * Or if you have configured the redis [[Connection]] as an application component, the following is sufficient:
+ *
+ * ~~~
+ * [
+ *     'components' => [
+ *         'session' => [
+ *             'class' => 'yii\redis\Session',
+ *             // 'redis' => 'redis' // id of the connection application component
+ *         ],
+ *     ],
+ * ]
+ * ~~~
+ *
+ * @property boolean $useCustomStorage Whether to use custom storage. This property is read-only.
+ *
+ * @author Carsten Brandt <mail@cebe.cc>
+ * @since 2.0
+ */
+class Session extends \yii\web\Session
+{
+	/**
+	 * @var Connection|string|array the Redis [[Connection]] object or the application component ID of the Redis [[Connection]].
+	 * This can also be an array that is used to create a redis [[Connection]] instance in case you do not want do configure
+	 * redis connection as an application component.
+	 * After the Session object is created, if you want to change this property, you should only assign it
+	 * with a Redis [[Connection]] object.
+	 */
+	public $redis = 'redis';
+	/**
+	 * @var string a string prefixed to every cache key so that it is unique. If not set,
+	 * it will use a prefix generated from [[Application::id]]. You may set this property to be an empty string
+	 * if you don't want to use key prefix. It is recommended that you explicitly set this property to some
+	 * static value if the cached data needs to be shared among multiple applications.
+	 *
+	 * To ensure interoperability, only alphanumeric characters should be used.
+	 */
+	public $keyPrefix;
+
+
+	/**
+	 * Initializes the redis Session component.
+	 * This method will initialize the [[redis]] property to make sure it refers to a valid redis connection.
+	 * @throws InvalidConfigException if [[redis]] is invalid.
+	 */
+	public function init()
+	{
+		parent::init();
+		if (is_string($this->redis)) {
+			$this->redis = Yii::$app->getComponent($this->redis);
+		} else if (is_array($this->redis)) {
+			if (!isset($this->redis['class'])) {
+				$this->redis['class'] = Connection::className();
+			}
+			$this->redis = Yii::createObject($this->redis);
+		}
+		if (!$this->redis instanceof Connection) {
+			throw new InvalidConfigException("Session::redis must be either a Redis connection instance or the application component ID of a Redis connection.");
+		}
+		if ($this->keyPrefix === null) {
+			$this->keyPrefix = substr(md5(Yii::$app->id), 0, 5);
+		} elseif (!ctype_alnum($this->keyPrefix)) {
+			throw new InvalidConfigException(get_class($this) . '::keyPrefix should only contain alphanumeric characters.');
+		}
+	}
+
+	/**
+	 * Returns a value indicating whether to use custom session storage.
+	 * This method overrides the parent implementation and always returns true.
+	 * @return boolean whether to use custom storage.
+	 */
+	public function getUseCustomStorage()
+	{
+		return true;
+	}
+
+	/**
+	 * Session read handler.
+	 * Do not call this method directly.
+	 * @param string $id session ID
+	 * @return string the session data
+	 */
+	public function readSession($id)
+	{
+		$data = $this->redis->executeCommand('GET', [$this->calculateKey($id)]);
+		return $data === false ? '' : $data;
+	}
+
+	/**
+	 * Session write handler.
+	 * Do not call this method directly.
+	 * @param string $id session ID
+	 * @param string $data session data
+	 * @return boolean whether session write is successful
+	 */
+	public function writeSession($id, $data)
+	{
+		return (bool) $this->redis->executeCommand('SET', [$this->calculateKey($id), $data, 'EX', $this->getTimeout()]);
+	}
+
+	/**
+	 * Session destroy handler.
+	 * Do not call this method directly.
+	 * @param string $id session ID
+	 * @return boolean whether session is destroyed successfully
+	 */
+	public function destroySession($id)
+	{
+		return (bool) $this->redis->executeCommand('DEL', [$this->calculateKey($id)]);
+	}
+
+	/**
+	 * Generates a unique key used for storing session data in cache.
+	 * @param string $id session variable name
+	 * @return string a safe cache key associated with the session variable name
+	 */
+	protected function calculateKey($id)
+	{
+		return $this->keyPrefix . md5(json_encode([__CLASS__, $id]));
+	}
+}

extensions/redis/composer.json

@@ -1,7 +1,7 @@
 {
 	"name": "yiisoft/yii2-redis",
-	"description": "Redis Cache and ActiveRecord for the Yii framework",
+	"description": "Redis Cache, Session and ActiveRecord for the Yii framework",
-	"keywords": ["yii", "redis", "active-record", "cache"],
+	"keywords": ["yii", "redis", "active-record", "cache", "session"],
 	"type": "yii2-extension",
 	"license": "BSD-3-Clause",
 	"support": {

framework/yii/caching/Cache.php

@@ -58,7 +58,7 @@ abstract class Cache extends Component implements \ArrayAccess
 	 * if you don't want to use key prefix. It is recommended that you explicitly set this property to some
 	 * static value if the cached data needs to be shared among multiple applications.
 	 *
-	 * To ensure interoperability, only use alphanumeric characters should be used.
+	 * To ensure interoperability, only alphanumeric characters should be used.
 	 */
 	public $keyPrefix;
 	/**