summaryrefslogtreecommitdiff
path: root/lib/prado/framework/Web/TCacheHttpSession.php
blob: 604eef4465a69b10d0b6734439d6a17a83c8e38c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
<?php
/**
 * TCacheHttpSession class
 *
 * @author Carl G. Mathisen <carlgmathisen@gmail.com>
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @link https://github.com/pradosoft/prado
 * @copyright Copyright &copy; 2005-2015 The PRADO Group
 * @license https://github.com/pradosoft/prado/blob/master/COPYRIGHT
 * @package System.Web
 * @since 3.1.1
 */

/**
 * TCacheHttpSession class
 *
 * TCacheHttpSession provides access for storing session data using a cache module (e.g. TMemCache, TDbCache).
 * To specify the cache module for data storage, set the {@link setCacheModuleID CacheModuleID} property
 * which should refer to a valid cache module configured in the application configuration.
 *
 * The following example shows how we configure TCacheHttpSession:
 * <code>
 *  <modules>
 *    <module id="cache" class="System.Caching.TMemCache" Host="localhost" Port="11211" />
 *    <module id="session" class="System.Web.TCacheHttpSession"
 *         CacheModuleID="cache" SessionName="SSID"
 *         CookieMode="Allow" AutoStart="true" GCProbability="1"
 *         UseTransparentSessionID="true" TimeOut="3600" />
 *  </modules>
 * </code>
 *
 * Beware, by definition cache storage are volatile, which means the data stored on them
 * may be swapped out and get lost. This may not be the case for certain cache storage,
 * such as database. So make sure you manage your cache properly to avoid loss of session data.
 *
 * @author Carl G. Mathisen <carlgmathisen@gmail.com>
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @package System.Web
 * @since 3.1.1
 */
class TCacheHttpSession extends THttpSession
{
	private $_prefix='session';
	private $_cacheModuleID='';
	private $_cache;

	/**
	 * Initializes the module.
	 * This method is required by IModule.
	 * It reads the CacheModule property.
	 * @param TXmlElement module configuration
	 */
    public function init($config)
    {
		if($this->_cacheModuleID==='')
			throw new TConfigurationException('cachesession_cachemoduleid_required');
		else if(($cache=$this->getApplication()->getModule($this->_cacheModuleID))===null)
			throw new TConfigurationException('cachesession_cachemodule_inexistent',$this->_cacheModuleID);
		else if($cache instanceof ICache)
			$this->_cache=$cache;
		else
			throw new TConfigurationException('cachesession_cachemodule_invalid',$this->_cacheModuleID);
		$this->setUseCustomStorage(true);
		parent::init($config);
    }

	/**
	 * @return string the ID of the cache module.
	 */
	public function getCacheModuleID()
	{
		return $this->_cacheModuleID;
	}

	/**
	 * @param string the ID of the cache module.
	 */
	public function setCacheModuleID($value)
	{
		$this->_cacheModuleID=$value;
	}

	/**
	 * @return ICache the cache module being used for data storage
	 */
	public function getCache()
	{
		return $this->_cache;
	}

	/**
	 * Session read handler.
	 * @param string session ID
	 * @return string the session data
	 */
	public function _read($id)
	{
	    return $this->_cache->get($this->calculateKey($id));
	}

	/**
	 * Session write handler.
	 * @param string session ID
	 * @param string session data
	 * @return boolean whether session write is successful
	 */
	public function _write($id,$data)
	{
		return $this->_cache->set($this->calculateKey($id),$data,$this->getTimeout());
	}

	/**
	 * Session destroy handler.
	 * This method should be overriden if {@link setUseCustomStorage UseCustomStorage} is set true.
	 * @param string session ID
	 * @return boolean whether session is destroyed successfully
	 */
	public function _destroy($id)
	{
	    return $this->_cache->delete($this->calculateKey($id));
	}

	/**
	 * @return string prefix of session variable name to avoid conflict with other cache data. Defaults to 'session'.
	 */
	public function getKeyPrefix()
	{
	    return $this->_prefix;
	}

	/**
     * @param string prefix of session variable name to avoid conflict with other cache data
     */
	public function setKeyPrefix($value)
	{
	    $this->_prefix=$value;
	}

	/**
	 * @param string session variable name
	 * @return string a safe cache key associated with the session variable name
	 */
	protected function calculateKey($id)
	{
	    return $this->_prefix.':'.$id;
	}
}