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<?php |
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namespace SilverStripe\Control; |
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use SilverStripe\Core\Config\Config; |
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use SilverStripe\Core\Injector\Injectable; |
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use SilverStripe\Core\Injector\Injector; |
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use SilverStripe\Dev\Deprecation; |
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/** |
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* Handles all manipulation of the session. |
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* |
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* The static methods are used to manipulate the currently active controller's session. |
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* The instance methods are used to manipulate a particular session. There can be more than one of these created. |
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* |
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* In order to support things like testing, the session is associated with a particular Controller. In normal usage, |
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* this is loaded from and saved to the regular PHP session, but for things like static-page-generation and |
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* unit-testing, you can create multiple Controllers, each with their own session. |
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* |
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* The instance object is basically just a way of manipulating a set of nested maps, and isn't specific to session |
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* data. |
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* |
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* <b>Saving Data</b> |
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* |
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* You can write a value to a users session from your PHP code using the static function {@link Session::set()}. You |
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* can add this line in any function or file you wish to save the value. |
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* |
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* <code> |
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* Session::set('MyValue', 6); |
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* </code> |
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* |
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* Saves the value of "6" to the MyValue session data. You can also save arrays or serialized objects in session (but |
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* note there may be size restrictions as to how much you can save) |
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* |
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* <code> |
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* // save a variable |
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* $var = 1; |
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* Session::set('MyVar', $var); |
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* |
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* // saves an array |
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* Session::set('MyArrayOfValues', array('1', '2', '3')); |
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* |
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* // saves an object (you'll have to unserialize it back) |
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* $object = new Object(); |
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* |
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* Session::set('MyObject', serialize($object)); |
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* </code> |
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* |
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* <b>Accessing Data</b> |
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* |
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* Once you have saved a value to the Session you can access it by using the {@link Session::get()} function. |
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* Like the {@link Session::set()} function you can use this anywhere in your PHP files. |
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* |
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* The values in the comments are the values stored from the previous example. |
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* |
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* <code> |
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* public function bar() { |
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* $value = Session::get('MyValue'); // $value = 6 |
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* $var = Session::get('MyVar'); // $var = 1 |
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* $array = Session::get('MyArrayOfValues'); // $array = array(1,2,3) |
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* $object = Session::get('MyObject', unserialize($object)); // $object = Object() |
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* } |
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* </code> |
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* |
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* You can also get all the values in the session at once. This is useful for debugging. |
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* |
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* <code> |
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* Session::get_all(); // returns an array of all the session values. |
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* </code> |
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* |
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* <b>Clearing Data</b> |
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* |
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* Once you have accessed a value from the Session it doesn't automatically wipe the value from the Session, you have |
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* to specifically remove it. To clear a value you can either delete 1 session value by the name that you saved it |
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* |
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* <code> |
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* Session::clear('MyValue'); // MyValue is no longer 6. |
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* </code> |
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* |
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* Or you can clear every single value in the session at once. Note SilverStripe stores some of its own session data |
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* including form and page comment information. None of this is vital but clear_all will clear everything. |
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* |
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* <code> |
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* Session::clear_all(); |
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* </code> |
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* |
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* @see Cookie |
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* @todo This class is currently really basic and could do with a more well-thought-out implementation. |
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*/ |
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class Session |
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{ |
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use Injectable; |
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/** |
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* Set session timeout in seconds. |
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* |
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* @var int |
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* @config |
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*/ |
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private static $timeout = 0; |
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/** |
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* @config |
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* @var array |
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*/ |
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private static $session_ips = array(); |
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/** |
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* @config |
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* @var string |
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*/ |
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private static $cookie_domain; |
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/** |
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* @config |
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* @var string |
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*/ |
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private static $cookie_path; |
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/** |
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* @config |
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* @var string |
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*/ |
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private static $session_store_path; |
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/** |
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* @config |
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* @var boolean |
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*/ |
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private static $cookie_secure = false; |
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/** |
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* Session data |
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*/ |
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protected $data = array(); |
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protected $changedData = array(); |
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protected function userAgent() |
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{ |
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if (isset($_SERVER['HTTP_USER_AGENT'])) { |
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return $_SERVER['HTTP_USER_AGENT']; |
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} else { |
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return ''; |
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} |
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} |
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/** |
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* Start PHP session, then create a new Session object with the given start data. |
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* |
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* @param $data array|Session Can be an array of data (such as $_SESSION) or another Session object to clone. |
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*/ |
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public function __construct($data) |
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{ |
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if ($data instanceof Session) { |
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$data = $data->inst_getAll(); |
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} |
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$this->data = $data; |
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if (isset($this->data['HTTP_USER_AGENT'])) { |
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if ($this->data['HTTP_USER_AGENT'] != $this->userAgent()) { |
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// Funny business detected! |
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$this->inst_clearAll(); |
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$this->inst_destroy(); |
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$this->inst_start(); |
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} |
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} |
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} |
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/** |
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* Add a value to a specific key in the session array |
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* |
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* @param string $name |
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* @param mixed $val |
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*/ |
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public static function add_to_array($name, $val) |
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{ |
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return self::current_session()->inst_addToArray($name, $val); |
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} |
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/** |
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* Set a key/value pair in the session |
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* |
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* @param string $name Key |
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* @param string $val Value |
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*/ |
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public static function set($name, $val) |
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{ |
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return self::current_session()->inst_set($name, $val); |
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} |
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/** |
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* Return a specific value by session key |
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* |
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* @param string $name Key to lookup |
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* @return mixed |
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*/ |
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public static function get($name) |
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{ |
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return self::current_session()->inst_get($name); |
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} |
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/** |
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* Return all the values in session |
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* |
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* @return array |
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*/ |
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public static function get_all() |
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{ |
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return self::current_session()->inst_getAll(); |
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} |
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/** |
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* Clear a given session key, value pair. |
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* |
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* @param string $name Key to lookup |
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*/ |
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public static function clear($name) |
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{ |
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return self::current_session()->inst_clear($name); |
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} |
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/** |
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* Clear all the values |
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* |
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* @return void |
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*/ |
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public static function clear_all() |
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{ |
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self::current_session()->inst_clearAll(); |
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self::$default_session = null; |
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} |
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/** |
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* Save all the values in our session to $_SESSION |
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*/ |
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public static function save() |
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{ |
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return self::current_session()->inst_save(); |
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} |
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protected static $default_session = null; |
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protected static function current_session() |
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{ |
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if (Controller::has_curr()) { |
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return Controller::curr()->getSession(); |
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} else { |
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if (!self::$default_session) { |
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self::$default_session = Injector::inst()->create('SilverStripe\\Control\\Session', isset($_SESSION) ? $_SESSION : array()); |
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} |
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return self::$default_session; |
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} |
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} |
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public function inst_start($sid = null) |
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{ |
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$path = Config::inst()->get('SilverStripe\\Control\\Session', 'cookie_path'); |
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if (!$path) { |
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$path = Director::baseURL(); |
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} |
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$domain = Config::inst()->get('SilverStripe\\Control\\Session', 'cookie_domain'); |
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$secure = Director::is_https() && Config::inst()->get('SilverStripe\\Control\\Session', 'cookie_secure'); |
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$session_path = Config::inst()->get('SilverStripe\\Control\\Session', 'session_store_path'); |
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$timeout = Config::inst()->get('SilverStripe\\Control\\Session', 'timeout'); |
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// Director::baseURL can return absolute domain names - this extracts the relevant parts |
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// for the session otherwise we can get broken session cookies |
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if (Director::is_absolute_url($path)) { |
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$urlParts = parse_url($path); |
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$path = $urlParts['path']; |
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if (!$domain) { |
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$domain = $urlParts['host']; |
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} |
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} |
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if (!session_id() && !headers_sent()) { |
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if ($domain) { |
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session_set_cookie_params($timeout, $path, $domain, $secure, true); |
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} else { |
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session_set_cookie_params($timeout, $path, null, $secure, true); |
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} |
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// Allow storing the session in a non standard location |
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if ($session_path) { |
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session_save_path($session_path); |
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} |
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// If we want a secure cookie for HTTPS, use a seperate session name. This lets us have a |
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// seperate (less secure) session for non-HTTPS requests |
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if ($secure) { |
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session_name('SECSESSID'); |
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} |
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if ($sid) { |
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session_id($sid); |
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} |
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session_start(); |
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$this->data = isset($_SESSION) ? $_SESSION : array(); |
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} |
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// Modify the timeout behaviour so it's the *inactive* time before the session expires. |
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// By default it's the total session lifetime |
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if ($timeout && !headers_sent()) { |
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Cookie::set(session_name(), session_id(), $timeout/86400, $path, $domain ? $domain |
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: null, $secure, true); |
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} |
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} |
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public function inst_destroy($removeCookie = true) |
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{ |
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if (session_id()) { |
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if ($removeCookie) { |
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$path = Config::inst()->get('SilverStripe\\Control\\Session', 'cookie_path') ?: Director::baseURL(); |
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$domain = Config::inst()->get('SilverStripe\\Control\\Session', 'cookie_domain'); |
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$secure = Config::inst()->get('SilverStripe\\Control\\Session', 'cookie_secure'); |
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Cookie::force_expiry(session_name(), $path, $domain, $secure, true); |
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} |
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session_destroy(); |
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// Clean up the superglobal - session_destroy does not do it. |
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// http://nz1.php.net/manual/en/function.session-destroy.php |
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unset($_SESSION); |
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$this->data = array(); |
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} |
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} |
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public function inst_set($name, $val) |
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{ |
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// Quicker execution path for "."-free names |
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if (strpos($name, '.') === false) { |
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$this->data[$name] = $val; |
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$this->changedData[$name] = $val; |
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} else { |
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$names = explode('.', $name); |
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// We still want to do this even if we have strict path checking for legacy code |
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$var = &$this->data; |
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$diffVar = &$this->changedData; |
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// Iterate twice over the names - once to see if the value needs to be changed, |
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// and secondly to get the changed data value. This is done to solve a problem |
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// where iterating over the diff var would create empty arrays, and the value |
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// would then not be set, inadvertently clearing session values. |
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foreach ($names as $n) { |
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$var = &$var[$n]; |
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} |
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if ($var !== $val) { |
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foreach ($names as $n) { |
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$diffVar = &$diffVar[$n]; |
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} |
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$var = $val; |
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$diffVar = $val; |
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} |
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} |
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} |
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public function inst_addToArray($name, $val) |
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{ |
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$names = explode('.', $name); |
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// We still want to do this even if we have strict path checking for legacy code |
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$var = &$this->data; |
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$diffVar = &$this->changedData; |
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foreach ($names as $n) { |
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$var = &$var[$n]; |
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$diffVar = &$diffVar[$n]; |
376
|
|
|
} |
377
|
|
|
|
378
|
|
|
$var[] = $val; |
379
|
|
|
$diffVar[sizeof($var)-1] = $val; |
380
|
|
|
} |
381
|
|
|
|
382
|
|
|
public function inst_get($name) |
383
|
|
|
{ |
384
|
|
|
// Quicker execution path for "."-free names |
385
|
|
|
if (strpos($name, '.') === false) { |
386
|
|
|
if (isset($this->data[$name])) { |
387
|
|
|
return $this->data[$name]; |
388
|
|
|
} |
389
|
|
|
return null; |
390
|
|
|
} else { |
391
|
|
|
$names = explode('.', $name); |
392
|
|
|
|
393
|
|
|
if (!isset($this->data)) { |
394
|
|
|
return null; |
395
|
|
|
} |
396
|
|
|
|
397
|
|
|
$var = $this->data; |
398
|
|
|
|
399
|
|
|
foreach ($names as $n) { |
400
|
|
|
if (!isset($var[$n])) { |
401
|
|
|
return null; |
402
|
|
|
} |
403
|
|
|
$var = $var[$n]; |
404
|
|
|
} |
405
|
|
|
|
406
|
|
|
return $var; |
407
|
|
|
} |
408
|
|
|
} |
409
|
|
|
|
410
|
|
|
public function inst_clear($name) |
411
|
|
|
{ |
412
|
|
|
$names = explode('.', $name); |
413
|
|
|
|
414
|
|
|
// We still want to do this even if we have strict path checking for legacy code |
415
|
|
|
$var = &$this->data; |
416
|
|
|
$diffVar = &$this->changedData; |
417
|
|
|
|
418
|
|
|
foreach ($names as $n) { |
419
|
|
|
// don't clear a record that doesn't exist |
420
|
|
|
if (!isset($var[$n])) { |
421
|
|
|
return; |
422
|
|
|
} |
423
|
|
|
$var = &$var[$n]; |
424
|
|
|
} |
425
|
|
|
|
426
|
|
|
// only loop to find data within diffVar if var is proven to exist in the above loop |
427
|
|
|
foreach ($names as $n) { |
428
|
|
|
$diffVar = &$diffVar[$n]; |
429
|
|
|
} |
430
|
|
|
|
431
|
|
|
if ($var !== null) { |
432
|
|
|
$var = null; |
433
|
|
|
$diffVar = null; |
434
|
|
|
} |
435
|
|
|
} |
436
|
|
|
|
437
|
|
|
public function inst_clearAll() |
438
|
|
|
{ |
439
|
|
|
if ($this->data && is_array($this->data)) { |
|
|
|
|
440
|
|
|
foreach (array_keys($this->data) as $key) { |
441
|
|
|
$this->inst_clear($key); |
442
|
|
|
} |
443
|
|
|
} |
444
|
|
|
} |
445
|
|
|
|
446
|
|
|
public function inst_getAll() |
447
|
|
|
{ |
448
|
|
|
return $this->data; |
449
|
|
|
} |
450
|
|
|
|
451
|
|
|
public function inst_finalize() |
452
|
|
|
{ |
453
|
|
|
$this->inst_set('HTTP_USER_AGENT', $this->userAgent()); |
454
|
|
|
} |
455
|
|
|
|
456
|
|
|
/** |
457
|
|
|
* Save data to session |
458
|
|
|
* Only save the changes, so that anyone manipulating $_SESSION directly doesn't get burned. |
459
|
|
|
*/ |
460
|
|
|
public function inst_save() |
|
|
|
|
461
|
|
|
{ |
462
|
|
|
if ($this->changedData) { |
|
|
|
|
463
|
|
|
$this->inst_finalize(); |
464
|
|
|
|
465
|
|
|
if (!isset($_SESSION)) { |
466
|
|
|
$this->inst_start(); |
467
|
|
|
} |
468
|
|
|
|
469
|
|
|
$this->recursivelyApply($this->changedData, $_SESSION); |
470
|
|
|
} |
471
|
|
|
} |
472
|
|
|
|
473
|
|
|
/** |
474
|
|
|
* Recursively apply the changes represented in $data to $dest. |
475
|
|
|
* Used to update $_SESSION |
476
|
|
|
* |
477
|
|
|
* @param array $data |
478
|
|
|
* @param array $dest |
479
|
|
|
*/ |
480
|
|
|
protected function recursivelyApply($data, &$dest) |
481
|
|
|
{ |
482
|
|
|
foreach ($data as $k => $v) { |
483
|
|
|
if (is_array($v)) { |
484
|
|
|
if (!isset($dest[$k]) || !is_array($dest[$k])) { |
485
|
|
|
$dest[$k] = array(); |
486
|
|
|
} |
487
|
|
|
$this->recursivelyApply($v, $dest[$k]); |
488
|
|
|
} else { |
489
|
|
|
$dest[$k] = $v; |
490
|
|
|
} |
491
|
|
|
} |
492
|
|
|
} |
493
|
|
|
|
494
|
|
|
/** |
495
|
|
|
* Return the changed data, for debugging purposes. |
496
|
|
|
* @return array |
497
|
|
|
*/ |
498
|
|
|
public function inst_changedData() |
499
|
|
|
{ |
500
|
|
|
return $this->changedData; |
501
|
|
|
} |
502
|
|
|
|
503
|
|
|
/** |
504
|
|
|
* Sets the appropriate form message in session, with type. This will be shown once, |
505
|
|
|
* for the form specified. |
506
|
|
|
* |
507
|
|
|
* @param string $formname the form name you wish to use ( usually $form->FormName() ) |
508
|
|
|
* @param string $message the message you wish to add to it |
509
|
|
|
* @param string $type the type of message |
510
|
|
|
*/ |
511
|
|
|
public static function setFormMessage($formname, $message, $type) |
512
|
|
|
{ |
513
|
|
|
Session::set("FormInfo.$formname.formError.message", $message); |
|
|
|
|
514
|
|
|
Session::set("FormInfo.$formname.formError.type", $type); |
|
|
|
|
515
|
|
|
} |
516
|
|
|
|
517
|
|
|
/** |
518
|
|
|
* Is there a session ID in the request? |
519
|
|
|
* @return bool |
520
|
|
|
*/ |
521
|
|
|
public static function request_contains_session_id() |
|
|
|
|
522
|
|
|
{ |
523
|
|
|
$secure = Director::is_https() && Config::inst()->get('SilverStripe\\Control\\Session', 'cookie_secure'); |
524
|
|
|
$name = $secure ? 'SECSESSID' : session_name(); |
525
|
|
|
return isset($_COOKIE[$name]) || isset($_REQUEST[$name]); |
526
|
|
|
} |
527
|
|
|
|
528
|
|
|
/** |
529
|
|
|
* Initialize session. |
530
|
|
|
* |
531
|
|
|
* @param string $sid Start the session with a specific ID |
532
|
|
|
*/ |
533
|
|
|
public static function start($sid = null) |
534
|
|
|
{ |
535
|
|
|
self::current_session()->inst_start($sid); |
536
|
|
|
} |
537
|
|
|
|
538
|
|
|
/** |
539
|
|
|
* Destroy the active session. |
540
|
|
|
* |
541
|
|
|
* @param bool $removeCookie If set to TRUE, removes the user's cookie, FALSE does not remove |
542
|
|
|
*/ |
543
|
|
|
public static function destroy($removeCookie = true) |
544
|
|
|
{ |
545
|
|
|
self::current_session()->inst_destroy($removeCookie); |
546
|
|
|
} |
547
|
|
|
} |
548
|
|
|
|
Instead of super-globals, we recommend to explicitly inject the dependencies of your class. This makes your code less dependent on global state and it becomes generally more testable: