WindowsAzureSessionHandler 的 Read 方法

windowsazuresessionhandler.php

/**
 * Callback function for session handler. It's invoked while the session data is being read.
 *
 * @param $sessionId The session ID.
 *
 * @return string The session data. It will retrun empty string if the session doesn't exist.
 */
public function read($sessionId) {
  try {
    // try to retrieve the session content first to see if it exists
    $result = $this->_tableRestProxy->getEntity($this->_sessionContainer, $this->_sessionContainerPartition, $sessionId);
    // get the entity instance
    $entity = $result->getEntity();
    // deflat the serialized data
    return unserialize(base64_decode($entity->getPropertyValue('data')));
  } catch (ServiceException $e) {
    // the entity doesn't exist, return empty string according to the spec:
    //   http://www.php.net/manual/en/sessionhandlerinterface.read.php
    return '';
  }
}