This class sends data to subscribed users.
Attention: for safety purposes, users cannot subscribe to a channel via JS, so that, for example, not to be able to read someone's else private article and etc. That is why parameters from $_GET, $_POST, $_REQUEST cannot be used in the subscription tag, so that a wrongdoer would not be able to subscribe to content, access to which is restricted for him/her.
|Method||DEscription||Available from version|
|Add||Subscription to commands.|
|Delete||Deletion of subscription.|
|AddToStack||Sending data to subscribed users.|
|GetUserList||Retrieving list of user, subscribed to a certain tag.|