Called by Lightstreamer Kernel through the Remote Server to ask for the allowance of a publishing Mode for an Item. A publishing Mode can or cannot be allowed depending on the User. The Metadata Adapter should ensure that conflicting Modes are not both allowed for the same Item (even for different Users), otherwise some Requests will be eventually refused by Lightstreamer Kernel. The conflicting Modes are MERGE, DISTINCT and COMMAND.
This method runs in the Server thread pool specific for the Data Adapter that supplies the involved items, if defined.
Function IsModeAllowed(user As string, item As string, mode As Mode) As bool