addWebsocketExtension

Add support for a WebSocket extension of the given @extension_type.

When a WebSocket client requests an extension of @extension_type, a new class@WebsocketExtension of type @extension_type will be created to handle the request.

Note that class@WebsocketExtensionDeflate is supported by default, use method@Server.remove_websocket_extension if you want to disable it.

Parameters