WebSocket API support in Opera Presto 2.11

W3C reference

W3C WebSocket API

Opera Presto offers support for the W3C WebSocket API as defined in the following data table.

Important notes:

• WebSocket support in Opera Presto is disabled by default. This is due to flaws which can be exploited in the current WebSocket protocol.
• Opera does not support subprotocol negotiation; the "protocols" argument can only be a single string.

WebSocket interface

Constructor	Attributes	Methods	Comment	Support
WebSocket()	url readyState protocol bufferedAmount	send(data) close()	This interface enables web applications to maintain bidirectional communications with server-side processes. The protocol attribute is not supported. Array as protocols argument in WebSocket constructor is not supported	Partial

CloseEvent interface

Constructor	Attributes	Methods	Comment	Support
CloseEvent	wasClean	initCloseEvent()	When the WebSocket connection is closed, possibly cleanly, the user agent must create an event that uses the CloseEvent interface, with the event name close, which does not bubble, is not cancelable, has no default action, and whose wasClean attribute is set to true if the connection closed cleanly, and false if otherwise.	Yes

Event handlers

Event handler	Event type	Support
onopen	open	Yes
onmessage	message	Yes
onerror	error	Yes
onclose	close	Yes