ws4py provides a high-level, yet simple, interface to provide your application with WebSocket support. It is simple as:
from ws4py.websocket import WebSocket
The :class:`WebSocket <ws4py.websocket.WebSocket>` class should be sub-classed by your application. To the very least we suggest you override the :func:`received_message(message) <ws4py.websocket.WebSocket.received_message>` method so that you can process incoming messages.
For instance a straightforward echo application would look like this:
class EchoWebSocket(WebSocket): def received_message(self, message): self.send(message.data, message.is_binary)
Other useful methods to implement are:
- :func:`opened() <ws4py.websocket.WebSocket.opened>` which is called whenever the WebSocket handshake is done.
- :func:`closed(code, reason=None) <ws4py.websocket.WebSocket.closed>` which is called whenever the WebSocket connection is terminated.
You may want to know if the connection is currently usable or :attr:`terminated <ws4py.websocket.WebSocket.terminated>`.
At that stage, the subclass is still not connected to any data source. The way ws4py is designed, you don't necessarily need a connected socket, in fact, you don't even need a socket at all.
>>> from ws4py.messaging import TextMessage >>> def data_source(): >>> yield TextMessage(u'hello world') >>> from mock import MagicMock >>> source = MagicMock(side_effect=data_source) >>> ws = EchoWebSocket(sock=source) >>> ws.send(u'hello there')