| 35 | |
| 36 | @gen.coroutine |
| 37 | def _execute(self, transforms, *args, **kwargs): |
| 38 | self._transforms = transforms |
| 39 | # Websocket only supports GET method |
| 40 | if self.request.method != "GET": |
| 41 | self.set_status(405) |
| 42 | self.set_header("Allow", "GET") |
| 43 | self.set_header("Connection", "Close") |
| 44 | self.finish("WebSocket only supports GET requests.") |
| 45 | return |
| 46 | |
| 47 | # Upgrade header should be present and should be equal to WebSocket |
| 48 | if self.request.headers.get("Upgrade", "").lower() != "websocket": |
| 49 | self.set_status(400) |
| 50 | self.set_header("Connection", "Close") |
| 51 | self.finish("Can \"Upgrade\" only to \"WebSocket\".") |
| 52 | return |
| 53 | |
| 54 | # Connection header should be upgrade. Some proxy servers/load balancers |
| 55 | # might mess with it. |
| 56 | headers = self.request.headers |
| 57 | connection = map(lambda s: s.strip().lower(), headers.get("Connection", "").split(",")) |
| 58 | if "upgrade" not in connection: |
| 59 | self.set_status(400) |
| 60 | self.set_header("Connection", "Close") |
| 61 | self.finish("\"Connection\" must be \"Upgrade\".") |
| 62 | return |
| 63 | |
| 64 | yield super(SockJSWebSocketHandler, self)._execute(transforms, *args, **kwargs) |