Websocket
A WebSocket session keeps one connection open in both directions, which suits devices that need low-latency two-way messaging without re-establishing a connection for every message.
Connecting
| Port | 9955 |
| Path | /south/v80/sessions/{device.id} |
| Authentication | X-ApiKey, required |
The API key can travel either way, whichever your WebSocket client makes easier:
As a header of the HTTP request that establishes the connection.
As a URL parameter named X-ApiKey:
Replace your-device-id and your-api-key with the values of your environment.
What travels over the session
The messages themselves are shaped by a connector function: the URI of the
session is matched against the function’s southCriterias with the wss:// scheme, and the function
decides what to do with each incoming message. To send a message back down an already open connection, use
the WebSocket JavaScript API.
The contextParams your script receives include the session’s uri, its relative path and the
sessionIp, which is how a single function can serve several session paths and tell them apart.