vapor-docs/3.0/docs/websocket/websocket.md

WebSocket

WebSockets are a type of connection that can be instantiated by upgrading an existing HTTP/1.1 connection. They're used to dispatch notifications and communicate real-time binary and textual Data.

Vapor 3 supports both WebSocket Client and Server.

Using websockets

WebSockets are interacted with using binary streams or text streams.

Errors

Any error in a WebSocket will close the connection.