How to participate in the authentication information for websocket connection custom authentication

Pulsar turns on custom authentication. When my custom authentication gets the parameters, it will query the database. How to pass the authentication parameters using the websocket connection, and how does the server get the parameters

The issue mentions Pulsar custom authentication and WebSocket connections but names no file, test, or entry point. Start by tracing the WebSocket authentication flow and its parameter handling, then document how clients pass authentication parameters and how the server receives them; done means a clear, tested usage explanation.

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