[QUESTION] How can I communicate between HTTP server and WebSocket Server?

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### Describe your question
I have my Hyperf application serving both HTTP and WebSocket traffics. The WebSocket maintains a list of client connections in-memory. I would want to have an HTTP endpoint that returns the number of clients that are connected. Is there a way to achieve this without having to store data out of the application (e.g. Redis, MySQL, etc).

I was hoping there is a way the HTTP and the WebSocket server can establish communication since they are basically within the same app. If so, how can I achieve this? If not, what are your recommendations / alternatives for this?

Thank you very much!