Socket.io socket data availability after disconnect

When the socket disconnect event is fired with socket.io (node.js), for how long will t开发者_开发问答he socket's data still be available?

If I have a store (like redis) that asynchronously returns data, is it safe to still perform lookups?

I need to get all data of a socket in order to save the socket's state when it disconnects.

Thanks a lot.

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The server has 'client store expiration' option, it's set to 15 (sec) by default.