Socket ID stability and connection state recovery

[fjeldstad]

I know that the recovered property of the client-side socket instance indicates whether the last connection was a successful recovery. And I know that when a connection is recovered, the socket ID naturally stays the same. But is the inverse true? That is, if socket ID is the same before and after a reconnect, does that guarantee that the connection was recovered? Or are there scenarios where the socket ID would remain the same but the connection was not fully recovered?

[darrachequesne]

Yes, if the socket ID stays the same, then it means that the connection was fully recovered.

Reference: https://socket.io/docs/v4/connection-state-recovery#how-it-works-under-the-hood

[fjeldstad]

Thanks for a quick response! I think it would also not hurt if the docs confirmed this more explicitly, perhaps in the example describing connection state recovery.