SignalR: Is it necessary to remove the connection id from group OnDisconnect()?
signalr
Solution
According to the statement here, you don't need to remove connections from groups:
You should not manually remove the user from the group when the user disconnects. This action is automatically performed by the SignalR framework.
When a connection subscribes to a topic (which happens when you add the connection to a group), it receives a disposable which will remove the subscription when disposed (which means the connection isn't in the group anymore). This is triggered when a connection disconnects and is removed.
Problem
The tutorials only covered adding a connection ID to the group on `OnConnected()`, but what about cleaning it up on `OnDisconnect()`? After a permanent loss of connectivity, a client is given a new connection ID. What happens to its old connection ID in the group list? Is it automatically cleaned up? or is it scalable enough that I don't have to worry about it?