Closing callback for a node client in ClusterClient

[lzakharov]

Good day!

Is there any option to set the closing callback for a node client in ClusterClient?

Use Case I want to start metrics collection process on every new node client creation and stop it when the node client is removed for some reason. To stop the process I have to provide a callback somehow. To start the process I can use ClusterClient.OnNewNode.

Ideas One solution that comes to my mind is to add a callback to the return function that the ClusterClient.OnNewNode accepts:

func (c *ClusterClient) OnNewNode(fn func(rdb *Client) func()) {
    ...
}

This callback should be added to the clusterNode and called inside it's Close method.

However, to avoid breaking backward compatibility, it's possible to add a separate method for ClusterClient, such as OnNewNodeWithClose.

Another idea is to expand the redis.Hook interface to provide additional CloseHook method.

Thanks for any feedback in advance.

[lzakharov]

Another option is to make the baseClient.onClose configurable.