Wrap Listener to also return dynamiclistener config

[vitorsavian]

Proposed Changes

• Use a wrapper for easy access to the listener config

Why

• K3s need to regenerate leaf certs with hot reload without the need for restart
• the main idea is to also return the config that was used for creating the listener, since the best way to regenerate/reload the dynamic listener cert on demand is to use the listener that was created in NewListenerWithChain initial setup.

[brandond]

Couple nits.

How do you envision this being called from the K3s side? You're just planning on calling listener.RegenerateCerts directly from K3s?

If you add the ability to do that directly, you might as well remove the RegenerateCerts callback that can be set in the config, but is only called once from NewListenerWithChain

dynamiclistener/listener.go

Line 146 in 8fd666b

RegenerateCerts func() bool

dynamiclistener/listener.go

Lines 88 to 91 in 8fd666b

	if config.RegenerateCerts != nil && config.RegenerateCerts() {
	if err := dynamicListener.regenerateCerts(); err != nil {
	return nil, nil, err
	}

[brandond]

Any plans to address the duplication of function with the existing RegenerateCerts callback? I think we should just get rid of it since K3s is the only user that I am aware of, and this would replace that.

[vitorsavian]

I thought we would have another user that used dynamic listener, but since we are the only users, I will remove that.

[brandond]

We are actually the only users of NewListener/NewListenerWithChain - other rancher projects all just use server.ListenAndServe

[brandond]

@vitorsavian do we still need this?