Add Noop method to the Session interface

[kayrus]

And add error pointer to the Reset method

Noop() is supposed to be used to test the connection state

[emersion]

I'm not sure I understand:

• This PR just adds a new method but never calls it.
• NOOP always make the server reply with OK immediately. The backend doesn't need to be involved in this.

[kayrus]

This PR just adds a new method but never calls it.

it is a new method like others. it is not necessary to call it inside this package. the PR just exposes it in Sessions interface.

NOOP always make the server reply with OK immediately. The backend doesn't need to be involved in this

I don't understand the question. It is for the client.

[emersion]

Session is a type used by servers only.

[kayrus]

It is used by proxy. Proxy is kinda client-server.

[emersion]

Sorry, I don't understand what you're trying to do, but I'm not going to merge this change, it doesn't make sense to me.

[kayrus]

@emersion Your questions don't make sense :\ This PR just extends the session interface. Session interface is used in https://github.com/emersion/go-smtp-proxy. Each session represents a connection. In order to keep running long living connections I need to periodically execute NOOP command. If the NOOP fails, the connection needs to be reestablished.

[kayrus]

@emersion I see you just archived the https://github.com/emersion/go-smtp-proxy repo. At least google cache shows that it was still active on 25th of April. Even though, I still would like to have a Noop method in upstream. I hope you can review the PR once again and merge it.

[emersion]

I don't have any more free time to spend on your issue.