If server is closing, then HELO etc commands should not be accepted

[titanism]

Here we have

smtp-server/lib/smtp-connection.js

Line 406 in 2bd0975

_onCommand(command, callback) {

commands being parsed. However if the server is shutting down, commands such as HELO will still be accepted. Is there a way to add this feature, similar to how we can process onData, onRcptTo, etc? Then we could add if (this._closeTimeout) return setImmediate(() => callback(new Error('Server is shutting down'));.

[titanism]

Title updated