Implement DSN

[blacksph3re]

As described in rcf3461 smtp supports delivery status notifications. It would be nice to have a way to check on DSNs for an email to see if it failed to deliver

[kdisneur]

That's a good idea but I don't know if it's possible to implement.

We rely on gen_smtp to send the emails and I don't see any keywords coming from the DSN spec anywhere (RET, NOTIFY,...) in the repository.

I would suggest to contact the gen_smtp maintainer. I can see an open issue there but no replies.

[tgautier]

Closed as there is still no sign from
gen-smtp/gen_smtp#161 on the support of DSN.

Feel free to reopen this issue if support is coming.

[mworrell]

Passing by, as this is referring to an issue in gen_smtp.

What features are you looking for? An option to specify DSN when sending emails?