Allow address.parse() to reject addresses with local hostnames

[grvsmth]

address.parse() currently accepts addresses with a single-part domain as used for a local mail host, e.g. bleah@example. I am currently working on a use case where we would only want to send to Internet addresses, like bleah@example.com or bleah@foo.example.com. It would be useful to have an option to reject addresses with single-part domains.

[horkhe]

It seems to be too use case specific to be included as a parser option. I can think of many similar specific use cases e.g.: do not allow domains of 3rd, 4th, Xth level; do not allow domains from specific top level domains; do not allow domains from a certain geo region... All that seems like a higher level of abstraction that lays out of the scope of the email address syntax parsing.

In your case the solution is as simple as:

addr = parse('bleah@example')
if addr and '.' in add.hostname:
    // bingo
else:
    // invalid address or local domain 

So I think it is out of the scope of Flanker and should not be implemented. @b0d0nne11 what do you think?

[b0d0nne11]

I would agree. There maybe other users of the library that have a valid use case to send to bob@localhost for example.

[grvsmth]

To clarify, Brendan, I am not suggesting we remove the validation of addresses like blah@example. I am suggesting we add the option to filter out addresses with that form.

[grvsmth]

Thanks for your feedback, Maxim. I do not see the other use cases you mention as being anywhere near as common, and I hope you will consider adding this option. In the meantime I will add a check in my script along the lines you suggest.

[b0d0nne11]

Actually validate_address should already reject blah@example and bob@localhost because they don't have a valid TLD. It will also optionally lookup the MX servers and try to connect to them but that can be turned off with the skip_remote_checks kwarg. We use that in our messages API after parsing to filter out these kinds of addresses.

[grvsmth]

We don't really want to go to the trouble of calling validate_address() when all we want is to check the form of the address, but thanks.