Test preconditions are not checked when using direct URL

[WKobes]

If you enter an invalid URL, like kasfjajfkljklaw.safjhsfhaka, in the website or mail test, the form rejects the URL with message:

The given domain is invalid!
Explanation: An A and/or AAAA record is necessary for the website test, and a SOA record for the email test.

However, directly navigating to the test URL bypasses the check. https://internet.nl/mail/kasfjajfkljklaw.safjhsfhaka/ https://internet.nl/site/kasfjajfkljklaw.safjhsfhaka/

Because the validation is only executed on the index/POST submission of both tests:

https://github.com/internetstandards/Internet.nl/blob/fa4a64001d62faf0ed0e2cdd57432bd450f95e2f/checks/views/domain.py#L37

Another interesting observation is that DNSSEC appears to pass for domains with unexisting TLD, but I am not sure if that should be regarded as an issue as these domains should not be tested in the first place.