Add data type for urls

[fnando]

It would be nice to have a data type url, which validates the scheme against http/https. It would be nicer if this extension had support for hostname validation against TLDs.

[petere]

You can create a domain that checks that scheme part of the value. What else would you want to do beyond that?

For TLD verification, see petere/pgemailaddr#1.

[fnando]

Yeah, I'm using a CHECK for that. The problem is that you have to do something like CHECK (uri_scheme(site::uri) IS NOT NULL AND uri_scheme(site::uri) ~ '^https?$'), which is kinda cumbersome.

[petere]

Well, if you use a domain, you only have to do it once. (And you don't need the IS NOT NULL check.)