Better way of validating a certain hostname in URI

[Apidcloud]

Support plan

• is this issue currently blocking your project? (yes/no): no
• is this issue affecting a production system? (yes/no): no

Context

• node version: 16.9.1
• module version: 17.4.2
• environment (e.g. node, browser, native): node
• used with (e.g. hapi application, another framework, standalone, ...): standalone
• any other relevant information:

How can we help?

This is related to https://github.com/sideway/joi/issues/1965. I am wondering if there is a way of validating whether a given URI has a certain hostname. This would be useful, for instance, to validate social media URIs (e.g., instagram, facebook, twitter). In the thread https://github.com/sideway/joi/issues/1965 it is mentioned that the portion can be verified through some new option introduced in v16, but I couldn't figure out how to do it yet. For now I am relying on regex (see example below), though one could have a custom validation step (using node URL.hostname).

facebook: Joi.string()
  .uri({
    scheme: 'https',
	domain: { 
		// is there a way of checking the hostname here?
	}
   })
  .regex(/https:\/\/(www\.)?facebook\.com\/.*/)
  .optional(),

[BolajiOlajide]

@hueniverse I'll love to help out with this, let me know if it's something you think I can help with. Also, let me know if you've got any approach you'd like to me employ.

Thanks.