Validation for URL/Domain using Regex? (Rails)

Question

I am trying to create a validation that checks to make sure a domain/url is valid for example \"test.com\"

def valid_domain_name?
  domain_name = domain.spli         


        

Answer 1

Using Brian Ray's answer above which I think answers the question (domain not url) and updating it for Rails 4.

/\A[a-z0-9]+([\-\.]{1}[a-z0-9]+)*\.[a-z]{2,5}\z/ix