valid email and url

valid_email_valid_url.rb

# gratuitously lifted from Vito Botta at http://vitobotta.com/sinatra-contact-form-jekyll/

require 'resolv'

def valid_email?(email)
  if email =~ /^[a-zA-Z][\w\.-]*[a-zA-Z0-9]@[a-zA-Z0-9][\w\.-]*[a-zA-Z0-9]\.[a-zA-Z][a-zA-Z\.]*[a-zA-Z]$/
    domain = email.match(/\@(.+)/)[1]
    Resolv::DNS.open do |dns|
        @mx = dns.getresources(domain, Resolv::DNS::Resource::IN::MX)
    end
    @mx.size > 0 ? true : false
  else
    false
  end
end

def valid_url? url
  return true if url == "http://"
  !(url =~ /^(http|https):\/\/[a-z0-9]+([\-\.]{1}[a-z0-9]+)*\.[a-z]{2,5}(:[0-9]{1,5})?(\/.*)?$/ix).nil?
end