Validate email address properly

app/models/concerns/email_validatable.rb

@@ -0,0 +1,15 @@
+require 'mail'
+
+module EmailValidatable
+  extend ActiveSupport::Concern
+
+  class EmailValidator < ActiveModel::EachValidator
+    def validate_each(record, attribute, value)
+      begin
+        a = Mail::Address.new(value)
+      rescue Mail::Field::ParseError
+        record.errors[attribute] << (options[:message] || "is not a valid address")
+      end
+    end
+  end
+end