Official email validation in Ruby - ruby-on-rails

Question

I only want official email addresses such as xyz#company.com to sign up on my service rather than other generic email addresses such as gmail.com or Yahoo mail.com
Is there a ruby gem to achieve this kind of email validation? If not, how to make this happen?

Answer 1

You could write a custom validation in the appropriate model as shown here: http://www.rails-dev.com/custom-validators-in-ruby-on-rails-4
The basic idea in the article is as follows:
Make your validation method, and put it in a new directory called 'validators'
# app/validators/email_validator.rb
class EmailValidator < ActiveModel::EachValidator
def validate_each(record, attribute, value)
unless value =~ /\A([^#\s]+)+#yourdomain.com\z/i
record.errors[attribute] << (options[:message] || "wrong email address")
end
end
end
(I have not tested this regex! Please use something like http://rubular.com/ and plug in your own email domain pattern to make sure it's working correctly.)
Then make sure Rails knows to load the new validators directory:
# config/application.rb
config.autoload_paths += %W["#{config.root}/app/validators/"]
Then add the new validation (email) to the appropriate model:
#MyModel.rb
validates :my_email_field, email: true

Answer 2

There is a free MailboxValidator web service that you can perform real-time email address validation in Ruby.
https://github.com/MailboxValidator/mailboxvalidator-ruby
require "mailboxvalidator_ruby"
apikey = "MY_API_KEY"
email = "example#example.com"
mbv = MailboxValidator::MBV.new()
mbv.apikey = apikey
mbv.query_single(email)
if mbv.error != nil
puts "Error: #{mbv.error}"
elsif mbv.result != nil
puts "email_address: #{mbv.result.email_address}"
puts "domain: #{mbv.result.domain}"
puts "is_free: #{mbv.result.is_free}"
puts "is_syntax: #{mbv.result.is_syntax}"
puts "is_domain: #{mbv.result.is_domain}"
puts "is_smtp: #{mbv.result.is_smtp}"
puts "is_verified: #{mbv.result.is_verified}"
puts "is_server_down: #{mbv.result.is_server_down}"
puts "is_greylisted: #{mbv.result.is_greylisted}"
puts "is_disposable: #{mbv.result.is_disposable}"
puts "is_suppressed: #{mbv.result.is_suppressed}"
puts "is_role: #{mbv.result.is_role}"
puts "is_high_risk: #{mbv.result.is_high_risk}"
puts "is_catchall: #{mbv.result.is_catchall}"
puts "mailboxvalidator_score: #{mbv.result.mailboxvalidator_score}"
puts "time_taken: #{mbv.result.time_taken}"
puts "status: #{mbv.result.status}"
puts "credits_available: #{mbv.result.credits_available}"
puts "error_code: #{mbv.result.error_code}"
puts "error_message: #{mbv.result.error_message}"
end