How concatenate a string in Rails before saving to the database, for the purpose of adding the domain to an email address

Question

I am currently trying to create a sign up form that takes a string containing

"first_last" and adds "@exampledomain.com" to create "first_last@exampledomain.com" and write it to the database.

However, if a user types the full domain, I don't want to add it twice, so I need a method that checks to see if "@exampledomain.com" is already present. I don't want to end up with "first_last@exampledomain.com@exampledomain.com" as it will fail to validate and annoy users.

So far, I have put this into my user model:

before_validation { concatenate_email }

VALID_EMAIL_REGEX = /[a-zA-Z]{1,}[_]{1}[a-zA-Z]{1,}@exampledomain.com/i

validates :email, presence:   true,
                format:     { with: VALID_EMAIL_REGEX },
                uniqueness: { case_sensitive: false }

def concatenate_email
  @mail = self.email.match('@asamacm.com')
  if @mail = nil
    self.email.concat('@asamacm.com')
  else
  end
end

I am new to rails and ruby, so I apologize if my terms are incorrect.

Answer 1

Here is another way of doing it

def concatenate_email
  self.email.concat('@asamacm.com') unless self.email =~ /@asamacm.com/
end