Rails Email Validation Based on Params

Question

I have two registration forms: one that can register with any email address and the other with just one specific domain. How to allow that from the User.rb model?

Something like this may work:

validates_format_of :email, :with => /.io/

But because I have two registration forms and the url for that form has an id of 2:

validates_format_of :email, :with => /.io/ if params[id] == 2

I do understand that params is not available in the model but based on what I want to achieve, how to accomplish this?

Basically form with id = 1 can register with any email. Form with id = 2 can only register with a .io email address (domain).

Jordan Running · Accepted Answer · 2015-12-14 20:10:16Z

1

This sounds like a good use for validation contexts. A validates* method can accept an :on option, which is the name of the "context" in which the validation will be triggered; for example:

validates_format_of :email, :with => /\.io\z/, on: :restricted_email

This validation will only be triggered if the option context: :restricted_email is passed to the save or save! method. Here's how you might use it in your controller:

def create
  @user = User.new(params[:user])

  if params[:id] == 2
    @user.save!(context: :restricted_email)
  else
    @user.save!
  end
end

Here's a good blog post on the topic: http://blog.arkency.com/2014/04/mastering-rails-validations-contexts/

edited Dec 14, 2015 at 20:10

answered Dec 14, 2015 at 19:25

Jordan Running

107k18 gold badges193 silver badges189 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

Sylar Over a year ago

Error:

The provided regular expression is using multiline anchors (^ or $), which may present a security risk. Did you mean to use \A and \z, or forgot to add the :multiline => true option?

Sylar Over a year ago

Jordon, one last question. With your code, how easily to add more domain to the regex?

Jordan Running Over a year ago

It's pretty easy to express domain names in a regular expression, e.g. /\.(com|edu|io|co\.uk)\z/.

Jordan Running Over a year ago

An easy way to play around with regular expressions in Ruby is Rubular.com: rubular.com/r/QNgfdyo9sH

irbanana · Accepted Answer · 2015-12-14 19:24:47Z

1

You could add an attribute to the model that would indicate which form registration was coming from, like :registered_io, sent to your model through a hidden field in the form

#...
<%= f.hidden_field :registered_io, value="true" # or false %>

Then in your model you could just do an

validates :format_of_io_email_should if self.registered_io 
validates :format_of_universal_email_should if !self.registered_io

def format_of_io_email_should
 # regex ahoy or whatever
end
def format_of_universal_email_should
# same same but different
end

Don't forget to run your migrations to store the attribute, too!

$ rails migration add_column_registered_io_to_user registered_io:boolean

Also don't forget to allow :registered_io in the strong params in the controller.

answered Dec 14, 2015 at 19:24

irbanana

91112 silver badges20 bronze badges

3 Comments

user229044 Over a year ago

This is the better option, in my opinion. Whatever criteria you have for restricting a user to .io email addresses, you are probably going to want to maintain that context after the user is created. Otherwise you have no way of knowing whether an existing user with a .io email address belonged to the given group or not.

Sylar Over a year ago

I'm getting undefined method for registered_to from the model.

irbanana Over a year ago

registered_to or registered_io? Head in to $ rails console to check it out.

Collectives™ on Stack Overflow

Rails Email Validation Based on Params

2 Answers 2

4 Comments

3 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

4 Comments

3 Comments

Your Answer

Sign up or log in

Post as a guest

Related