Rails 3 - how to skip validation rule? - ruby-on-rails

Question

I have for the registration form this validation rule:
validates :email,
:presence => {:message => 'cannot be blank.'},
:allow_blank => true,
:format => {
:with => /\A[A-Za-z0-9._%+-]+#[A-Za-z0-9.-]+\.[A-Za-z]+\z/,
:message => 'address is not valid. Please, fix it.'
},
:uniqueness => true
This rule check, if a user fill into the registration form email address (+ its correct format).
Now I am trying to add the opportunity to log in with using Twitter. Twitter doesn't provide user's email address.
How to skip in this case the validation rule above?

Answer 1

You can skip validation while saving the user in your code. Instead of using user.save!, use user.save(:validate => false). Learnt this trick from Railscasts episode on Omniauth

Answer 2

I'm not sure whether my answer is correct, just trying to help.
I think you can take help from this question. If i modify the accepted answer for your question, it will be like (DISCLAIMER: I could not test the following codes as env is not ready in the computer i'm working now)
validates :email,
:presence => {:message => 'cannot be blank.', :if => :email_required? },
:allow_blank => true,
:format => {
:with => /\A[A-Za-z0-9._%+-]+#[A-Za-z0-9.-]+\.[A-Za-z]+\z/,
:message => 'address is not valid. Please, fix it.'
},
:uniqueness => true
def email_required?
#logic here
end
Now, you update the email_required? method to determine whether it is from twitter or not! If from twitter, return false otherwise true.
I believe, you need use same :if for the :uniqueness validator too. otherwise it will. Though, i'm not sure too :(. Sorry

Answer 3

Skipping Individual Validations
Skipping individual validations requires a bit more work. We need to create a property on our model called something like skip_activation_price_validation:
class Product < ActiveRecord::Base
attr_accessor :skip_activation_price_validation
validates_numericality_of :activation_price, :greater_than => 0.0, unless: :skip_activation_price_validation
end
Next we will set the property to true any time we want to skip validations. For example:
def create
#product = Product.new(product_params)
#product.skip_name_validation = true
if #product.save
redirect_to products_path, notice: "#{#product.name} has been created."
else
render 'new'
end
end
def update
#product = Product.find(params[:id])
#product.attributes = product_params
#product.skip_price_validation = true
if #product.save
redirect_to products_path, notice: "The product \"#{#product.name}\" has been updated. "
else
render 'edit'
end
end

Answer 4

You seem to be doing two separate validations here:
If a user provides an email address, validate it's format and uniqueness
Validate the presence of an email address, unless it's a twitter signup
I would do this as two separate validations:
validates :email,
:presence => {:message => "..."},
:if => Proc.new {|user| user.email.blank? && !user.is_twitter_signup?}
validates :email,
:email => true, # You could use your :format argument here
:uniqueness => { :case_sensitive => false }
:unless => Proc.new {|user| user.email.blank?}
Additional info: validate email format only if not blank Rails 3

Answer 5

The best way would be:
It would validate the email when the user is not signed in from twitter as well as skip email validation when signed from twitter.
validates :email,
:presence => {:message => 'cannot be blank.'},
:allow_blank => true,
:format => {
:with => /\A[A-Za-z0-9._%+-]+#[A-Za-z0-9.-]+\.[A-Za-z]+\z/,
:message => 'address is not valid. Please, fix it.'
},
:uniqueness => true
unless: Proc.new {|user| user.is_twitter_signup?}