validate and update single attribute rails

Question

I have the following in my user model

attr_accessible :avatar, :email

validates_presence_of :email
has_attached_file :avatar # paperclip

validates_attachment_s         


        

Answer 1

I am assuming you need this, because you have a multi-step wizard, where you first upload the avatar and the e-mail is filled in later.

To my knowledge, with your validations as they are, I see no good working solution. Either you validate all, or you update the avatar without validations. If it would be a simple attribute, you could check if the new value passes the validation seperately, and then update the model without validations (e.g. using update_attribute).

I can suggest two possible alternative approaches:

• either you make sure that the e-mail is always entered first, which I believe is not a bad solution. And then, with each save, the validation is met.
• otherwise, change the validation. Why would you declare a validation on a model, if there are records in the database that do not meet the validation? That is very counter-intuitive.

So I would propose something like this:

validate :presence_of_email_after_upload_avatar

def presence_of_email_after_upload_avatar
  # write some test, when the email should be present
  if avatar.present?
    errors.add(:email, "Email is required") unless email.present?
  end
end

Hope this helps.