如何在不验证其余属性/列的情况下验证和更新1个属性/列？

Question

I want my users to be able to update their email addresses, if they authenticate themselves.

My code looks something like this...

    @user = User.find_by_email(params[:user][:old_email].downcase)

    if @user
        if @user.authenticate(params[:user][:password])
            @user.email = params[:user][:email]

            if @user.update_attributes(email: params[:user][:email])

Something along those lines. Basically the params are the old_email, the email which the user wants to change to, and their password. We pull the record that matches their old_email (current email). Then we verify the password matches. If so, we want to change the email and the email only, IF of course the email meets the criteria in our model for the :email column.

The problem I'm having is, when I get to @user.update_attributes(em... I get the following error

"Password is too short (minimum is 6 characters)"

I don't want it to verify on password, password should not even be involved in the update whatsoever. I'm only interested in the changing the email here. I want validation only on the email field, and none of the others, and I only want to update the email field. How can I achieve this?

Answer 1

You can update specific column by #update_columns . It updates the attributes directly in the database issuing an UPDATE SQL statement and sets them in the receiver.

It will skip validations and callbacks .

@user.update_columns(email: params[:user][:email])

Remember to sanitise the email address before updating.

Validation belongs in the model but as you need to validate in controller, define a private action:

private
  def valid_email?(email)
    VALID_EMAIL_REGEX = /\A[\w+\-.]+@[a-z\d\-.]+\.[a-z]+\z/i
    email.present? && (email =~ VALID_EMAIL_REGEX)
  end

Then your condition check would be:

if @user.authenticate(params[:user][:password]) && valid_email?(params[:user][:email])