Undefined method confirmed_at when using Devise

Question

I'm getting the following error when trying to use the :confirmable module of Devise:

NameError (undefined local variable or method `confirmed_at' for #<AdminUser:0x007f27841d0f30>)

My model:

class AdminUser < ActiveRecord::Base
  # Include default devise modules. Others available are:
  # :confirmable, :lockable, :timeoutable and :omniauthable
  devise :database_authenticatable,:recoverable, :rememberable, :trackable, :validatable, :confirmable

  after_create { |admin| admin.send_reset_password_instructions }
  def password_required?
    new_record? ? false : super
  end
end

I want to send a confirmation email when AdminUser is created.

Answer 1

It is not enough to merely add the :confirmable option in the model, you'll also need to add the columns required by Devise into your database table.

Assuming you are using a model AdminUser:

class AddConfirmableToDevise < ActiveRecord::Migration
  def self.up
    add_column :admin_users, :confirmation_token,   :string
    add_column :admin_users, :confirmed_at,         :datetime
    add_column :admin_users, :confirmation_sent_at, :datetime
    add_column :admin_users, :unconfirmed_email,    :string

    add_index  :admin_users, :confirmation_token, :unique => true
  end

  def self.down
    remove_index  :admin_users, :confirmation_token

    remove_column :admin_users, :unconfirmed_email
    remove_column :admin_users, :confirmation_sent_at
    remove_column :admin_users, :confirmed_at
    remove_column :admin_users, :confirmation_token
  end
end