For generating a token on an active record column you can use tokenize

• column: the column of the active record
• options: some options for generating the token
  • :length: the token length (default: 8)
  • :uniq: whether the token must be uniq or not (default: true)
  • :scope: the column for the scope to check the uniqueness (default: nil)
  • :characters: an array of characters the tokens should be build from (default: a-zA-Z0-9)

  class User < ActiveRecord::Base
    tokenize :email_confirmation_token, length: 16
  end

this is equal to

  class User < ActiveRecord::Base
    before_validation on: :create do |obj|
      obj.generate_token :email_confirmation_token, length: 16
    end
  end

Currently the gem is not available on rubyforge, so you have to install it with git:

  gem 'ar-tokens'

This project rocks and uses MIT-LICENSE.