HasDigest¶ ↑

HasDigest is an ActiveRecord macro that makes it easy to write things like encrypted passwords and api tokens before_save. Digest attributes may either stand alone or depend on the values of other attributes. Digests with dependencies are also magically salted for models having a salt attribute.

See the documentation for the has_digest method for options.

Installation¶ ↑

As a gem:

config.gem 'matthewtodd-has_digest', :lib => 'has_digest', :source => 'http://gems.github.com'

As a plugin:

script/plugin install git://github.com/matthewtodd/has_digest.git

Usage¶ ↑

In your model:

class User < ActiveRecord::Base
  has_digest :encrypted_password, :depends => :password
end

In your migrations:

class CreateUsers < ActiveRecord::Migration
  def self.up
    create_table :users do |t|
      t.string :salt, :encrypted_password, :limit => 40
    end
  end

  def self.down
    drop_table :users
  end
end

In your tests:

class UserTest < ActiveSupport::TestCase
  should_have_digest :encrypted_password, :depends => :password
end

Back in your model:

class User < ActiveRecord::Base
  def authenticate(password)
    encrypted_password == digest(salt, password)
  end
end

Copyright © 2008 Matthew Todd, released under the MIT license