First, I need help about login_generator, I am a programmer of rails applications. I have some examples for this ruby gem.

I share this with us.

1.- First It's necessary to install login_generator gem

<file>sudo gem install login_generator</file>

2.- you need to create a model 

<file>./script/generate model user</file>

this command create a file called user.rb that contains this:

<code ruby>
#-----------------------user.rb in  a models folder ----------------------
require 'digest/sha1'

# this model expects a certain database layout and its based on the name/login pattern.
class User < ActiveRecord::Base

  def self.authenticate(login, pass)
    find_first(["login = ? AND password = ?", login, sha1(pass)])
  end

  def change_password(pass)
    update_attribute "password", self.class.sha1(pass)
  end

  protected

  def self.sha1(pass)
    Digest::SHA1.hexdigest("change-me--#{pass}--")
  end

  before_create :crypt_password

  def crypt_password
    write_attribute("password", self.class.sha1(password))
  end

  validates_length_of :login, :within => 3..40
  validates_length_of :password, :within => 5..40
  validates_presence_of :login, :password, :password_confirmation
  validates_uniqueness_of :login, :on => :create
  validates_confirmation_of :password, :on => :create
end
</code>

3.- then, rails by default create a migration file that should have the follow:

<code ruby>
class CreateUsers < ActiveRecord::Migration
  def self.up
  create_table :users do |t|
  t.column :login, :string, :default => nil
  t.column :password, :string, :default => nil
  end

    User.create(:login => 'administrador',
  :password => 'password',
  :password_confirmation => 'password')

  end

  def self.down
  drop_table :users
  end
end
</code>

4.- It's necesarry have a file login_system.rb in a lib folder of your rails project, the most easy way to apply login_generator system it's to eject the command

<file>
./script/generate login_generator <name of controller>
</file>

5.- comments with Carlos Augusto Monterrosa Lopez
    http://cmonterrosatechnotes.blogspot.com