Ruby on Rails
Simple LDAP Authenticator

Allows for simple authentication to an LDAP server with a minimum of configuration. Requires either Ruby/LDAP or Net::LDAP.

Usage is fairly simple:

require 'simple_ldap_authenticator'
SimpleLdapAuthenticator.servers = %w'dc1.domain.com dc2.domain.com'
SimpleLdapAuthenticator.use_ssl = true
SimpleLdapAuthenticator.login_format = '%s @domain.com'
SimpleLdapAuthenticator.logger = RAILS_DEFAULT_LOGGER
class LoginController < ApplicationController
  def login
    return redirect_to(:action=>'try_again') unless SimpleLdapAuthenticator.valid?(params[:username], params[:password])  
    session[:username] = params[:username]
  end
end

github: http://github.com/jeremyevans/rails_plugins/tree/master
RDoc: http://code.jeremyevans.net/doc/simple_ldap_authenticator