Quick-and-dirty LDAP/local fallback auth for hudson

hudson_custom_auth.rb

#!/usr/bin/env ruby

require "rubygems"
require "net/ldap"
require "csv"

unless ARGV[0] && ARGV[1]
  puts "Usage: #{__FILE__} <username> <password>"
  abort
end

user = ARGV[0]
pass = ARGV[1]

# check local accounts setup in accounts.csv first
# useful for local or non-person accounts like git/hg in a post commit trigger
CSV.open(File.join(File.dirname(__FILE__), 'accounts.csv'), 'r') do |a|
  if user == a[0] && pass == a[1]
    puts "User #{user} authenticated successfully"
    exit
  end
end

# if no local accounts were successful, then fallback to ldap, sql, pam, etc.
# here's an ldap example
ldap = Net::LDAP.new :host => "ldap.example.com", :port => 389,
  :auth => {
    :method => :simple,
    :username => "cn=#{user},ou=staff,o=example",
    :password => pass
  }

if ldap.bind
  puts "User #{user} authenticated successfully"
  exit
else
  puts "User #{user} failed to authenticate"
  abort
end

This sounds interesting. But could you please elaborate on how to install this script in Hudson? I have no clue.