Usando http digest authentication con Ruby

#! /usr/bin/ruby  
require 'digest/md5'  
require 'net/http'  

module Net  
module HTTPHeader  
@@nonce_count = -1  
CNONCE = Digest::MD5.new.update("%x" % (Time.now.to_i + rand(65535))).hexdigest  
def digest_auth(user, password, response)  
    # based on http://segment7.net/projects/ruby/snippets/digest_auth.rb  
    @@nonce_count += 1  
    response['www-authenticate'] =~ /^(\w+) (.*)/  
    params = {}  
    $2.gsub(/(\w+)="(.*?)"/) { params[$1] = $2 }  
    a_1 = "#{user}:#{params['realm']}:#{password}";  
    a_2 = "#{@method}:#{@path}";  
    request_digest = ''  
    request_digest << Digest::MD5.new.update(a_1).hexdigest  
    request_digest << ':' << params['nonce']  
    request_digest << ':' << ('%08x' % @@nonce_count)  
    request_digest << ':' << CNONCE  
    request_digest << ':' << params['qop']  
    request_digest << ':' << Digest::MD5.new.update(a_2).hexdigest  
    header = []  
    header << "Digest username=\"#{user}\""  
    header << "realm=\"#{params['realm']}\""  
    header << "qop=#{params['qop']}"  
    header << "algorithm=MD5"  
    header << "uri=\"#{@path}\""  
    header << "nonce=\"#{params['nonce']}\""  
    header << "nc=#{'%08x' % @@nonce_count}"  
    header << "cnonce=\"#{CNONCE}\""  
    header << "response=\"#{Digest::MD5.new.update(request_digest).hexdigest}\""  
    @header['Authorization'] = header  
end  
end  
end  

require 'net/http'  
Net::HTTP.start('server.name.com') {|http|  
    req = Net::HTTP::Get.new('/ticketless/mobi.php?id_bw=12345678')  
    response = http.request(req)  
    req.digest_auth 'mobi', 'bb41231ce581239061235cee1233d123', response  
    response = http.request(req)  
    print response.body  
}