This example calculates request MAC according to "HTTP Authentication: MAC Access Authentication (draft 01)" example from webtopay wallet api (version 2)

gistfile1.txt

# author: Justas Janauskas, Marius Balčytis
# Aug 6, 2012
#
# This example calculates request MAC according to "HTTP Authentication: MAC Access Authentication (draft 01)"
# example from webtopay wallet api
#
# ref: http://tools.ietf.org/pdf/draft-ietf-oauth-v2-http-mac-01.pdf
# ref: https://www.webtopay.com/wallet/

require 'base64'
require 'openssl'

normalized_request_string = [
  '1343818800',
  'nQnNaSNyubfPErjRO55yaaEYo9YZfKHN',
  'GET',
  '/wallet/rest/v1/payment/10145',
  'www.webtopay.com',
  443,
  nil,
  nil
].join("\n")

puts normalized_request_string
hmac = OpenSSL::HMAC.digest(
  OpenSSL::Digest::SHA256.new,
  'IrdTc8uQodU7PRpLzzLTW6wqZAO6tAMU',
  normalized_request_string
)

mac = Base64.encode64(hmac).gsub(/\n/, '')

puts "I get \"#{mac}\", example has \"xTCR/i6LKbhXoo4Fe77ECowrn+Q6uUdX7yxwS/lhDWU=\""

# output:
# I get "xTCR/i6LKbhXoo4Fe77ECowrn+Q6uUdX7yxwS/lhDWU=", example has "xTCR/i6LKbhXoo4Fe77ECowrn+Q6uUdX7yxwS/lhDWU="