In App Purchase テスト用スクリプト Receiptファイルは適宜どっかから持って来て receipt と言うファイル名で同一ディレクトリに置いて下さい

velify_receipt.rb

require 'rest_client'
require 'json'

params_json = "{ \"receipt-data\": \"#{open("./receipt").read}\"  }"

apple_url = "https://buy.itunes.apple.com/verifyReceipt"
receipt_data =  "#{open("./receipt").read}"
#p receipt_data
res = RestClient.post apple_url, {:'receipt-data' => receipt_data}.to_json
res = JSON.parse(res)
if res["status"] == 21007
  apple_url = "https://sandbox.itunes.apple.com/verifyReceipt"
  res = RestClient.post apple_url, {:'receipt-data' => receipt_data}.to_json
  res = JSON.parse(res)
  p "SANDBOX RECEIPT RESPONSE #{res}"
else
  p "PRODUCTION RECEIPT or FAILURE RESPONSE #{res}"
end

参考と謝辞

http://blog.designrecipe.jp/2009/9/6/ruby-rest-client/

https://gist.github.com/sauloarruda/2559455