Facebook credits回调检测请求

Question

有没有办法检测回调请求是否来自facebook，因为该请求似乎不是ajax。

Answer 1

来自：http://developers.facebook.com/docs/credits/callback/

您可以通过解码signed_request来验证回调是否被Facebook调用。

{
   "signed_request":"PfjakldsFWWs...",
   "buyer":"221159",
   "receiver":"221159",
   "order_id":"9006136047935",
   "order_info":""fbhat"",
   "method":"payments_get_items"
}