gistfile1.txt

/*
Return URL for validation and making pay requests

 array
  'signature' => string 'lyOR0dvgfv0nW36/LExYn58/J4FNZRqqkzXNwjezm80VTbTCjtRcbs0HNbTI/uhMTybjblnWn5Az
USaPYErzoazPP7CNAfjT4mKKzxRwUAukvRL70+tMyHiGwwM1O6mAW0/hM/RiTafSx8TzC5UIvKq1
1H07ndhTp0m/7qETZ4w=' (length=174)
  'expiry' => string '06/2016' (length=7)
  'signatureVersion' => string '2' (length=1)
  'signatureMethod' => string 'RSA-SHA1' (length=8)
  'certificateUrl' => string 'https://fps.sandbox.amazonaws.com/certs/090910/PKICert.pem?requestId=bjzj1gs373exlu22707fizn2s4amuxfop7uczyf3j7z4zdjdo38' (length=120)
  'tokenID' => string 'N12CGM7A6N8I9JEDNJJ77PUFTSPWXRI7LR7BM4J58KVNBQMU6BQKKX1UAJK4Y9HE' (length=64)
  'status' => string 'SC' (length=2)
  'callerReference' => string 'abc12345' (length=8)
*/

 $request = new Amazon_FPS_Model_PayRequest();
 
// $senderTokenID is obtained from the Co-Branded service's return URL
 $senderTokenId = "N12CGM7A6N8I9JEDNJJ77PUFTSPWXRI7LR7BM4J58KVNBQMU6BQKKX1UAJK4Y9HE";
 
 $request->setSenderTokenId($senderTokenId);
 
 $request->setCallerReference("hellogoodbye");
  
 $amount = new Amazon_FPS_Model_Amount();
 $amount->setCurrencyCode("USD");
 $amount->setValue('1'); 
 $request->setTransactionAmount($amount);
 
 $service = new Amazon_FPS_Client(AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY);
  
 invokePay($service, $request);