About the library

• Based on the 2008-09-17 API version.
• Version 1.0.1

Before you begin

Extract the contents of amazon-fps-2008-09-17-php5-library.zip to a folder. The folder "amazon-fps-2008-09-17-php5-library" will be created. This folder will be referred to as <ROOT> from this point onwards. This folder should contain the following sub-directories:

• src — This folder contains the code files for the library and sample API calls to Amazon FPS.

Prerequisites

Configuration

1. Update the keys required to make the API call. This is one time activity and should be same for all APIs
• Goto <ROOT>/src/Amazon/FPS/Samples directory
• Open the .config.inc.php file
• Change the following two lines and save the file
1. define('AWS_ACCESS_KEY_ID', '');
2. define('AWS_SECRET_ACCESS_KEY', '');
2. Update the FPS endpoint (only required for sandbox environment, for prodouction no changes are required)
• Open the CBUIUtils.php file
• Change the following line if needed and save the file
1. private static $cbui_url = "https://authorize.payments-sandbox.amazon.com";
• Open the Client.php file
• Change the following line if needed and save the file
1. private $_config = array ('ServiceURL' ='https://fps.sandbox.amazonaws.com')

Steps to make a payment

Description : Making a payment involves two parts. First, you obtain a payment authorization from buyers by redirecting them to co-branded pages hosted by Amazon FPS. When buyers return to your web site, you receive a payment authorization(also called a sender token) as part of the return URL. Second, you use this payment authorization or sender token in a 'Pay' API call to make a payment.

1. Setup an app server at your side to receive HTTP redirect from Cobranded UI.
2. Get the authorization from the buyer
• Go to Samples directory and open CBUISample.php
• In function getURLForSingleUseToken, set the corresponding fields

$obj = new Amazon_FPS_CBUIUtils(AWS_ACCESS_KEY_ID,AWS_SECRET_ACCESS_KEY);
$obj->setMandatoryParams("SingleUse", "<Your Return URL>");
$obj->setCallerReference("<some unique id to identify the request>");
$obj->setTransactionAmount("<transaction amount>");
$obj->setPaymentReason("<payment reason>");
$qs = $obj->getURL();
....
//getURLForSingleUseToken();
          

• Uncomment the function call to getURLForSingleUseToken and run php CBUISample.php
• Copy the URL printed on console and paste it on your browser. You will be redirected to Amazon FPS CBUI
• Go through the pipeline. Make sure you use a different Amazon FPS account, while acting as buyer. At the end of the pipeline, you(buyer) will be redirected back to the return URL provided in the query string above.
• The return URL will include expiry, tokenID, status, callerReference and signature parameters. Please note that tokenID will be used in Pay later.
• Validate that Amazon FPS actually returned the URL
1. Go to Samples directory and open CBUISample.php
2. In function validateQueryString, set the corresponding fields

echo "validing the query string now\n";
$querystring = "< query string returned by CBUI >";
$obj = new Amazon_FPS_CBUIUtils(AWS_ACCESS_KEY_ID,AWS_SECRET_ACCESS_KEY);
//Original signature received in response from Amazon FPS should be specified.
$signatureMatched=$obj->validateQueryString($querystring,urldecode("<signature parameter returned in the query string>"));                
...
//validateQueryString();
            

3. Uncomment the function call to validateQueryString and run php CBUISample.php
4. Make sure the signature is valid
3. Now we need to make the payment
• Open PaySample.php in <ROOT>/src/Amazon/FPS/Samples
• Set SenderTokenId the same as the one returned by CBUI above
• Replace the following line

   // @TODO: set request. Action can be passed as Amazon_FPS_Model_PayRequest

  with the code snippet below:

  $request =  new Amazon_FPS_Model_PayRequest();
  $request->setSenderTokenId('A12345666666BCDEFFF');//set the proper senderToken here.
  $amount = new Amazon_FPS_Model_Amount();
  $amount->setCurrencyCode("USD");
  $amount->setValue('1'); //set the transaction amount here;
  $request->setTransactionAmount($amount);
  $request->setCallerReference('CallerReference123456789'); //set the unique caller reference here.
                  

• Run php PaySample.php to make the pay API call
4. If the response status is Pending, you can use GetTransactionStatus API to get latest transaction status

Congratulations!! You made first call go through

Trouble shooting

1. The signature received in response doesn't match.
• Make sure you pass the URL decoded signature to Amazon_FPS_CBUIUtils->validateQueryString() method.
2. Fatal error: require_once(): Failed opening required 'Crypt/HMAC.php'
• Download Crypt/HMAC from here
• Include it in your package.

Related resources