Using zend_service_amazon, but not seeing any output

Question

I'm playing around with the Amazon developer's API and I'm not getting anything.

Here is my code. I am using echo to see if anything is happening and all I am getting is a blank webpage. I expected the array of search results to be echoed.

<?php
error_reporting(E_ALL); 
ini_set("display_errors", 1); 
require_once('Zend/Service/Amazon.php');

$amazon = new Zend_Service_Amazon('AKIAJQBYUXIFWUIX6W6A', 'US', 'YGV9zePfKejV6C3dpaP/NtnhjGLfWQsccdGSSL50');
$results = $amazon->itemSearch(array('SearchIndex' => 'Books',
                                     'Keywords' => 'php'));
foreach ($results as $result) {
    echo $result->Title . '<br />';
}

    ?>

getting a blank page still

Answer 1

Your page is blank because you are no getting any results:

This is the $results dump using your published code:

Amazon object(Zend_Service_Amazon_ResultSet)#103 (4) {
  ["_results":protected] => object(DOMNodeList)#105 (0) {
  }
  ["_dom":protected] => object(DOMDocument)#101 (0) {
  }
  ["_xpath":protected] => object(DOMXPath)#104 (0) {
  }
  ["_currentIndex":protected] => int(0)
}

There are several issues to resolve to make this work, the biggest one being this:

The following changes will take effect on 11/1/2011:
Associate Tag Parameter: Every request made to the API should include a valid Associate Tag. Any request that does not contain a valid Associate Tag will be rejected with an appropriate error message. For details on the Associate Tag parameter, please refer to our Developer guide.

Currently the constructor for Zend_Service_Amazon does not include the Associate Tag parameter and the _prepareOptions() method does not set the option.

I'm sure someone has a fix for this, otherwise it's time to dig in and extend... Good Luck

Amazon Product Advertising API
Changes to Product Advertising API