มีท่านใดเคยเขียน API ดึงสินค้าจาก Amazon บ้างครับ ขอแนวหน่อย

<?php

error_reporting(E_ALL);

//----Requester----------------------------------------------------------------------------------

define("ACCESS_KEY_ID","AKIAIYQTZRGPKBBTNG4Q"); 
define("SECRET_ACCESS_KEY","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");
define("ECS_VERSION","2009-10-01");
define("MAX_AMAZON_PAGE", 400);

function ItemSearch($browseNode='', $catetoryName='', $pageNumber='1', $keyword){
	if($browseNode == '') 
		return false;		
	$param = array( 
				"Operation"		=> "ItemSearch",
				"Condition"		=> "All", // or "New" or "Used" or "Collectible" or "Refurbished"
				"Keywords"		=> "$keyword",
				"SearchIndex"	=> "$catetoryName", //"Blended",Jewelry
				"Count"			=> "24",
				"BrowseNode"	=> "$browseNode",
				"ItemPage"		=> "$pageNumber",
				"Title"			=> "",
				"Sort"			=> "",
				"ResponseGroup"	=> "Small");

	$xml = get_xml_obj($param); 
	
	return $xml;
}
function get_xml_obj($param, $cacheperiod=900, $keyprefix='') { 
	ksort($param);
	if(! ($str=lookupAWS($param)) ) {
		echo 'lookupAWS returned false';
		return false;
	}
	$obj = simplexml_load_string($str);
	if(! $obj) {
		echo 'XML parse error';
		return false;
	}
	
	return $obj;
}
	
function lookupAWS($param) {
	$url = signedURL($param);
	if(!$url) return false;
	for($x=1; $x<3; $x++) {		
		$contents = @file_get_contents($url);
		if ($contents !== False)
			break;
		sleep(1);
	} 
	
	if($contents === False)
		return false;
		
	return $contents;
}
	
function signedURL($param) {
	if(!$param) 
		return '';
	$server = 'ecs.amazonaws.com';
	$uri = '/onca/xml'; 
	$method = 'GET';
	
	// additional parameters
	$param["Service"] = "AWSECommerceService";
	$param["AssociateTag"] = "itconner-20";
	$param["AWSAccessKeyId"] = rawurlencode(ACCESS_KEY_ID);
	$param["Timestamp"] = gmdate('Y-m-d\TH:i:s\Z');
	$param["Version"] = ECS_VERSION;
	
	ksort($param);
	
	$qa = array();
	foreach($param as $key=>$val) {
		$key = str_replace("%7E", "~", rawurlencode($key));
		$val = str_replace("%7E", "~", rawurlencode($val));
		$qa[$key] = rawurlencode($key) . '=' . $val;
	}
	
	$qs = implode('&',$qa); 
	$data = $method."\n".$server."\n".$uri."\n".$qs;
	$sig = base64_encode(hash_hmac('sha256', $data, SECRET_ACCESS_KEY, true));
	
	$sig = str_replace("%7E", "~", rawurlencode($sig));
	$url = "http://".$server.$uri."?".$qs."&Signature=".$sig;
	//echo $url;
	return $url;
}
//-------------------------------------------------------------------------------

function startJob(){
	$node = '672123011';
	$catetoryName = 'Shoes'; //example- Apparel, Beauty, Blended, Books
	$keyword = "";
	$page = 1;
	
	$xml = ItemSearch($node, $catetoryName, 1,$keyword);
	$totalpage = $xml->Items->TotalPages;	
	$browsenode = $xml->Items->Request->ItemSearchRequest->BrowseNode;
	if($totalpage > MAX_AMAZON_PAGE)
		$totalpage = MAX_AMAZON_PAGE;
	
	for($page=1;$page<=$totalpage;$page++){
			echo "<page: ".$page.">";
		foreach ($xml->Items->Item as $item) {			
				echo $item->ASIN."<br>";
		}		
		
		sleep(1);
		$xml = ItemSearch($node, $catetoryName, $page,$keyword);
	}
}

startJob();
?>