AlexaSiteThumbnail Web Services

<?php

class alexa extends webservices {

	public function thumbnail() {

		$query  = $this->parameters['url']; // full url

		$domain = 'http://' . parse_url($query,PHP_URL_HOST) . '/'; // just the main domain page

		$urls   = array($query,$domain);

		

		$access_key_id = $this->setting_variable('apikey.amazon.access_key_id');

		$private_key   = $this->setting_variable('apikey.amazon.secret_access_key');

		

        $timestamp     = gmdate("Y-m-d\TH:i:s.\\0\\0\\0\\Z", time());

        $timestamp_enc = urlencode($timestamp);

        $signature_enc = urlencode ( $this->calculate_RFC2104HMAC("AlexaSiteThumbnail" . "Thumbnail" . $timestamp, $private_key));

        $size          = "Small";

        

        $urls_param    = "";

        for ($i = 0; $i < count($urls); $i++) $urls_param .= "&Thumbnail." . ($i+1) . ".Url=" . urlencode($urls[$i]);

        

        $request_url =  "http://ast.amazonaws.com/xino/?"

        	. "Service=".         "AlexaSiteThumbnail"

			. "&Action=".         "Thumbnail"

			. "&AWSAccessKeyId=". $access_key_id

			. "&Timestamp=" .     $timestamp_enc

			. "&Signature=" .     $signature_enc

			. "&Shared.Size=" .   $size

			. $urls_param;

                        

        $result = $this->get($request_url);

        

        $response_doc = new DOMDocument();

        $response_doc->loadXML($result);

        $responses = $response_doc->getElementsByTagName("Response");

        

        $results = array();

        

        // full query

        $thumbnail = $responses->item(0)->getElementsByTagName("Thumbnail")->item(0);

        $results['full'] = array(

        	'thumbnail' => $thumbnail->firstChild->nodeValue

        	, 'found' => ($thumbnail->getAttribute("Exists") == "true") ? true : false

        );


        // domain query

        $thumbnail = $responses->item(1)->getElementsByTagName("Thumbnail")->item(0);

        $results['domain'] = array(

        	'thumbnail' => $thumbnail->firstChild->nodeValue

        	, 'found' => ($thumbnail->getAttribute("Exists") == "true") ? true : false

        );

        

        return $results;

	}

	

	private function calculate_RFC2104HMAC($data,$key) {

	    return base64_encode (

        pack("H*", sha1((str_pad($key, 64, chr(0x00))

        ^(str_repeat(chr(0x5c), 64))) .

        pack("H*", sha1((str_pad($key, 64, chr(0x00))

        ^(str_repeat(chr(0x36), 64))) . $data))))

     );

	}

	

}

?>