Amazon S3 (Simple Storage Service) - Writing Data Objects to Buckets using PHP

< ?
   require_once 'Crypt/HMAC.php';
   require_once 'HTTP/Request.php';
 
   define ('DATE_RFC822',"D, d M Y G:i:s O");
   define ('S3_URL',"http://s3.amazonaws.com/");
   define ('KEYID',"Amazon KeyId");
   define ('SECRETKEY',"Amazon Secret Key");
   define ('PUT',"PUT");
   define ('CONTENT_TYPE',"File Mime Type");
   define ('PUBLIC_READ',"public-read");
 
   function putObject($bucketname,$key, $method = PUT,$acl = PUBLIC_READ,$filePath, $contentType = CONTENT_TYPE)
   {
     $contentLength = sprintf("%u", filesize($filePath));
     $resource = $bucketname."/".urlencode($key);
     $req =& new HTTP_Request(S3_URL.$resource);
     $req->setMethod($method);
     $httpDate = gmdate("D, d M Y G:i:s T");
     $req->addHeader("Date", $httpDate);
     $req->addHeader("Content-Type", $contentType);
     $req->addHeader("Content-Length", $contentLength);
     $req->addHeader("x-amz-acl", $acl);
 
     $MD5 = hex2b64(md5_file($filePath));
     $req->addHeader("Content-MD5", $MD5);
 
     $req->setBody(file_get_contents($filePath));
     $stringToSign="$methodn$MD5n$contentTypen$httpDatenx-amz-acl:$acln";
     $stringToSign.="/$resource";
     $hasher =& new Crypt_HMAC(SECRETKEY, "sha1");
     $signature = hex2b64($hasher->hash($stringToSign));
     $req->addHeader("Authorization", "AWS " . KEYID . ":" . $signature);
     $req->sendRequest();
     if ($req->getResponseCode() == 200)
     {
         echo "$filePath Object Uploaded Successfully";
     }
     else
     {
         echo "$filePath Object Not Uploaded Successfully";
     }
   }
putObject("bucket name","File Key Name",PUT,PUBLIC_READ,"Uploading File Path",CONTENT_TYPE);
?>