how to implement paypal in cakephp?

Here is an idea how to implement paypal in cakephp less than 5 mins? Answer is use Socket programming!! Yes, I found these very handy two classes from my friend Rajib Deb. So big big thanks for him.

Now step by step to implementation of this component.

Step 1: Create paypal.php file in /app/controllers/components/
Step 2: Paste this two class in paypal.php file

class HTTPRequest {

private $host;
private $path;
private $method;
private $port;
private $rawhost;

private $header;
private $content;
private $parsedHeader;

function __construct($host, $path, $method = 'POST', $ssl = false, $port = 0) {
$this->host = $host;
$this->rawhost = $ssl ? ("ssl://".$host) : $host;
$this->path = $path;
$this->method = strtoupper($method);
if ($port) {
$this->port = $port;
} else {
if (!$ssl) $this->port = 80; else $this->port = 443;
}
}

public function connect( $data = ''){
$fp = fsockopen($this->rawhost, $this->port);
if (!$fp) return false;
fputs($fp, "$this->method $this->path HTTP/1.1\r\n");
fputs($fp, "Host: $this->host\r\n");
//fputs($fp, "Content-type: $contenttype\r\n");
fputs($fp, "Content-length: ".strlen($data)."\r\n");
fputs($fp, "Connection: close\r\n");
fputs($fp, "\r\n");
fputs($fp, $data);

$responseHeader = '';
$responseContent = '';

do
{
$responseHeader.= fread($fp, 1);
}
while (!preg_match('/\\r\\n\\r\\n$/', $responseHeader));


if (!strstr($responseHeader, "Transfer-Encoding: chunked"))
{
while (!feof($fp))
{
$responseContent.= fgets($fp, 128);
}
}
else
{

while ($chunk_length = hexdec(fgets($fp)))
{
$responseContentChunk = '';

$read_length = 0;

while ($read_length < $chunk_length)
{
$responseContentChunk .= fread($fp, $chunk_length - $read_length);
$read_length = strlen($responseContentChunk);
}

$responseContent.= $responseContentChunk;

fgets($fp);

}

}

$this->header = chop($responseHeader);
$this->content = $responseContent;
$this->parsedHeader = $this->headerParse();

$code = intval(trim(substr($this->parsedHeader[0], 9)));

return $code;
}

function headerParse(){
$h = $this->header;
$a=explode("\r\n", $h);
$out = array();
foreach ($a as $v){
$k = strpos($v, ':');
if ($k) {
$key = trim(substr($v,0,$k));
$value = trim(substr($v,$k+1));
if (!$key) continue;
$out[$key] = $value;
} else
{
if ($v) $out[] = $v;
}
}
return $out;
}

public function getContent() {return $this->content;}
public function getHeader() {return $this->parsedHeader;}


}


class PaypalComponent extends Object {

var $endpoint;
var $host;
var $gate;
var $returnSuccessUrl;
var $returnCancelUrl;
var $paypalUserName;
var $paypalPassword;
var $paypalSignature;

function __construct($real = false) {
$this->endpoint = '/nvp';
if ($real) {
/*
* Production Credentials
*/
$this->host = "api-3t.paypal.com";
$this->gate = 'https://www.paypal.com/cgi-bin/webscr?';
} else {
/*
* Sendbox Credentials for testing purpose
*/
$this->host = "api-3t.sandbox.paypal.com";
$this->gate = 'https://www.sandbox.paypal.com/cgi-bin/webscr?';
}
}

/**
* @return string URL of the "success" page
*/
function getReturnTo() {
return $this->returnSuccessUrl;
}

/**
* @return string URL of the "cancel" page
*/
function getReturnToCancel() {
return $this->returnCancelUrl;
}

/**
* @return HTTPRequest
*/
function response($data){
$r = new HTTPRequest($this->host, $this->endpoint, 'POST', true);
$result = $r->connect($data);
if ($result->paypalUserName)
$data['PWD'] = $this->paypalPassword;
$data['SIGNATURE'] = $this->paypalSignature;
$data['VERSION'] = '51.0';
if(!function_exists('http_build_query')) {
$query = $this->http_build_query_php4($data);
} else {
$query = http_build_query($data);
}
return $query;
}
function http_build_query_php4($data,$b='',$c=0){
if (!is_array($data)) return false;
foreach ((array)$data as $key=>$value){
$pair[]=$key."=".urlencode($value);
}
return implode("&amp;",$pair);
}

/**
* Main payment function
*
* If OK, the customer is redirected to PayPal gateway
* If error, the error info is returned
*
* @param float $amount Amount (2 numbers after decimal point)
* @param string $desc Item description
* @param string $invoice Invoice number (can be omitted)
* @param string $currency 3-letter currency code (USD, GBP, CZK etc.)
*
* @return array error info
*/
function doExpressCheckout($amount, $desc, $invoice='', $currency='USD'){
$data = array(
'PAYMENTACTION' =>'Sale',
'AMT' =>$amount,
'RETURNURL' =>$this->getReturnTo(),
'CANCELURL'  =>$this->getReturnToCancel(),
'DESC'=>$desc,
'NOSHIPPING'=>"1",
'ALLOWNOTE'=>"1",
'CURRENCYCODE'=>$currency,
'METHOD' =>'SetExpressCheckout');

$data['CUSTOM'] = $amount.'|'.$currency.'|'.$invoice;
if ($invoice) $data['INVNUM'] = $invoice;

$query = $this->buildQuery($data);

$result = $this->response($query);

if (!$result) return false;
$response = $result->getContent();
$return = $this->responseParse($response);
if ($return['ACK'] == 'Success') {
header('Location: '.$this->gate.'cmd=_express-checkout&amp;useraction=commit&amp;token='.$return['TOKEN'].'');
die();
}
return($return);
}

function getCheckoutDetails($token){
$data = array(
'TOKEN' => $token,
'METHOD' =>'GetExpressCheckoutDetails');
$query = $this->buildQuery($data);

$result = $this->response($query);

if (!$result) return false;
$response = $result->getContent();
$return = $this->responseParse($response);
return($return);
}
function doPayment(){
$token = $_GET['token'];
$payer = $_GET['PayerID'];
$details = $this->getCheckoutDetails($token);
if (!$details) return false;
list($amount,$currency,$invoice) = explode('|',$details['CUSTOM']);
$data = array(
'PAYMENTACTION' => 'Sale',
'PAYERID' => $payer,
'TOKEN' =>$token,
'AMT' => $amount,
'CURRENCYCODE'=>$currency,
'METHOD' =>'DoExpressCheckoutPayment');
$query = $this->buildQuery($data);

$result = $this->response($query);

if (!$result) return false;
$response = $result->getContent();
$return = $this->responseParse($response);

/*
* [AMT] => 10.00
* [CURRENCYCODE] => USD
* [PAYMENTSTATUS] => Completed
* [PENDINGREASON] => None
* [REASONCODE] => None
*/

return($return);
}

function getScheme() {
$scheme = 'http';
if (isset($_SERVER['HTTPS']) and $_SERVER['HTTPS'] == 'on') {
$scheme .= 's';
}
return $scheme;
}

function responseParse($resp){
$a=explode("&amp;", $resp);
$out = array();
foreach ($a as $v){
$k = strpos($v, '=');
if ($k) {
$key = trim(substr($v,0,$k));
$value = trim(substr($v,$k+1));
if (!$key) continue;
$out[$key] = urldecode($value);
} else {
$out[] = $v;
}
}
return $out;
}

function doDirectPayment($Order) {

$Order['METHOD'] = 'DoDirectPayment';

$query = $this->buildQuery($Order);

$result = $this->response($query);
if (!$result)
return false;
$response = $result->getContent();
return $this->responseParse($response);

}
}

Step 3: In your controller add

var $components=array( ‘Paypal’);

Step 4: For PayPal Express Check Out use somthing like

public function expressPaypalCheckOut(){
$this->Paypal->paypalUserName = $pyapal_settings['user'];
$this->Paypal->paypalPassword = $pyapal_settings['password'];
$this->Paypal->paypalSignature = $pyapal_settings['signature'];
$this->Paypal->returnSuccessUrl = "/success/url/returnByPaypal/pay?csid=" . session_id();
$this->Paypal->returnCancelUrl = "/cancel/url/returnByPaypal/cancel?csid=".session_id();
$ret = ($this->Paypal->doExpressCheckout($user_info["amount"], 'Access to source code library','','EUR')); // use USD for dollar
}

Step 5: For PayPal Direct Payment use somthing like

$order = array(
'PAYMENTACTION'=>'Sale',
'AMT'=> ($FREQUEST->postvalue('amount')/100),
'CREDITCARDTYPE'=>$FREQUEST->postvalue('card_type'),
'ACCT'=>$FREQUEST->postvalue('creditCard1'),
'EXPDATE'=>$FREQUEST->postvalue('expire_month').$FREQUEST->postvalue('expire_year'),
'CVV2'=>$FREQUEST->postvalue('cvvno'),
'FIRSTNAME'=> $session_information["billto_array"]["firstname"],
'LASTNAME'=> $session_information["billto_array"]["lastname"],
'STREET'=> $session_information["billto_array"]["street_address"],
'CITY'=>$session_information["billto_array"]["city"],
'STATE'=> $session_information["billto_array"]["state"],
'ZIP'=> $session_information["billto_array"]["postcode"],
'COUNTRYCODE'=> $session_information["billto_array"]["country"]["iso_code_2"],
'CURRENCYCODE'=> 'USD'</code>

);

$this->Paypal->paypalUserName = $pyapal_settings['user'];
$this->Paypal->paypalPassword = $pyapal_settings['password'];
$this->Paypal->paypalSignature = $pyapal_settings['signature'];
$this->Paypal->returnSuccessUrl = "/success/url/returnByPaypal/pay?csid=" . session_id();
$this->Paypal->returnCancelUrl = "/cancel/url/returnByPaypal/cancel?csid=".session_id();
$ret = ($this->Paypal->doDirectPayment($order));
</blockquote>

<strong>6</strong> Now after getting the responds from PayPal you need to reconfigure again the PayPal settings something like
<blockquote>
public function returnByPaypal($callback = null){
if ($callback == 'cancel') {
			$this->redirect("your/cancel/page");
	        exit;
	    } else if ($callback == 'pay') {
               $pyapal_settings = Configure::read('paypal_settings');
			$this->Paypal->paypalUserName = $pyapal_settings['user'];
			$this->Paypal->paypalPassword = $pyapal_settings['password'];
			$this->Paypal->paypalSignature = $pyapal_settings['signature'];
			$paypalRespons = $this->Paypal->doPayment();
                        if($paypalRespons['ACK'] == 'Success'){
                             /* your code in here*/
                        }
            }
}

Well, thats it. Please consider some syntax error or other cause i am not testing these code yet!!! enjoy

Inspired from Martin Maly’s Paypal Library