I work on a website based on Symfony 3 and PayPal API. 

I tried to use IPN outside Symfony and it worked well. 

Now I try to implements this into my controller and nothing happens.

This code comes from the Paypal's Github. 

```
public function paypalAction(Request $request){
  // STEP 1: Read POST data

  // reading posted data from directly from $_POST causes serialization
  // issues with array data in POST
  // reading raw POST data from input stream instead.
  $raw_post_data = $request->getContent();
  $raw_post_array = explode('&', $raw_post_data);
  $myPost = array();
  foreach ($raw_post_array as $keyval) {
    $keyval = explode ('=', $keyval);
    if (count($keyval) == 2)
       $myPost[$keyval[0]] = urldecode($keyval[1]);
  }
  // read the post from PayPal system and add 'cmd'
  $req = 'cmd=_notify-validate';
  if(function_exists('get_magic_quotes_gpc')) {
     $get_magic_quotes_exists = true;
  }
  foreach ($myPost as $key => $value) {
     if($get_magic_quotes_exists == true && get_magic_quotes_gpc() == 1) {
          $value = urlencode(stripslashes($value));
     } else {
          $value = urlencode($value);
     }
     $req .= "&$key=$value";
  }

  // STEP 2: Post IPN data back to paypal to validate

  $ch = curl_init('https://www.sandbox.paypal.com/cgi-bin/webscr');
  curl_setopt($ch, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);
  curl_setopt($ch, CURLOPT_POST, 1);
  curl_setopt($ch, CURLOPT_RETURNTRANSFER,1);
  curl_setopt($ch, CURLOPT_POSTFIELDS, $req);
  curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 1);
  curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
  curl_setopt($ch, CURLOPT_FORBID_REUSE, 1);
  curl_setopt($ch, CURLOPT_HTTPHEADER, array('Connection: Close'));

  // In wamp like environments that do not come bundled with root authority certificates,
  // please download 'cacert.pem' from "http://curl.haxx.se/docs/caextract.html" and set the directory path
  // of the certificate as shown below.
  // curl_setopt($ch, CURLOPT_CAINFO, dirname(__FILE__) . '/cacert.pem');
  if( !($res = curl_exec($ch)) ) {
      // error_log("Got " . curl_error($ch) . " when processing IPN data");
      curl_close($ch);
      exit;
  }
  curl_close($ch);

  // STEP 3: Inspect IPN validation result and act accordingly

  if (strcmp ($res, "VERIFIED") == 0) {
      // check whether the payment_status is Completed
      // check that txn_id has not been previously processed
      // check that receiver_email is your Primary PayPal email
      // check that payment_amount/payment_currency are correct
      // process payment

      // assign posted variables to local variables

      $item_name = $_POST['item_name'];
      $item_number = $_POST['item_number'];
      $cart_item = $_POST['num_cart_items'];
      $payment_status = $_POST['payment_status'];
      $payment_amount = $_POST['mc_gross'];
      $payment_currency = $_POST['mc_currency'];
      $txn_id = $_POST['txn_id'];
      $receiver_email = $_POST['receiver_email'];
      $payer_email = $_POST['payer_email'];

      // <---- HERE you can do your INSERT to the database
      return new Response("Paypal worked !");
  } else if (strcmp ($res, "INVALID") == 0) {
      // log for manual investigation
      return new Response("Paypal didn't worked !");
  }
}

```