PayPal PHP SDK - payment creation doesn't work on production - empty response

Question

I'm just facing that problem for hours. This complete app works locally (OSX/MAMP/modphp/PHP 5.5.18) but for some reason on the production server the payment creation fails: White/Empty response. No Exception, no max_execution time limit reached also HTTP 200. PHP and Apache logs are just fine and also there are no errors on the screen.

Everything before $payment->create($this->apiContext); gets executed - after that line the result is blank page.

The production server runs Ubuntu 14.04 / Apache 2.4.7 / modphp / PHP 5.5.9

Here is the code:

public function create($data)
{
    $payer = new Payer();
    $payer->setPaymentMethod("paypal");

    $total    = 0.0;
    $shipping = 0.0;
    foreach ($data as $key => $value) {
        $item = new Item();
        $item->setName($value->name)
            ->setDescription($value->type)
            ->setCurrency(Option::get('general-settings', 'currency'))
            ->setQuantity($value->amount)
            ->setPrice($value->price);

        $items[] = $item;
        $total += $value->price * $value->amount;
    }

    if ($total < 100) {
        $shipping += 10;
    }

    $itemList = new ItemList();
    $itemList->setItems($items);

    $details = new Details();
    $details->setShipping($shipping)
    ->setSubtotal($total);

    $amount = new Amount();
    $amount->setCurrency(Option::get('general-settings', 'currency'))
        ->setTotal($total+$shipping)
        ->setDetails($details);

    $transaction = new Transaction();
    $transaction->setAmount($amount)
        ->setItemList($itemList)
        ->setDescription("JustinRein Auftag")
        ->setInvoiceNumber(uniqid());

    $baseUrl = "http://example.ch";
    $redirectUrls = new RedirectUrls();
    $redirectUrls->setReturnUrl("$baseUrl/payment?success=true")
        ->setCancelUrl("$baseUrl/payment?success=false");

    $payment = new Payment();
    $payment->setIntent("sale")
        ->setPayer($payer)
        ->setRedirectUrls($redirectUrls)
        ->setTransactions(array($transaction));

    try {
        $payment->create($this->apiContext);

    } catch (Exception $ex) {
        td($ex);
        exit(1);
    }

    return $payment;
}

This runs also on paypal sandbox mode. The paypal logfile is also empty.

Answer 1

Posting here to close out the question. Question author investigated and found a third party library that he was using which was suppressing the error that he needed to see with a '@' operator. After removing the '@' operator (temporarily?) he was able to correct the problem with the PayPal SDK that he was using.