Facebook Payment dialogue not working - facebook

Question

Here's the error code:
"The app you are using is not responding. Please try again later."
The callback is set to the php file (via https). I have no idea why it's not working.
Here's the JS (binded to var dr):
dr.buyCoins = function(){
var obj = {
method: 'pay',
order_info: order_info,
action: 'buy_item',
dev_purchase_params: {'oscif': true}
};
FB.ui(obj, dr.coinCheck);
}
dr.coinCheck = function(d){
if (d['order_id']) {
return true;
} else {
return false;
}
}
and here's the PHP:
<?php
$app_secret = '...';
// Validate request is from Facebook and parse contents for use.
$request = parse_signed_request($_POST['signed_request'], $app_secret);
// Get request type.
// Two types:
// 1. payments_get_items.
// 2. payments_status_update.
$request_type = $_POST['method'];
// Setup response.
$response = '';
if ($request_type == 'payments_get_items') {
// Get order info from Pay Dialog's order_info.
// Assumes order_info is a JSON encoded string.
$order_info = json_decode($request['credits']['order_info'], true);
// Get item id.
$item_id = $order_info['item_id'];
// Simulutates item lookup based on Pay Dialog's order_info.
if ($item_id == '1a') {
$item = array(
'title' => '100 some game cash',
'description' => 'Spend cash in some game.',
// Price must be denominated in credits.
'price' => 1,
'image_url' => 'http://some_image_url/coin.jpg',
);
// Construct response.
$response = array(
'content' => array(
0 => $item,
),
'method' => $request_type,
);
// Response must be JSON encoded.
$response = json_encode($response);
}
} else if ($request_type == "payments_status_update") {
// Get order details.
$order_details = json_decode($request['credits']['order_details'], true);
// Determine if this is an earned currency order.
$item_data = json_decode($order_details['items'][0]['data'], true);
$earned_currency_order = (isset($item_data['modified'])) ?
$item_data['modified'] : null;
// Get order status.
$current_order_status = $order_details['status'];
if ($current_order_status == 'placed') {
// Fulfill order based on $order_details unless...
if ($earned_currency_order) {
// Fulfill order based on the information below...
// URL to the application's currency webpage.
$product = $earned_currency_order['product'];
// Title of the application currency webpage.
$product_title = $earned_currency_order['product_title'];
// Amount of application currency to deposit.
$product_amount = $earned_currency_order['product_amount'];
// If the order is settled, the developer will receive this
// amount of credits as payment.
$credits_amount = $earned_currency_order['credits_amount'];
}
$next_order_status = 'settled';
// Construct response.
$response = array(
'content' => array(
'status' => $next_order_status,
'order_id' => $order_details['order_id'],
),
'method' => $request_type,
);
// Response must be JSON encoded.
$response = json_encode($response);
} else if ($current_order_status == 'disputed') {
// 1. Track disputed item orders.
// 2. Investigate user's dispute and resolve by settling or refunding the order.
// 3. Update the order status asychronously using Graph API.
} else if ($current_order_status == 'refunded') {
// Track refunded item orders initiated by Facebook. No need to respond.
} else {
// Track other order statuses.
}
}
// Send response.
echo $response;
// These methods are documented here:
// https://developers.facebook.com/docs/authentication/signed_request/
function parse_signed_request($signed_request, $secret) {
list($encoded_sig, $payload) = explode('.', $signed_request, 2);
// decode the data
$sig = base64_url_decode($encoded_sig);
$data = json_decode(base64_url_decode($payload), true);
if (strtoupper($data['algorithm']) !== 'HMAC-SHA256') {
error_log('Unknown algorithm. Expected HMAC-SHA256');
return null;
}
// check sig
$expected_sig = hash_hmac('sha256', $payload, $secret, $raw = true);
if ($sig !== $expected_sig) {
error_log('Bad Signed JSON signature!');
return null;
}
return $data;
}
function base64_url_decode($input) {
return base64_decode(strtr($input, '-_', '+/'));
}
?>

Answer 1

Check your server logs and make sure you're receiving the request and responding to it correctly - note that if your callback is HTTPS your certificate needs to be fully valid including all intermediate certificates
In your case sslchecker said you're possibly missing the intermediate chain - https://www.sslshopper.com/ssl-checker.html#hostname=https://drawabble.com