POSTing & quot; / orders & quot; к API GDAX не работает тихо

Я пытаюсь отправить «/ orders» в GDAX, используя простую функцию PHP. Я не получаю ответа и ошибок. Заказы не размещаются и нет ошибок / предупреждений PHP.

Не уверен, где я иду не так.

function gdaxPost ($path, $post_array){
$url = 'https://api-public.sandbox.gdax.com/'.$path;

// Sandbox API #1 - fake key
$key = "03cc35bd4fb48ardad8097e0a45f";
$secret = "ihGzWV+li8AweKcL+oMDUvBzlmq9fR7z6rKksg43VFcWA3zysg6TxM+gGhEn0wg==";
$passphrase = "jqer9jxgfa6qcl";

$time = time();
$data = $time."POST"."/orders";
$sign = base64_encode(hash_hmac("sha256", $data, base64_decode($secret), true));
$headers = array(
'CB-ACCESS-KEY: '.$key,
'CB-ACCESS-SIGN: '.$sign,
'CB-ACCESS-TIMESTAMP: '.$time,
'CB-ACCESS-PASSPHRASE: '.$passphrase,
'Content-Type: application/json'
);

$ch = curl_init();
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2228.0 Safari/537.36');
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($post_array));
curl_setopt($ch, CURLOPT_URL, $url);
$res = curl_exec($ch);
return $res;
}

$path = 'orders';
$post_array = array(
"price" => "600",
"size" => "1.01",
"side" => "buy",
"type" => 'limit',
"time_in_force" => "GTC",
"product_id" => "BTC-USD");

print_r(json_decode(gdaxPost ($path, $post_array)),true);

РЕДАКТИРОВАТЬ: я исправил код!

Это обновленный рабочий код:

function gdaxPost ($path, $post_array){
$url = 'https://api-public.sandbox.gdax.com/'.$path;

// Sandbox API #1 - fake key
$key = "03cc35bd4fb48ardad8097e0a45f";
$secret = "ihGzWV+li8AweKcL+oMDUvBzlmq9fR7z6rKksg43VFcWA3zysg6TxM+gGhEn0wg==";
$passphrase = "jqer9jxgfa6qcl";

$time = time();
$data = $time."POST"."/".$path.json_encode($post_array);
$sign = base64_encode(hash_hmac("sha256", $data, base64_decode($secret), true));
$headers = array(
'CB-ACCESS-KEY: '.$key,
'CB-ACCESS-SIGN: '.$sign,
'CB-ACCESS-TIMESTAMP: '.$time,
'CB-ACCESS-PASSPHRASE: '.$passphrase,
'Content-Type: application/json'
);

$ch = curl_init();
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2228.0 Safari/537.36');
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($post_array));
curl_setopt($ch, CURLOPT_URL, $url);
$res = curl_exec($ch);
return $res;
}

$path = 'orders';
$post_array = array(
"price" => "600",
"size" => "1.01",
"side" => "buy",
"type" => 'limit',
"time_in_force" => "GTC",
"product_id" => "BTC-USD");

print_r(gdaxPost ($path, $post_array));