Coinmarketcap PHP API 没有返回数据

只是通过 API 获取一些数据的简单测试不起作用。我使用了他们自己网站上的 PHP 示例，但没有打印结果。来源：https : //pro.coinmarketcap.com/api/v1#section/Quick-Start-Guide
我做错了什么吗？我使用带有演示 API 密钥的沙箱环境。Curl 安装在我的服务器上。非常感谢！

<?php
$url = 'https://sandbox-api.coinmarketcap.com/v1/cryptocurrency/listings/latest';
$parameters = [
  'start' => '1',
  'limit' => '5000',
  'convert' => 'USD'
];

$headers = [
  'Accepts: application/json',
  'X-CMC_PRO_API_KEY: b54bcf4d-1bca-4e8e-9a24-22ff2c3d462c'
];
$qs = http_build_query($parameters); // query string encode the parameters
$request = "{$url}?{$qs}"; // create the request URL


$curl = curl_init(); // Get cURL resource
// Set cURL options
curl_setopt_array($curl, array(
  CURLOPT_URL => $request,            // set the request URL
  CURLOPT_HTTPHEADER => $headers,     // set the headers 
  CURLOPT_RETURNTRANSFER => 1         // ask for raw response instead of bool
));

$response = curl_exec($curl); // Send the request, save the response
print_r(json_decode($response)); // print json decoded response
curl_close($curl); // Close request
?>

回答

error code: 1020

curl_setopt_array($curl, array(
CURLOPT_URL => $request,
CURLOPT_HTTPHEADER => $headers,
CURLOPT_RETURNTRANSFER => 1,
CURLOPT_USERAGENT => 'Mozilla/5.0 (Windows NT 6.2; WOW64; rv:17.0) Gecko/20100101 Firefox/17.0'
));

stdClass Object
(
[status] => stdClass Object
(
[timestamp] => 2021-08-30T15:06:20.200Z
[error_code] => 0
[error_message] =>
[elapsed] => 0
[credit_count] => 1
[notice] =>
)
[data] => Array
... and a lot more ...