curl --request POST \
  --url https://api.opencard.io/api/v1/service/marcet/callback/{referenceId} \
  --header 'X-Data-Signature: <x-data-signature>' \
  --header 'X-Event: <x-event>'

const options = {
  method: 'POST',
  headers: {'X-Event': '<x-event>', 'X-Data-Signature': '<x-data-signature>'}
};

fetch('https://api.opencard.io/api/v1/service/marcet/callback/{referenceId}', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

import requests

url = "https://api.opencard.io/api/v1/service/marcet/callback/{referenceId}"

headers = {
    "X-Event": "<x-event>",
    "X-Data-Signature": "<x-data-signature>"
}

response = requests.post(url, headers=headers)

print(response.text)

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.opencard.io/api/v1/service/marcet/callback/{referenceId}",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_HTTPHEADER => [
    "X-Data-Signature: <x-data-signature>",
    "X-Event: <x-event>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}