curl --request POST \
  --url https://api.opencard.io/oauth/token \
  --header 'Content-Type: application/json' \
  --data '
{
  "grant_type": "client_credentials",
  "client_id": "your-client-id",
  "client_secret": "your-secret",
  "scope": "organizations-write webhooks-write card-holders-write"
}
'

const options = {
  method: 'POST',
  headers: {'Content-Type': 'application/json'},
  body: JSON.stringify({
    grant_type: 'client_credentials',
    client_id: 'your-client-id',
    client_secret: 'your-secret',
    scope: 'organizations-write webhooks-write card-holders-write'
  })
};

fetch('https://api.opencard.io/oauth/token', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

import requests

url = "https://api.opencard.io/oauth/token"

payload = {
    "grant_type": "client_credentials",
    "client_id": "your-client-id",
    "client_secret": "your-secret",
    "scope": "organizations-write webhooks-write card-holders-write"
}
headers = {"Content-Type": "application/json"}

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

print(response.text)

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.opencard.io/oauth/token",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'grant_type' => 'client_credentials',
    'client_id' => 'your-client-id',
    'client_secret' => 'your-secret',
    'scope' => 'organizations-write webhooks-write card-holders-write'
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json"
  ],
]);

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

curl_close($curl);

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

{
  "token_type": "Bearer",
  "expires_in": 31536000,
  "access_token": "eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiJ9..."
}