allpay_api_sample.php

<?php
civicrm_initialize();
$pid = 1; // payment processor id from system
$payment_processor = CRM_Core_BAO_PaymentProcessor::getPayment($pid, 'live');
$contribution_trxn_id = 'ABCDE12345';

if($payment_processor['payment_processor_type'] == 'ALLPAY' || $payment_processor['payment_processor_type'] == 'ALLPAYX'){
  if(!empty($payment_processor['url_recur']) && !empty($payment_processor['user_name'])){
    $processor = array(
      'password' => $payment_processor['password']
      'signature' => $payment_processor['signature'],
    );
    $post_data = array(
      'MerchantID' => $payment_processor['user_name'],
      'MerchantTradeNo' => $contribution_trxn_id,
      'TimeStamp' => time(),
    );
    _civicrm_allpay_checkmacvalue($post_data, $processor);
    $json = FALSE;
    $response = _civicrm_allpay_postdata($payment_processor['url_api'], $post_data, $json);
  }
}