Avixolabs Documentation

<?php
// Postback URL handler for Avixolabs
// 1. Configuration
$secretKey = "YOUR_SECRET_KEY_HERE"; // Get from dashboard
$allowedIPs = ['192.168.1.1', '10.0.0.1']; // Add allowed IPs here

// 2. Security check - IP validation (optional but recommended)
$clientIP = $_SERVER['HTTP_X_FORWARDED_FOR'] ?? $_SERVER['REMOTE_ADDR'];
if (!in_array($clientIP, $allowedIPs)) {
    http_response_code(403);
    die("Access denied: Invalid IP");
}

// 3. Get POST parameters
$subId = $_POST['subId'] ?? '';
$transId = $_POST['transId'] ?? '';
$reward = $_POST['reward'] ?? 0;
$status = $_POST['status'] ?? 1;
$signature = $_POST['signature'] ?? '';

// 4. Validate required parameters
if (empty($subId) || empty($transId) || empty($signature)) {
    http_response_code(400);
    die("Missing required parameters");
}

// 5. Validate signature
$expectedSignature = md5($subId . $transId . $reward . $secretKey);
if (!hash_equals($expectedSignature, $signature)) {
    http_response_code(401);
    die("Invalid signature");
}

// 6. Check for duplicate transaction (prevent double processing)
function isDuplicateTransaction($transactionId) {
    // Implement your duplicate check logic here
    // Example: Check database for existing transaction
    // return checkIfTransactionExists($transactionId);
    return false;
}

if (isDuplicateTransaction($transId)) {
    echo "ok"; // Already processed, respond ok
    exit;
}

// 7. Handle status (1 = credit, 2 = chargeback)
if ($status == 2) {
    // Chargeback - subtract reward from user
    $reward = -abs($reward);
} else {
    // Normal credit - ensure positive value
    $reward = abs($reward);
}

// 8. Process the transaction
try {
    // Add your transaction processing logic here
    // Example: creditUser($subId, $reward, $transId);
    
    // Log the transaction
    // logTransaction($transId, $subId, $reward, $status);
    
    // 9. Store transaction to prevent duplicates
    // storeTransaction($transId);
    
    // 10. Success response
    header('Content-Type: text/plain');
    echo "ok";
    
} catch (Exception $e) {
    // Log error
    error_log("Postback error: " . $e->getMessage());
    
    // Return error (our system will retry)
    http_response_code(500);
    die("Error processing transaction");
}

/**
 * Helper function examples
 */

function creditUser($userId, $amount, $transactionId) {
    // Implement your user credit logic
    // Update user balance in your database
}

function logTransaction($transactionId, $userId, $amount, $status) {
    // Implement your logging logic
    // Save to database or log file
}

function storeTransaction($transactionId) {
    // Store transaction ID to prevent duplicates
    // Save to database or cache
}

function checkIfTransactionExists($transactionId) {
    // Check if transaction already processed
    // Query database or cache
    return false;
}
?>