Category: Payment Gateways

When building a secure online donation platform in the UAE, choosing a trusted government backed payment gateway is critical. Dubai Pay provides a reliable and compliant infrastructure that enables organisations to collect payments safely while meeting regulatory standards.

In this guide, we walk through the complete process of integrating Dubai Pay into a PHP application. The implementation is demonstrated in the context of developing an online donation system for Dubai Cares, covering authentication, payment creation, signature validation, and transaction confirmation. The aim is to clearly explain each step so developers can understand both the technical flow and the security principles behind the integration.

Results

QA credential requirements

OAuth authentication

Required keys for authorisation

HMAC SHA512 signature generation

Payment registration and redirect handling

Token verification and confirmation

Hosted versus self managed checkout

Understanding the Dubai Pay Architecture

Dubai Pay uses:

• OAuth 2 client credentials flow for authentication
• Bearer token based API authorisation
• HMAC SHA512 signature validation for request integrity
• Batch based transaction processing
• Hosted redirection checkout model

The gateway is designed to ensure:

• Payload integrity
• Non tampering of transaction data
• Secure government compliant processing
• Clear batch reconciliation

Required QA Credentials

Before integration begins, you must obtain QA environment credentials from Dubai Pay.

Step 1: OAuth Authentication

Dubai Pay requires a Bearer access token before any API call can be made.

Generating Access Token

function getAccessToken($clientId, $clientSecret)


{


$url = “https://ids.qa.dubai.gov.ae/oauth2/token”;


$credentials = base64_encode($clientId . “:” . $clientSecret);


$ch = curl_init($url);


curl_setopt_array($ch, [


CURLOPT_RETURNTRANSFER => true,


CURLOPT_POST => true,


CURLOPT_HTTPHEADER => [


“Authorization: Basic ” . $credentials,


“Content-Type: application/x-www-form-urlencoded”


],


CURLOPT_POSTFIELDS => http_build_query([


“grant_type” => “client_credentials”,


“scope” => “openid”


])


]);


$response = curl_exec($ch);


curl_close($ch);


$data = json_decode($response, true);


if (!isset($data[‘access_token’])) {


die(“OAuth authentication failed.”);


}


return $data[‘access_token’];


}

This token must be included in every subsequent API request:

Authorization: Bearer {access_token}

Step 2: Generating HMAC SHA512 Signature

Every Dubai Pay API request requires a signature header called:

dubaiPaySignature

The signature is created from:

• The exact JSON payload
• SHA512 hashing
• The Checksum Key
• Uppercase output

Signature Example

$jsonPayload = json_encode($jsonPayload = json_encode(

$jsonPayload = json_encode(

$payload,

JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE

);

$jsonPayload = mb_convert_encoding($jsonPayload, ‘UTF-8’);

$signature = strtoupper(

hash_hmac(‘sha512’, $jsonPayload, $CHECKSUM_KEY)

);

$payload,

JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE

);

$jsonPayload = mb_convert_encoding($jsonPayload, ‘UTF-8’);

$signature = strtoupper(

hash_hmac(‘sha512’, $jsonPayload, $CHECKSUM_KEY)

);

This ensures:

• Payload integrity
• Tamper prevention
• Government grade request validation

Step 3: Creating the Payment and Getting Redirect URL

Dubai Pay follows a hosted redirection model. You register a batch transaction, and the response contains a uri for redirection.

callAPI Helper Function

function callAPI($endpoint, $payload, $token, $baseUrl, $checksumKey)


{


$jsonPayload = json_encode(


$payload,


JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE


);


$jsonPayload = mb_convert_encoding($jsonPayload, ‘UTF-8’);


$signature = strtoupper(


hash_hmac(‘sha512’, $jsonPayload, $checksumKey)


);


$ch = curl_init($baseUrl . $endpoint);


curl_setopt_array($ch, [


CURLOPT_RETURNTRANSFER => true,


CURLOPT_POST => true,


CURLOPT_HTTPHEADER => [


“Authorization: Bearer $token”,


“Content-Type: application/json”,


“dubaiPaySignature: $signature”


],


CURLOPT_POSTFIELDS => $jsonPayload


]);


$response = curl_exec($ch);


curl_close($ch);


return json_decode($response, true);


}

Creating the Payment

$accessToken = getAccessToken($CLIENT_ID, $CLIENT_SECRET);


$payload = [


“entityCode” => $ENTITY_CODE,


“batchId” => “batch_” . time(),


“totalAmount” => 10.00,


“totalTransactions” => 1,


“returnUrl” => $RETURN_URL,


“transactions” => [[


“spCode” => $SP_CODE,


“servCode” => $SERV_CODE,


“spTrn” => uniqid(“DONATION_”),


“amount” => 10.00,


“currency” => “AED”,


“timestamp” => date(“d-m-Y H:i:s”),


“channel” => “100”,


“description” => “Online Donation”,


“type” => “sale”,


“version” => “2.1”,


“settlementType” => “gov”


]]


];

Calling Register Endpoint

$response = callAPI(


“/secure/dubaipay/batch/1.0.0/register”,


$payload,


$accessToken,


$BASE_URL,


$CHECKSUM_KEY


);


Redirecting the Donor


if (!isset($response[‘uri’])) {


die(“Payment registration failed.”);


}


header(“Location: ” . $response[‘uri’]);


exit;

The donor is redirected to Dubai Pay secure hosted checkout.

Hosted Checkout Versus Self Managed Checkout

Dubai Pay primarily supports hosted redirection checkout.

This means:

• Card data is entered on Dubai Pay servers
• Your server does not handle card details
• PCI scope is reduced
• Security responsibility is simplified

Direct self managed card form processing is not the standard model.

Step 4: Handling Payment Confirmation

After payment completion, Dubai Pay posts a TOKEN to your return URL.

Retrieve Token

$responseToken = $_POST[‘TOKEN’];

Verify Using tokenDetails API

$verification = callAPI(


   “/secure/dubaipay/batch/1.0.0/tokenDetails”,


   [


       “token” => $responseToken,


       “entityCode” => $ENTITY_CODE


   ],


   $accessToken,


   $BASE_URL,


   $CHECKSUM_KEY


);

Validate Transaction

if (


   $verification[‘batchStatus’] == ‘completed’ &&


   $verification[‘transactions’][0][‘message’][‘code’] == 0


) {

Only when both conditions are satisfied should the transaction be considered successful.

Step 5: Confirm API Call

Dubai Pay recommends confirming transactions after successful verification.

$confirmPayload = [


   “entityCode” => $ENTITY_CODE,


   “batchId”    => $verification[‘batchId’],


   “confirmAll” => true,


   “message” => [


       “code” => “0”,


       “text” => “confirmed”


   ]


];

$confirmResponse = callAPI(


   “/secure/dubaipay/batch/1.0.0/confirm”,


   $confirmPayload,


   $accessToken,


   $BASE_URL,


   $CHECKSUM_KEY


);

Only after confirmation should you:

• Update the donation record
• Store the gateway reference
• Trigger receipt email
• Mark transaction as settled

Security and Production Best Practices

When moving from QA to production:

• Replace QA endpoints with production URLs
• Update Client ID and Client Secret
• Replace Checksum Key
• Validate return URL handling
• Log all API responses
• Use idempotent transaction references
• Implement server side validation