Step 1: Include the SDK in your Application

Include the SDK in your application’s build.gradle:

implementation 'in.payu:native-otp-assist:1.3.2'

Compatibility

Min SDK Version: 21
Compile SDK Version: 31 or later

Step 2: Set up Payment Hash and Post Data

Generate Payment Hash

For more information on the generation of Payment Hash, refer to Hash Generation.

Note: Every transaction (payment or non-payment) needs a hash set up by you before sending the transaction details to PayU. Hash is required for PayU to validate the authenticity of the transaction. This hashing should be done on your server.

Payment Post Data

Note: Use the Core SDK library to generate payment post data.

Step 3: Initiate Payment

Initialize Native OTP SDK

Initialize the Native OTP Assist SDK by providing the PayUOtpAssistConfig object having post data and reference to PayUOtpAssistCallback to listen to the SDK events similar to the following code block:

Note: Ensure that you configure the Internet permission in your manifest file:

<uses-permission android:name="android.permission.INTERNET" />

PayU fetches the OTP through RECEIVE_SMS if the RECEIVE_SMS permission is granted. Otherwise, fetch the OTP using the Google Consent API. To understand the flow, refer to PayU OTP Parser.

Callbacks

The following is a list of callback functions provided by PayUOtpAssistCallback class:

fun onPaymentSuccess(merchantResponse: String?, payUResponse: String?): Called when payment succeeds. merchantResponse:
fun onPaymentFailure(merchantResponse: String?, payUResponse: String?): Called when payment fails.
fun onError(errorCode: String?, errorMessage: String?): Called when we got some error where:
- errorCode : Error Code
- errorMessage : Error Description
fun shouldHandleFallback(payUAcsRequest: PayUAcsRequest) : Boolean – It’s an optional callback, override when you want to handle the Bank page redirection flow. You just need to change the return value to false. You can also open CustomeBrowser in fallback scenarios. The following code snippet is to launch the CustomBrowser.

You will get PayUAcsRequest on shouldHandleFallback() callback. Whether you will get issuerUrl and issuerPostData or acsTemplate on PayUAcsRequest.acsTemplate is the HTML string that you need to load to the Web view.

PayUAcsRequest field	Description
issuerUrl	It’s the Bank/ACS page Url.
issuerPostData	You need to load issuerUrl to the Webview along with this issuerPostdata string. Ex: webView.postUrl(issuerUrl, issuerPostData.toByteArray())
acsTemplate	If issuerUrl is empty, you need to load acsTemplate to the Webview. Ex: webView.loadData(acsTemplate, “text/html”, “UTF-8”);

The following table lists error codes and their description:

Error Code	Description
1001	No Internet
1002	Network timeout, please verify with your server.
1003	Gateway timeout, please verify with your server.
1004	User cancelled it, please verify with your server.
1005	Something went wrong, please verify with your server.
1006	The bank page timed out, please verify with your server.

Note: After you get the response from SDK, make sure to confirm it with the PayU server. It is recommended to implement the PayU Webhook or backend verify call from your backend.

Step 4: Verify the Transaction using Webhook

After you get the response from SDK, make sure to confirm it with the PayU server.

Note: It is recommended to implement the PayU Webhook or backend verify call from your backend.

Webhook is a server-to-server callback. Once this feature is activated for merchants, PayU would send an S2S response, in addition to SDK callback, to the merchant. It is recommended for the merchant to process the transaction order status – based upon the S2S response and not via the Browser Redirection/SDK callback response to ensure optimum translation outcomes. For more information on the Webhook implementation, refer to Web Checkout Integration Documentation > Webhooks,

Also, you can verify payment through polling, the transaction status after the SDK callback from your backend. For more information, refer to Verify the Transaction.