PayU BharatKosh Encryption Wrapper - Flutter Plugin #

A Flutter plugin that wraps the native PayU BharatKosh encryption wrapper SDKs for Android and iOS, providing a unified Dart API for Flutter apps.

Overview #

This plugin is a thin wrapper that uses the existing native SDKs:

• Android: payu-cp-encryption-wrapper (via Maven)
• iOS: PayUIndia-CP-Encryption-SDK (via CocoaPods)

The plugin only contains the Flutter platform channel bridge code - all encryption/decryption logic remains in the native SDKs.

Features #

• Request Decryption: Decrypts encrypted payloads from BharatKosh
• Response Encryption: Encrypts CheckoutPro responses before sending back to BharatKosh
• Hash Generation: Handles hash generation for CheckoutPro SDK
• Cancel & Error Handling: Proper handling of user cancellation and error scenarios
• Dual API Support: Both callback-based and async/await approaches

Installation #

Step 1: Add Flutter Plugin Dependency #

Add this to your pubspec.yaml:

dependencies:
  payu_bharatkosh_encryption_wrapper:
    path: path/to/payu_bharatkosh_encryption_wrapper

Step 2: Android Setup #

Add the Maven repositories to your android/settings.gradle:

dependencyResolutionManagement {
    repositories {
        google()
        mavenCentral()
        maven { url "https://maven.payu.in" }
        maven { url "https://central.sonatype.com/repository/maven-snapshots/" }
    }
}

Ensure minimum SDK is 24 in android/app/build.gradle:

android {
    defaultConfig {
        minSdk 24
    }
}

Step 3: iOS Setup #

Ensure your ios/Podfile has the correct platform:

platform :ios, '13.0'

target 'Runner' do
  use_frameworks!
  flutter_install_all_ios_pods File.dirname(File.realpath(__FILE__))
end

Run pod install:

cd ios
pod install

Usage #

Import the package #

import 'package:payu_bharatkosh_encryption_wrapper/payu_bharatkosh_encryption_wrapper.dart';

Method 1: Using Callback (Traditional) #

final wrapper = BharatkoshWrapper();

wrapper.startPayment(
  encRequestParameter: 'encrypted_payload_from_bharatkosh',
  reqDigitalSignature: 'digital_signature_from_bharatkosh',
  merchIdVal: 'merchant_id',
  isProduction: false, // true for production
  callback: MyPaymentCallback(),
);

class MyPaymentCallback implements BharatkoshWrapperCallback {
  @override
  void onSuccess(String encryptedResponse) {
    // Payment successful - send encryptedResponse to BharatKosh
    print('Payment Success: $encryptedResponse');
  }

  @override
  void onFailure(String encryptedResponse) {
    // Payment failed - send encryptedResponse to BharatKosh
    print('Payment Failed: $encryptedResponse');
  }

  @override
  void onCancel(String encryptedResponse) {
    // User cancelled - send encryptedResponse to BharatKosh
    print('Payment Cancelled: $encryptedResponse');
  }

  @override
  void onError(String encryptedResponse) {
    // Error occurred - send encryptedResponse to BharatKosh
    print('Payment Error: $encryptedResponse');
  }
}

Method 2: Using async/await (Modern) #

final wrapper = BharatkoshWrapper();

try {
  final result = await wrapper.startPaymentAsync(
    encRequestParameter: 'encrypted_payload_from_bharatkosh',
    reqDigitalSignature: 'digital_signature_from_bharatkosh',
    merchIdVal: 'merchant_id',
    isProduction: false, // true for production
  );

  switch (result.type) {
    case BharatkoshResultType.success:
      print('Payment successful: ${result.encryptedResponse}');
      break;
    case BharatkoshResultType.failure:
      print('Payment failed: ${result.encryptedResponse}');
      break;
    case BharatkoshResultType.cancel:
      print('Payment cancelled: ${result.encryptedResponse}');
      break;
    case BharatkoshResultType.error:
      print('Payment error: ${result.encryptedResponse}');
      break;
  }

  // Send result.encryptedResponse back to BharatKosh
} catch (e) {
  print('Exception: $e');
}

API Reference #

BharatkoshWrapper #

The main class for interacting with the BharatKosh encryption wrapper.

startPayment()

Starts the payment flow using a callback.

Future<void> startPayment({
  required String encRequestParameter,
  required String reqDigitalSignature,
  required String merchIdVal,
  required bool isProduction,
  required BharatkoshWrapperCallback callback,
})

startPaymentAsync()

Starts the payment flow and returns a Future with the result.

Future<BharatkoshPaymentResult> startPaymentAsync({
  required String encRequestParameter,
  required String reqDigitalSignature,
  required String merchIdVal,
  required bool isProduction,
})

Parameters #

BharatkoshWrapperCallback #

Abstract class for receiving payment callbacks.

BharatkoshPaymentResult #

Result object returned by startPaymentAsync().

BharatkoshResultType #

Enum representing the result type.

Environment Configuration #

The plugin supports two environments:

• UAT (Test): isProduction: false

  • Base URL: https://compulsiveuat.payu.in/

• Production: isProduction: true

  • Base URL: https://compulsive.payu.in/

Project Structure #

CPWrapperFlutter/payu_bharatkosh_encryption_wrapper/
├── lib/                           # Dart API
│   ├── payu_bharatkosh_encryption_wrapper.dart
│   └── src/
│       ├── bharatkosh_wrapper.dart
│       ├── bharatkosh_wrapper_callback.dart
│       └── bharatkosh_payment_result.dart
│
├── android/                       # Android Plugin (thin bridge)
│   └── src/main/kotlin/.../PayuBharatkoshEncryptionWrapperPlugin.kt
│
├── ios/                           # iOS Plugin (thin bridge)
│   └── Classes/PayuBharatkoshEncryptionWrapperPlugin.swift
│
└── example/                       # Example Flutter App

Requirements #

• Flutter: 3.0.0 or later
• Dart: 3.0.0 or later
• Android: API 24 (Android 7.0) or later
• iOS: 13.0 or later

Native SDK Dependencies #

Documentation #

For comprehensive integration guide, see:

• Flutter Integration Guide
• PayU Developer Documentation

Support #

For issues and questions:

• Create an issue in the repository
• Contact PayU support team

License #

MIT License