Custom Action implementation to encrypt a payload sent to the API

encrypt_with_aes_nonce.dart

import 'dart:convert';
import 'package:encrypt/encrypt.dart' as en;

Future<String> encryptWithAesNonce(
  dynamic jsonPayload,
  String aesKeyString,
  String nonceKeyString,
) async {
  try {
    
    // Your function code goes here
    print("JSON Payload:");
    print(jsonPayload);
    print(jsonPayload.runtimeType);

    final data = json.encode(jsonPayload);
    print(data);

    final key = en.Key.fromBase64(aesKeyString);
    final nonceKey = nonceKeyString;
    final nonce = base64Url.decode(nonceKey);

    final encrypter = en.Encrypter(en.AES(key, mode: en.AESMode.cbc));
    final encrypted = encrypter.encrypt(data, iv: en.IV(nonce));

    print(encrypted);
    print(encrypted.base64);

    return encrypted.base64;
  } catch (e) {
    
    // Handle the exception
    print('An error occurred: $e');

    // For demonstration, let's return a simple error message.
    return 'Error: Encryption failed';
    
  } finally {
    
    // Optional: This block executes regardless of whether an exception occurred or not.
    print('Encryption attempt finished.');
    
  }
}