Webhooks

{
  "data": {
    "clientOrg": {
      "name": "Health_Plan_ABC_Division"
    },
    "clientOrgWebHook": {
      "url": "https://your-app.com/webhooks/lynx",
      "encryptionIndicator": true,
      "deliveryMode": "AtLeastOnce"
    }
  },
  "idempotency": {
    "idempotencyKey": "cf82639c-e3b6-4d51-9871-0e452a2b1566"
  }
}

public static String decrypt(String secretKey, String initializationVector, String cipherText) throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidAlgorithmParameterException, InvalidKeyException, IllegalBlockSizeException, BadPaddingException {
  // Initialize GCM Parameters
  // Same base64EncodeKey, IV and GCM Specs are to be used for encryption and decryption.
  GCMParameterSpec gcmParameterSpec = new GCMParameterSpec(TAG_BIT_LENGTH, Base64.getDecoder().decode(initializationVector));
  Cipher decryptCypher = Cipher.getInstance(AES);
  decryptCypher.init(Cipher.DECRYPT_MODE, convertStringToSecretKey(secretKey), gcmParameterSpec, drbgSecureRandom());
  byte[] plainTextArray = null;

  plainTextArray = decryptCypher.doFinal(Base64.getDecoder().decode(cipherText));

  return new String(plainTextArray);
}

/**
  * Create a SecretKey object from a given base64 secretKey string
  * @param secretKey inbound secret key as string encoded in base64
  * @return the SecretKey type object
  */
public static SecretKey convertStringToSecretKey(String secretKey) {
  byte[] decodedKey = Base64.getDecoder().decode(secretKey);
  return new SecretKeySpec(decodedKey, 0, decodedKey.length, "AES");
}

// NPM module required to decrypt (npm install crypto)
const crypto = require('crypto');

/**
 * The decrypt function decrypts the inbound encrypted message. All inbound 
 * parameters are base64 encoded.
 */
const decrypt = function(encryptedMsg, secret, iv) {
  // decode base64 message
  const bufferData = Buffer.from(encryptedMsg, 'base64');
  // separate message body and tag from message
  let msg = bufferData.slice(0, bufferData.length - 16);
  let authTag = bufferData.slice(bufferData.length - 16, bufferData.length);

  // decode base64 secret and init vector
  let decodedSecret = Buffer.from(secret, 'base64');
  let decodedIV = Buffer.from(iv, 'base64');

  // decrypt message body
  let decipher = crypto.createDecipheriv('aes-256-gcm', decodedSecret, decodedIV);
  decipher.setAuthTag(authTag);
  let decipheredText = decipher.update(msg, 'utf8');
  decipheredText += decipher.final('utf8');
  console.log(decipheredText)
};