Xahau Hook and CronSet Transaction Examples

This repository contains examples for managing hooks and creating scheduled hook callbacks on the Xahau network.

Overview

This project demonstrates how to:

• Install and uninstall hooks on Xahau accounts
• Configure account settings for hook collection
• Schedule automated hook callbacks using CronSet transactions

CronSet is a transaction type on Xahau that allows you to schedule automated hook callbacks at specified intervals. This is useful for triggering hook logic on a recurring basis without manual intervention.

Files

Hook Management

• installHook.js - Installs a hook on your account using a HookHash
• uninstallHook.js - Removes/deletes an installed hook from your account
• accountSet.js - Activates the asfTshCollect flag to enable Transaction Signature Hook Collection

CronSet Management

• cronSet.js - Creates a CronSet transaction to schedule hook callbacks
• cronUnset.js - Removes an existing CronSet transaction

Configuration

• package.json - Dependencies and scripts configuration

Installation

1. Clone this repository
2. Install dependencies:

npm install

Configuration

Before running the scripts, you need to configure your account seed in both cronSet.js and cronUnset.js:

const seed = 'snYourSeedHere'; // Replace with your actual seed, get one at https://xahau-test.net/

Important: The seed is your private key (starts with 's'), NOT your account address (which starts with 'r'). The address will be automatically derived from the seed.

You can get testnet credentials and XAH from: https://xahau-test.net

Usage

Hook Management

Before using CronSet transactions, you need to have a hook installed on your account.

Installing a Hook

To install a hook on your account:

node installHook.js

This script installs a hook using the following HookHash:

83A41BE45166B33E66EF653512396409E1BF9FA85A7C15D0ABC81C24E2890CB3

The transaction uses:

• Flags: 4 (hsfCOLLECT) - Enables hook collection/callback functionality
• HookOn: FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFFFFFFFFFFFBFFFFF - Defines which transaction types trigger the hook

Important: Make sure to update your seed in the file before running.

Activating Hook Collection

If you need to enable Transaction Signature Hook Collection:

node accountSet.js

This sets the asfTshCollect flag (flag 11) on your account using an AccountSet transaction.

Uninstalling a Hook

If you need to remove the hook from your account for any reason:

node uninstallHook.js

This removes the installed hook by setting Flags: 1 with an empty CreateCode field.

CronSet Management

Once you have a hook installed, you can schedule it to run automatically.

Creating a CronSet

To schedule hook callbacks:

npm run set-cron

Or directly:

node cronSet.js

This will create a CronSet transaction with the following parameters:

• StartTime: When to begin execution (Ripple Epoch timestamp, or 0 for immediate)
• RepeatCount: Number of times to trigger the hook (default: 3)
• DelaySeconds: Delay between each execution in seconds (default: 120 seconds / 2 minutes)

Removing a CronSet

To remove an existing scheduled cron job:

npm run unset-cron

Or directly:

node cronUnset.js

This sends a CronSet transaction with Flags: 1 (tfCronUnset) to remove the existing cron job.

Transaction Formats

SetHook (Install Hook)

{
  "TransactionType": "SetHook",
  "Account": "<your account address>",
  "Hooks": [
    {
      "Hook": {
        "HookHash": "83A41BE45166B33E66EF653512396409E1BF9FA85A7C15D0ABC81C24E2890CB3",
        "HookNamespace": "0000000000000000000000000000000000000000000000000000000000000000",
        "HookOn": "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFFFFFFFFFFFBFFFFF",
        "Flags": 4 // hsfCOLLECT - Enables hook collection/callback functionality
      }
    }
  ]
}

Important: The Flags: 4 (hsfCOLLECT) goes inside the Hook object to enable hook collection/callback functionality.

SetHook (Uninstall Hook)

{
  "TransactionType": "SetHook",
  "Account": "<your account address>",
  "Hooks": [
    {
      "Hook": {
        "CreateCode": "",
        "Flags": 1
      }
    }
  ]
}

AccountSet (Enable Hook Collection)

{
  "TransactionType": "AccountSet",
  "Account": "<your account address>",
  "SetFlag": 11 // asfTshCollect
}

CronSet (Create)

{
  "TransactionType": "CronSet",
  "Account": "<hook account address>",
  "StartTime": <Ripple Epoch timestamp or 0>,
  "RepeatCount": 3,
  "DelaySeconds": 120
}

CronSet (Remove)

{
  "TransactionType": "CronSet",
  "Account": "<hook account address>",
  "Flags": 1  // tfCronUnset
}

Note: When removing a CronSet, you must omit StartTime, RepeatCount, and DelaySeconds, and set Flags: 1.

Ripple Epoch Conversion

Xahau uses Ripple Epoch time (seconds since January 1, 2000 00:00 UTC) instead of Unix timestamps.

To convert:

const RIPPLE_EPOCH_OFFSET = 946684800;
const rippleEpochTime = Math.floor(Date.now() / 1000) - RIPPLE_EPOCH_OFFSET;

Dependencies

• xahau (^4.0.2) - Xahau JavaScript library
• xrpl-accountlib (^9.1.0) - Account utilities for signing and submitting transactions

Network

The examples connect to the Xahau testnet:

wss://xahau-test.net

How It Works

1. The script connects to the Xahau network
2. Derives account information from your seed
3. Fetches network values (fee, sequence, last ledger sequence, network ID)
4. Constructs the CronSet transaction
5. Signs and submits the transaction
6. Displays the transaction result

Example Output

Account: rYourAccountAddress
Connected to Xahau
Prepared CronSet transaction: {
  "TransactionType": "CronSet",
  "Account": "rYourAccountAddress",
  "StartTime": 816348759,
  "RepeatCount": 3,
  "DelaySeconds": 120,
  "Fee": "12",
  "Sequence": 123456,
  "LastLedgerSequence": 123531,
  "NetworkID": 21338
}
Transaction result: { ... }
Disconnected from Xahau

Security Notes

• Never commit your seed to version control
• Keep your seed secure and private
• Use environment variables for production deployments
• Only use testnet seeds for testing

License

MIT

Resources

• Xahau Website
• Xahau Documentation
• Xahau Testnet Faucet