LayerZero V2 Vyper Module

A Vyper module for LayerZero V2 cross-chain messaging with example implementation.

Overview

This repository contains:

• LayerZeroV2.vy: Base module for LayerZero V2 messaging
• ExampleMessenger.vy: Example implementation for string messaging
• Tests for module functionality

Contracts

LayerZeroV2

Base module that handles core LayerZero V2 functionality:

• Message sending with fee management
• Message receiving with security checks
• Peer management
• Gas limit configuration

Key features:

• Adjustable message size (LZ_MESSAGE_SIZE_CAP)
• Security checks for trusted peers
• Fee quoting and payment handling
• Designed for module imports

Example Messenger

Example implementation showing how to use the LZ module:

• String message sending across chains
• Message receiving and conversion
• Ownable management for security
• Gas limit configuration

Features:

• String messages up to 128 bytes
• Owner-controlled peer management
• Event emission for tracking
• Example of proper module initialization

Testing

Tests cover:

1. Message Sending

   • Fee quoting
   • Peer management
   • Event emission

2. Message Receiving

   • Security checks
   • Message conversion
   • Event verification

3. Security

   • Endpoint verification
   • Peer validation
   • Owner controls

Usage

Module Import

import LayerZeroV2 as lz
initializes: lz
exports: (
    lz.LZ_ENDPOINT,
    lz.LZ_PEERS,
    lz.LZ_MESSAGE_SIZE_CAP,
    lz.default_gas_limit,
    lz.quote_lz_fee,
)

Initialization

@deploy
def __init__(_endpoint: address, _gas_limit: uint256):
    lz.__init__(_endpoint, _gas_limit)

Sending Messages

@payable
@external
def send_message(_dst_eid: uint32, _receiver: address, _message: String[128]):
    encoded: Bytes[lz.LZ_MESSAGE_SIZE_CAP] = convert(_message, Bytes[lz.LZ_MESSAGE_SIZE_CAP])
    lz._send_message(_dst_eid, _receiver, encoded)

Receiving Messages

@payable
@external
def lzReceive(_origin: lz.Origin, _message: Bytes[lz.LZ_MESSAGE_SIZE_CAP], ...):
    assert lz._lz_receive(...)
    message: String[128] = convert(_message, String[128])

Development

Requirements:

• Python 3.9+
• Vyper ~=0.4
• LayerZero V2 endpoint deployment

Testing:

# Setup virtual environment
uv venv
uv sync
source venv/bin/activate

# Run all tests
pytest tests/

Security

Always ensure proper peer setup and ownership management when deploying. Code has not been audited yet and probably contains bugs.