LayerZero - omni chain contracts

• TODO: add MNEMONIC to .env file

Read Whitepaper

LayerZero relies on two parties to transfer messages between on-chain endpoints:

• The Oracle &
• The Relayer

LayerZero enables devs to send secure messages across blockchains.

Omnichain Interoperability Protocol

LayerZero Endpoint has a non-reentrancy guard for both the send() and receive(), respectively. In other words, both send() and receive() can not call themselves on the same chain.

Setup the project

npm install

Run tests

npx hardhat test

NOTE: You must add a .env with a MNEMONIC that is funded on testnets !

configure an .env file to have the values of .env.example and test deploy! (Use a real LayerZero endpoint in place of 0x0000..)

• TODO: real LayerZero endpoints

Testing Cross Chain Messages

1. Deploy both OmniCounters:

npx hardhat --network fuji deploy
npx hardhat --network mumbai deploy 

2. Set the remote addresses, so each contract can receive messages

npx hardhat --network mumbai omniCounterSetRemote --target-network fuji
npx hardhat --network fuji omniCounterSetRemote --target-network mumbai

3. Send a cross chain message from mumbai to fuji !

npx hardhat --network mumbai omniCounterIncrementCounter --target-network fuji

Optionally use this command in a separate terminal to watch the counter increment in real-time.

npx hardhat --network fuji omniCounterPoll    

Testing Multiple Cross Chain Messages

1. Deploy both OmniCounters:

npx hardhat --network mumbai deploy 
npx hardhat --network fuji deploy
npx hardhat --network bsc-testnet deploy 
npx hardhat --network fantom-testnet deploy 

2. Set the remote addresses, so each contract can receive messages

npx hardhat --network mumbai omniCounterSetRemote --target-network fuji
npx hardhat --network fuji omniCounterSetRemote --target-network mumbai

npx hardhat --network mumbai omniCounterSetRemote --target-network bsc-testnet
npx hardhat --network bsc-testnet omniCounterSetRemote --target-network mumbai

npx hardhat --network mumbai omniCounterSetRemote --target-network fantom-testnet
npx hardhat --network fantom-testnet omniCounterSetRemote --target-network mumbai

3. Send a cross chain message from mumbai to fuji !

npx hardhat --network mumbai omniCounterIncrementMultiCounter --target-networks fuji,bsc-testnet,fantom-testnet

Optionally use this command in a separate terminal to watch the counter increment in real-time.

npx hardhat --network fuji omniCounterPoll
npx hardhat --network bsc-testnet omniCounterPoll
npx hardhat --network fantom-testnet omniCounterPoll

For further reading, and a list of endpoint ids and deployed LayerZero contract addresses please take a look at the Gitbook here: https://layerzero.gitbook.io/

Read the currently set Oracle

npx hardhat --network mumbai omniCounterGetOracle --target-network fantom-testnet

Set a custom Oracle for the deployed OmniCounter

npx hardhat --network mumbai omniCounterSetOracle --target-network mumbai --oracle 0xORACLE_ADDR

See some examples in /contracts 🙌

test LayerZero locally using LayerZeroEndpointMock.sol