Skip to content

Latest commit

 

History

History
173 lines (142 loc) · 5.58 KB

sample.md

File metadata and controls

173 lines (142 loc) · 5.58 KB

Sample Code for Creating an Interchain Proposal

This document outlines how to create a proposal that sets a new string value in a DummyState.sol deployed on Avalanche from Ethereum.

Prerequisites

You must have deployed instances of InterchainProposalSender and InterchainProposalExecutor. Your InterchainProposalSender must be whitelisted for the InterchainProposalExecutor.

Code Snippet

1. Wallet and Contract Setup

import { Contract, Wallet } from "ethers";
import {
  CHAINS,
  Environment,
  AxelarQueryAPI,
} from "@axelar-network/axelarjs-sdk";

// ABI for the relevant contracts
const senderABI = [...];
const governorAlphaABI = [...];

// Contract addresses
const DummyContractAddressOnAvalanche = "0xDummyContractAddressOnAvalanche";
const ProposalExecutorAddressOnAvalanche =
  "0xProposalExecutorAddressOnAvalanche";
const GovernorAlphaAddressOnEthereum = "0xGovernorAlphaAddressOnEthereum";
const InterchainProposalSenderAddressOnEthereum =
  "0xInterchainProposalSenderAddressOnEthereum";

// Set up your wallet
const signer = new ethers.Wallet("YOUR_EVM_PRIVATE_KEY");

// Initialize the contracts
const governorAlphaContract = new Contract(
  GovernorAlphaAddressOnEthereum,
  governorAlphaABI,
  signer
);
const sender = new Contract(
  InterchainProposalSenderAddressOnEthereum,
  senderABI,
  signer
);

This part of the script sets up your wallet and initializes the GovernorAlpha and InterchainProposalSender contracts on Ethereum.

2. Gas Fee Estimation

// Axelar API setup for gas gas estimation
const axelarApi = new AxelarQueryAPI({ environment: Environment.MAINNET });

// Estimate Axelar Relayer gas for execution on the destination chain
const relayerFee = await axelarApi.estimateGasFee(
  CHAINS.MAINNET.ETHEREUM,
  CHAINS.MAINNET.AVALANCHE,
  GasToken.ETH,
  1_000_000, // Estimated gas limit needed for executing your transaction on the destination chain
  1.2, // Multiplier for overestimation
  undefined
);

Here, the script estimates the gas gas for the execution of your transaction on the destination chain using Axelar API.

3. Choose Which Chains Will Execute the Proposal

You can opt to execute your proposal on a single destination chain or multiple chains.

Single Destination Chain

Proposal Payload Encoding

const proposalExecutions = [
  {
    target: dummyState.address,
    value: 0,
    callData: new ethers.utils.Interface([
      "function setState(string)",
    ]).encodeFunctionData("setState", ["Hello World"]),
  },
];

This step encodes the proposal payload, which is then dispatched to the destination chain. This payload represents the specific transaction you want to execute.

Proposing Transaction to the Governor Contract

// Propose the payload to the Governor contract
await governorAlphaContract.propose(
  [sender.address],
  [relayerFee], // The `relayerFee` from step 2 is used here.
  ["sendProposal(string,string,(address,uint256,bytes)[])"],
  [
    ethers.utils.defaultAbiCoder.encode(
      ["string", "string", "(address target, uint256 value, bytes callData)[]"],
      ["Avalanche", ProposalExecutorAddressOnAvalanche, proposalExecutions]
    ),
  ],
  `A proposal to set "Hello World" message at Avalanche chain`
);

Multiple Destination Chains

If you wish to propose to multiple chains, use a similar approach to the single destination chain, but use the sendProposals function like the following:

const proposalExecutions = [
  {
    destinationChain: "Avalanche",
    destinationContract: ProposalExecutorAddressOnAvalanche,
    gas: ethers.utils.parseEther(relayerFee),
    calls: [
      {
        target: dummyState.address,
        value: 0,
        callData: new ethers.utils.Interface([
          "function setState(string)",
        ]).encodeFunctionData("setState", ["Hello World"]),
      },
    ],
  },
  {
    destinationChain: "Fantom",
    destinationContract: ProposalExecutorAddressOnFantom,
    gas: ethers.utils.parseEther(relayerFee2), // Note that the relayer gas must be calculated separately for each execution.
    calls: [
      {
        target: dummyState.address,
        value: 0,
        callData: new ethers.utils.Interface([
          "function setState(string)",
        ]).encodeFunctionData("setState", ["Hello World"]),
      },
    ],
  },
];

Proposing Transaction to the Governor Contract

// Propose the payload to the Governor contract
await governorAlphaContract.propose(
  [sender.address],
  [relayerFee], // The `relayerFee` from step 2 is used here.
  [
    "sendProposals((string,string,uint256,(address,uint256,bytes)[])[])",
  ],
  [
    ethers.utils.defaultAbiCoder.encode(
      [
        "(string destinationChain,string destinationContract,uint256 gas,(address target,uint256 value,bytes callData)[] calls)[]",
      ],
      [proposalExecutions]
    ),
  ],
  `A proposal to set "Hello World" message at Avalanche chain and Fantom chain`
);

This results in the proposal payload being submitted to the Governor contract, which triggers the subsequent stages of voting, queuing, and execution. This culminates in the invocation of the sendProposal or sendProposals function on the InterchainProposalSender contract on Ethereum, setting off the interchain method call.

Summary

The sample code snippet instructs the InterchainProposalSender contract on Ethereum to initiate an interchain method call via the Axelar Network. Specifically, the proposal aims to alter the DummyContract.sol on Avalanche, updating a string to "Hello World". Upon proposal creation, it follows the typical governance process.