시스템 모듈 사용

// SAFE: the precompile address is fixed on Stable.
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.24;
 
struct Coin {
    string denom;
    uint256 amount;
}
 
interface IStaking {
    function delegate(
        address delegatorAddress,
        address validatorAddress,
        uint256 amount
    ) external returns (bool success);
 
    function delegation(
        address delegatorAddress,
        address validatorAddress
    ) external view returns (uint256 shares, Coin memory balance);
}
 
contract StakingHelper {
    address constant STAKING_PRECOMPILE =
        0x0000000000000000000000000000000000000800;
 
    /// @notice Delegate STABLE tokens to a validator from this contract.
    function delegateToValidator(
        address validatorAddress,
        uint256 amount
    ) external returns (bool) {
        return IStaking(STAKING_PRECOMPILE).delegate(
            address(this),
            validatorAddress,
            amount
        );
    }
 
    /// @notice Read the current delegation of this contract to a validator.
    function myDelegation(address validatorAddress)
        external
        view
        returns (uint256 shares, Coin memory balance)
    {
        return IStaking(STAKING_PRECOMPILE).delegation(
            address(this),
            validatorAddress
        );
    }
}

// queryDelegation.ts
import { ethers } from "ethers";
import "dotenv/config";
 
const provider = new ethers.JsonRpcProvider("https://rpc.testnet.stable.xyz");
 
const STAKING_PRECOMPILE = "0x0000000000000000000000000000000000000800";
 
const staking = new ethers.Contract(
  STAKING_PRECOMPILE,
  [
    "function delegation(address delegator, address validator) view returns (uint256 shares, (string denom, uint256 amount) balance)",
  ],
  provider
);
 
const delegator = "0x1111111111111111111111111111111111111111";
const validator = "0x2222222222222222222222222222222222222222";
 
const [shares, balance] = await staking.delegation(delegator, validator);
console.log("Delegation shares: ", shares.toString());
console.log("Delegation denomination:", balance.denom);
console.log("Delegation amount:", balance.amount.toString());

npx tsx queryDelegation.ts

Delegation shares:  <share amount>
Delegation denomination: <staking denomination>
Delegation amount: <base-unit amount>

// watchUnbonding.ts
import { ethers } from "ethers";
 
const provider = new ethers.JsonRpcProvider("https://rpc.testnet.stable.xyz");
 
const STABLE_SYSTEM = "0x0000000000000000000000000000000000009999";
 
const stableSystem = new ethers.Contract(
  STABLE_SYSTEM,
  [
    "event UnbondingCompleted(address indexed delegator, address indexed validator, uint64 indexed originBlockHeight, uint256 amount)",
  ],
  provider
);
 
stableSystem.on("UnbondingCompleted", (delegator, validator, originBlockHeight, amount, event) => {
  console.log("Unbonding completed for:", delegator);
  console.log("Origin block:", originBlockHeight.toString());
  console.log("Amount:", ethers.formatEther(amount), "STABLE");
  console.log("Tx:", event.log.transactionHash);
});
 
console.log("Listening for UnbondingCompleted events...");

npx tsx watchUnbonding.ts

Listening for UnbondingCompleted events...
Unbonding completed for: 0xabcd...
Origin block: 36975999
Amount: 100.0 STABLE
Tx: 0x12ab...