ethers-opt/src/op.ts

Collection of heavily optimized functions for ethers.js V6

import { Transaction, TransactionRequest, parseUnits, parseEther, ZeroAddress } from 'ethers';
import { OpGasPriceOracle } from './typechain/index.js';

/**
 * Address of the OP Stack L1 Gas Price Oracle on standard OP chains.
 */
export const GAS_PRICE_ORACLE_ADDRESS = '0x420000000000000000000000000000000000000F';

/**
 * Calculate the L1 data/fee for an OP Stack transaction, using the onchain oracle contract.
 * @param oracle Instance of OpGasPriceOracle contract.
 * @param tx Optional: TransactionRequest to calculate the L1 fee for.
 * @returns Promise resolving to the L1 fee as a bigint.
 */
export async function getL1Fee(oracle: OpGasPriceOracle, tx?: TransactionRequest): Promise<bigint> {
    const { unsignedSerialized } = Transaction.from({
        chainId: tx?.chainId || 10000n,
        data: tx?.data || '0x',
        gasLimit: tx?.gasLimit || 10_000_000,
        gasPrice: tx?.gasPrice || parseUnits('10000', 'gwei'),
        nonce: tx?.nonce || 100_000,
        to: tx?.to instanceof Promise ? ((await tx?.to) as string) : (tx?.to as string) || ZeroAddress,
        type: tx?.type || 0,
        value: tx?.value || parseEther('10000'),
    });

    return ((await oracle.getL1Fee(unsignedSerialized)) * 13n) / 10n;
}