@eth-optimism/watcher

@eth-optimism/watcher

Watcher

Our Watcher allows you to retrieve all transaction hashes related to cross domain messages such as deposits and withdrawals.

In order to use, first send a transaction which sends a cross domain message, for example a deposit from L1 into L2. After sending the deposit transaction and storing the transaction hash, use getMessageHashesFromL1Tx(l1TxHash) to get an array of the message hashes of all of the L1->L2 messages that were sent inside of that L1 tx (This will usually just be a single element array, but it can return multiple if one L1 transaction triggers multiple deposits). getMessageHashesFromL2Tx(l2TxHash) does the same for L2->L1 messages.

getL2TransactionReceipt(messageHash) takes in an L1->L2 message hash and then after 2-5 minutes, returns the receipt of the L2 tx that the message ends up getting relayed in. getL1TransactionReceipt(messageHash) does the same for L2->L1 messages, except the delay is 7 days. There is an optional parameter pollForPending on getL1TransactionReceipt and getL2TransactionReceipt that is set to true by default. If you would like to disable polling and rather just search if the message has already been relayed or return undefined otherwise, then you can use getL1TransactionReceipt(messageHash, false).

import { Watcher } from '@eth-optimism/watcher/'
import { JsonRpcProvider } from 'ethers/providers'

const watcher = new Watcher({
  l1: {
    provider: new JsonRpcProvider('INFURA_L1_URL'),
    messengerAddress: '0x...'
  },
  l2: {
    provider: new JsonRpcProvider('OPTIMISM_L2_URL'),
    messengerAddress: '0x...'
  }
})
const l1TxHash = (await depositContract.deposit(100)).hash
const [messageHash] = await watcher.getMessageHashesFromL1Tx(l1TxHash)
console.log('L1->L2 message hash:', messageHash)
const l2TxReceipt = await watcher.getL2TransactionReceipt(messageHash)