How to use the @eth-optimism/contracts.getContractInterface function in @eth-optimism/contracts

private async _getLastTimestampAndBlockNumber(): Promise<{
    lastTimestamp: number
    lastBlockNumber: number
  }> {
    const manager = new Contract(
      this.addressManagerAddress,
      getNewContractInterface('Lib_AddressManager'),
      this.signer.provider
    )

    const addr = await manager.getAddress(
      'OVM_ChainStorageContainer:CTC:batches'
    )
    const container = new Contract(
      addr,
      getNewContractInterface('iOVM_ChainStorageContainer'),
      this.signer.provider
    )

    let meta = await container.getGlobalMetadata()
    // remove 0x
    meta = meta.slice(2)
    // convert to bytes27

private async _getLastTimestampAndBlockNumber(): Promise<{
    lastTimestamp: number
    lastBlockNumber: number
  }> {
    const manager = new Contract(
      this.addressManagerAddress,
      getNewContractInterface('Lib_AddressManager'),
      this.signer.provider
    )

    const addr = await manager.getAddress(
      'OVM_ChainStorageContainer:CTC:batches'
    )
    const container = new Contract(
      addr,
      getNewContractInterface('iOVM_ChainStorageContainer'),
      this.signer.provider
    )

    let meta = await container.getGlobalMetadata()
    // remove 0x
    meta = meta.slice(2)
    // convert to bytes27
    meta = meta.slice(10)

    const totalElements = meta.slice(-10)
    const nextQueueIndex = meta.slice(-20, -10)
    const lastTimestamp = parseInt(meta.slice(-30, -20), 16)
    const lastBlockNumber = parseInt(meta.slice(-40, -30), 16)
    this.logger.debug('Retrieved timestamp and block number from CTC', {
      lastTimestamp,
      lastBlockNumber,

export const getMessagesByTransactionHash = async (
  l2RpcProvider: ethers.providers.JsonRpcProvider,
  l2CrossDomainMessengerAddress: string,
  l2TransactionHash: string
): Promise => {
  // Complain if we can't find the given transaction.
  const transaction = await l2RpcProvider.getTransaction(l2TransactionHash)
  if (transaction === null) {
    throw new Error(`unable to find tx with hash: ${l2TransactionHash}`)
  }

  const l2CrossDomainMessenger = new ethers.Contract(
    l2CrossDomainMessengerAddress,
    getContractInterface('OVM_L2CrossDomainMessenger'),
    l2RpcProvider
  )

  // Find all SentMessage events created in the same block as the given transaction. This is
  // reliable because we should only have one transaction per block.
  const sentMessageEvents = await l2CrossDomainMessenger.queryFilter(
    l2CrossDomainMessenger.filters.SentMessage(),
    transaction.blockNumber,
    transaction.blockNumber
  )

  // Decode the messages and turn them into a nicer struct.
  const sentMessages = sentMessageEvents.map((sentMessageEvent) => {
    const encodedMessage = sentMessageEvent.args.message
    const decodedMessage = l2CrossDomainMessenger.interface.decodeFunctionData(
      'relayMessage',

export const loadContract = (
  name: string,
  address: string,
  provider: JsonRpcProvider
): Contract => {
  return new Contract(address, getContractInterface(name) as any, provider)
}

export const getStateBatchAppendedEventByTransactionIndex = async (
  l1RpcProvider: ethers.providers.JsonRpcProvider,
  l1StateCommitmentChainAddress: string,
  l2TransactionIndex: number
): Promise => {
  const l1StateCommitmentChain = new ethers.Contract(
    l1StateCommitmentChainAddress,
    getContractInterface('OVM_StateCommitmentChain'),
    l1RpcProvider
  )

  const getStateBatchAppendedEventByBatchIndex = async (
    index: number
  ): Promise => {
    const eventQueryResult = await l1StateCommitmentChain.queryFilter(
      l1StateCommitmentChain.filters.StateBatchAppended(index)
    )
    if (eventQueryResult.length === 0) {
      return null
    } else {
      return eventQueryResult[0]
    }
  }

const encodeCrossDomainMessage = (message: CrossDomainMessage): string => {
  return getContractInterface(
    'OVM_L2CrossDomainMessenger'
  ).encodeFunctionData('relayMessage', [
    message.target,
    message.sender,
    message.message,
    message.messageNonce,
  ])
}