scroll/contracts/docs/apis/L1WETHGateway.md

L1WETHGateway

L1WETHGateway

The L1WETHGateway contract is used to deposit WETH token on layer 1 and finalize withdraw WETH from layer 2.

The deposited WETH tokens are not held in the gateway. It will first be unwrapped as Ether and then the Ether will be sent to the L1ScrollMessenger contract. On finalizing withdraw, the Ether will be transferred from L1ScrollMessenger, then wrapped as WETH and finally transfer to recipient.

Methods

WETH

function WETH() external view returns (address)

The address of L1 WETH address.

Returns

Name	Type	Description
_0	address	undefined

counterpart

function counterpart() external view returns (address)

The address of corresponding L1/L2 Gateway contract.

Returns

Name	Type	Description
_0	address	undefined

depositERC20

function depositERC20(address _token, uint256 _amount, uint256 _gasLimit) external payable

Deposit some token to a caller's account on L2.

Make this function payable to send relayer fee in Ether.

Parameters

Name	Type	Description
_token	address	The address of token in L1.
_amount	uint256	The amount of token to transfer.
_gasLimit	uint256	Gas limit required to complete the deposit on L2.

depositERC20

function depositERC20(address _token, address _to, uint256 _amount, uint256 _gasLimit) external payable

Deposit some token to a recipient's account on L2.

Make this function payable to send relayer fee in Ether.

Parameters

Name	Type	Description
_token	address	The address of token in L1.
_to	address	The address of recipient's account on L2.
_amount	uint256	The amount of token to transfer.
_gasLimit	uint256	Gas limit required to complete the deposit on L2.

depositERC20AndCall

function depositERC20AndCall(address _token, address _to, uint256 _amount, bytes _data, uint256 _gasLimit) external payable

Deposit some token to a recipient's account on L2 and call.

Make this function payable to send relayer fee in Ether.

Parameters

Name	Type	Description
_token	address	The address of token in L1.
_to	address	The address of recipient's account on L2.
_amount	uint256	The amount of token to transfer.
_data	bytes	Optional data to forward to recipient's account.
_gasLimit	uint256	Gas limit required to complete the deposit on L2.

finalizeWithdrawERC20

function finalizeWithdrawERC20(address _l1Token, address _l2Token, address _from, address _to, uint256 _amount, bytes _data) external payable

Complete ERC20 withdraw from L2 to L1 and send fund to recipient's account in L1.

Make this function payable to handle WETH deposit/withdraw. The function should only be called by L1ScrollMessenger. The function should also only be called by L2ERC20Gateway in L2.

Parameters

Name	Type	Description
_l1Token	address	The address of corresponding L1 token.
_l2Token	address	The address of corresponding L2 token.
_from	address	The address of account who withdraw the token in L2.
_to	address	The address of recipient in L1 to receive the token.
_amount	uint256	The amount of the token to withdraw.
_data	bytes	Optional data to forward to recipient's account.

getL2ERC20Address

function getL2ERC20Address(address) external view returns (address)

Return the corresponding l2 token address given l1 token address.

Parameters

Name	Type	Description
_0	address	undefined

Returns

Name	Type	Description
_0	address	undefined

initialize

function initialize(address _counterpart, address _router, address _messenger) external nonpayable

Initialize the storage of L1WETHGateway.

The parameters _counterpart, _router and _messenger are no longer used.

Parameters

Name	Type	Description
_counterpart	address	The address of L2ETHGateway in L2.
_router	address	The address of L1GatewayRouter in L1.
_messenger	address	The address of L1ScrollMessenger in L1.

l2WETH

function l2WETH() external view returns (address)

The address of L2 WETH address.

Returns

Name	Type	Description
_0	address	undefined

messenger

function messenger() external view returns (address)

The address of corresponding L1ScrollMessenger/L2ScrollMessenger contract.

Returns

Name	Type	Description
_0	address	undefined

onDropMessage

function onDropMessage(bytes _message) external payable

Parameters

Name	Type	Description
_message	bytes	undefined

owner

function owner() external view returns (address)

Returns the address of the current owner.

Returns

Name	Type	Description
_0	address	undefined

renounceOwnership

function renounceOwnership() external nonpayable

Leaves the contract without owner. It will not be possible to call onlyOwner functions. Can only be called by the current owner. NOTE: Renouncing ownership will leave the contract without an owner, thereby disabling any functionality that is only available to the owner.

router

function router() external view returns (address)

The address of L1GatewayRouter/L2GatewayRouter contract.

Returns

Name	Type	Description
_0	address	undefined

transferOwnership

function transferOwnership(address newOwner) external nonpayable

Transfers ownership of the contract to a new account (newOwner). Can only be called by the current owner.

Parameters

Name	Type	Description
newOwner	address	undefined

Events

DepositERC20

event DepositERC20(address indexed l1Token, address indexed l2Token, address indexed from, address to, uint256 amount, bytes data)

Emitted when someone deposit ERC20 token from L1 to L2.

Parameters

Name	Type	Description
l1Token indexed	address	The address of the token in L1.
l2Token indexed	address	The address of the token in L2.
from indexed	address	The address of sender in L1.
to	address	The address of recipient in L2.
amount	uint256	The amount of token will be deposited from L1 to L2.
data	bytes	The optional calldata passed to recipient in L2.

FinalizeWithdrawERC20

event FinalizeWithdrawERC20(address indexed l1Token, address indexed l2Token, address indexed from, address to, uint256 amount, bytes data)

Emitted when ERC20 token is withdrawn from L2 to L1 and transfer to recipient.

Parameters

Name	Type	Description
l1Token indexed	address	The address of the token in L1.
l2Token indexed	address	The address of the token in L2.
from indexed	address	The address of sender in L2.
to	address	The address of recipient in L1.
amount	uint256	The amount of token withdrawn from L2 to L1.
data	bytes	The optional calldata passed to recipient in L1.

Initialized

event Initialized(uint8 version)

Triggered when the contract has been initialized or reinitialized.

Parameters

Name	Type	Description
version	uint8	undefined

OwnershipTransferred

event OwnershipTransferred(address indexed previousOwner, address indexed newOwner)

Parameters

Name	Type	Description
previousOwner indexed	address	undefined
newOwner indexed	address	undefined

RefundERC20

event RefundERC20(address indexed token, address indexed recipient, uint256 amount)

Emitted when some ERC20 token is refunded.

Parameters

Name	Type	Description
token indexed	address	The address of the token in L1.
recipient indexed	address	The address of receiver in L1.
amount	uint256	The amount of token refunded to receiver.

Errors

ErrorCallerIsNotCounterpartGateway

error ErrorCallerIsNotCounterpartGateway()

Thrown when the cross chain sender is not the counterpart gateway contract.

ErrorCallerIsNotMessenger

error ErrorCallerIsNotMessenger()

Thrown when the caller is not corresponding L1ScrollMessenger or L2ScrollMessenger.

ErrorNotInDropMessageContext

error ErrorNotInDropMessageContext()

Thrown when ScrollMessenger is not dropping message.

ErrorZeroAddress

error ErrorZeroAddress()

Thrown when the given address is address(0).