Accounts: L1->L2 transactions
Accounts: L1->L2 transactions
This section explores the methods which allow the account classes to send transactions from L1 to L2.
If you want to get some background on how L1->L2 interaction works on zkSync, go through the introduction and the guide.
The zkSync Python SDK account is compatible with the eth_account package, and in most cases users can have their private key and get account instances by using it.
Example
from eth_account import Account
from eth_account.signers.local import LocalAccount
...
account: LocalAccount = Account.from_key("PRIVATE_KEY")
The base property that is used directly with account is: Account.address.
Finalizing deposit
Deposits are executed in 2 steps - initiated on L2 and finalized on L1, it returns the finalized deposit receipt.
def finalize_deposit(self, l1_sender: HexStr,l2_receiver: HexStr,l1_token: HexStr,amount: int, data: bytes) -> TxReceipt
Arguments
| Name | Description |
|---|---|
| l1_sender | The ERC20 sender address of the token to deposit. |
| l2_receiver | The address that will receive the deposited tokens on L2. |
| l1_token | The address of the deposited L1 ERC20 token. |
| amount | The amount of the token to be deposited. |
| data | Returns the transaction receipt of the transaction |
Example
def finalize_deposit(self,
l1_sender: HexStr,
l2_receiver: HexStr,
l1_token: HexStr,
amount: int,
data: bytes) -> TxReceipt:
tx = self.contract.functions.finalizeDeposit(l1_sender,
l2_receiver,
l1_token,
amount,
data).build_transaction(
{
"from": self.zksync_account.address,
"nonce": self._get_nonce(),
"gas": self.gas_provider.gas_limit(),
"gasPrice": self.gas_provider.gas_price()
})
signed_tx = self.zksync_account.sign_transaction(tx)
txn_hash = self.web3.zksync.send_raw_transaction(signed_tx.rawTransaction)
txn_receipt = self.web3.zksync.wait_for_transaction_receipt(txn_hash)
return txn_receipt
Claim Failed Deposit
The claimFailedDeposit method withdraws funds from the initiated deposit, which failed when finalizing on L2.
If the deposit L2 transaction has failed, it sends an L1 transaction calling claimFailedDeposit method of the L1 bridge, which results in returning L1 tokens back to the depositor, otherwise throws the error.
def claim_failed_deposit(self, deposit_sender: HexStr,
l1_token: HexStr,
l2tx_hash,
l2_block_number: int,
l2_msg_index: int,
merkle_proof: List[bytes]) -> TxReceipt
Arguments
| Name | Description |
|---|---|
| deposit_sender | The address of the deposit initiator. |
| l2tx_hash | The L2 transaction hash of the failed deposit finalization. |
| l1_token | The address of the deposited L1 ERC20 token. |
| l2_block_number | The L2 block number where the deposit finalization was processed. |
| l2_msg_index | The position in the L2 logs Merkle tree of the l2Log that was sent with the message. |
| merkle_proof | The Merkle proof of the processing L1 -> L2 transaction with deposit finalization |
Getting a nonce
The _get_nonce method which is an alias for getTransactionCount, it returns the number of transactions this account has ever sent.
def _get_nonce(self, account) -> transaction_count
Arguments
| Name | Description |
|---|---|
| account | The address of a user |
Deposit
Returns the transaction receipt of the deposit.
def deposit(self, l2_receiver: HexStr, l1_token: HexStr, amount: int) -> txn_receipt
Arguments
| Name | Description |
|---|---|
| l2_receiver | The address that will receive the deposited tokens on L2. |
| l1_token | The address of the deposited L1 ERC20 token. |
| amount | The amount of the token to be deposited. |
Example
def deposit(self, l2_receiver: HexStr, l1_token: HexStr, amount: int):
tx = self.contract.functions.deposit(l2_receiver,
l1_token,
amount).build_transaction(
{
"chainId": self.web3.eth.chain_id,
"from": self.account.address,
"nonce": self._get_nonce(),
"gas": self.gas_provider.gas_limit(),
"gasPrice": self.gas_provider.gas_price(),
"value": amount
})
signed_tx = self.account.sign_transaction(tx)
txn_hash = self.web3.eth.send_raw_transaction(signed_tx.rawTransaction)
txn_receipt = self.web3.eth.wait_for_transaction_receipt(txn_hash)
return txn_receipt
Finalizing withdrawals.
Withdrawals are executed in 2 steps - initiated on L2 and finalized on L1, this method returns the transaction receipt of the withdrawals.
def finalize_withdrawal(self,
l2_block_number: int,
l2_msg_index: int,
msg: bytes,
merkle_proof: List[bytes]) -> txn_receipt
Arguments
| Name | Description |
|---|---|
| l2_block_number | The L2 block number where the deposit finalization was processed. |
| l2_msg_index | The position in the L2 logs Merkle tree of the l2Log that was sent with the message. |
| l2_msg_index | The position in the L2 logs Merkle tree of the l2Log that was sent with the message. |
| merkle_proof | The Merkle proof of the processing L1 -> L2 transaction with deposit finalization |
Example
def finalize_withdrawal(self,
l2_block_number: int,
l2_msg_index: int,
msg: bytes,
merkle_proof: List[bytes]):
tx = self.contract.functions.finalizeWithdrawal(l2_block_number,
l2_msg_index,
msg,
merkle_proof).build_transaction(
{
"chainId": self.web3.eth.chain_id,
"from": self.account.address,
"nonce": self._get_nonce(),
"gas": self.gas_provider.gas_limit(),
"gasPrice": self.gas_provider.gas_price()
})
signed_tx = self.account.sign_transaction(tx)
txn_hash = self.web3.eth.send_raw_transaction(signed_tx.rawTransaction)
txn_receipt = self.web3.eth.wait_for_transaction_receipt(txn_hash)
return txn_receipt