Paymaster Utilities

The paymaster utilities library contains essential utilities for using paymasters on zkSync Era.

Contract interfaces

PaymasterFlowEncoder

Constant ABI definition for the Paymaster Flow Interface.

encoder = PaymasterFlowEncoder(zk_web3)

Functions

encodeApprovalBased

Returns encoded input for an approval-based paymaster.

Inputs

Parameter	Type	Description
address	HexStr	The token address of the paymaster.
min_allowance	int	The minimal amount of token that can be used to pay fee.
inner_input	bytes	The input data to the paymaster.

paymaster_params = PaymasterParams(**{
    "paymaster": paymaster_address,
    "paymaster_input": zk_web3.to_bytes(
        hexstr=PaymasterFlowEncoder(zk_web3).encode_approval_based(token_address, 1, b''))
})

encode_general

As above but for general-based paymaster.

Inputs

Parameter	Type	Description
inputs	bytes	The input data to the paymaster.

paymaster_params = PaymasterParams(**{
    "paymaster": paymaster_address,
    "paymaster_input": zk_web3.to_bytes(
        hexstr=PaymasterFlowEncoder(zk_web3).encode_general( b''))
})

Find out more about the PaymasterParams type. Check out the example how to use paymaster.