from typing import Union, Optional
from .exceptions import ValueError
from .keypair import Keypair
from .transaction import Transaction
from .transaction_envelope import TransactionEnvelope
from .utils import parse_ed25519_account_id_from_muxed_account_xdr_object
from .xdr import Xdr
BASE_FEE = 100
__all__ = ["FeeBumpTransaction"]
[docs]class FeeBumpTransaction:
"""The :class:`FeeBumpTransaction` object, which represents a fee bump transaction
on Stellar's network.
See `CAP-0015 <https://github.com/stellar/stellar-protocol/blob/master/core/cap-0015.md>`_ for more information.
:param fee_source: The account paying for the transaction.
:param base_fee: The max fee willing to pay per operation in inner transaction (**in stroops**).
:param inner_transaction_envelope: The TransactionEnvelope to be bumped by the fee bump transaction.
"""
def __init__(
self,
fee_source: Union[Keypair, str],
base_fee: int,
inner_transaction_envelope: TransactionEnvelope,
) -> None:
if not isinstance(inner_transaction_envelope.transaction, Transaction):
raise ValueError(
"Invalid `inner_transaction`, it should be `stellar_sdk.transaction.Transaction`."
)
if isinstance(fee_source, str):
fee_source = Keypair.from_public_key(fee_source)
self._fee_source: Keypair = fee_source
self._fee_source_muxed: Optional[Xdr.types.MuxedAccount] = None
self.base_fee = base_fee
self.inner_transaction_envelope = (
inner_transaction_envelope.to_transaction_envelope_v1()
)
self._inner_transaction = self.inner_transaction_envelope.transaction
inner_operations_length = len(self._inner_transaction.operations)
inner_base_fee_rate = self._inner_transaction.fee / inner_operations_length
if self.base_fee < inner_base_fee_rate or self.base_fee < BASE_FEE:
raise ValueError(
f"Invalid `base_fee`, it should be at least {self._inner_transaction.fee if self._inner_transaction.fee > BASE_FEE else BASE_FEE} stroops."
)
@property
def fee_source(self) -> Keypair:
return self._fee_source
@fee_source.setter
def fee_source(self, value: Union[Keypair, str]):
if isinstance(value, str):
value = Keypair.from_public_key(value)
self._fee_source: Keypair = value
self._fee_source_muxed: Optional[Xdr.types.MuxedAccount] = None
[docs] def to_xdr_object(self) -> Xdr.types.FeeBumpTransaction:
"""Get an XDR object representation of this :class:`FeeBumpTransaction`.
:return: XDR Transaction object
"""
if self._fee_source_muxed is not None:
fee_source = self._fee_source_muxed
else:
fee_source = self._fee_source.xdr_muxed_account()
fee = self.base_fee * (len(self._inner_transaction.operations) + 1)
ext = Xdr.nullclass()
ext.v = 0
return Xdr.types.FeeBumpTransaction(
feeSource=fee_source,
fee=fee,
innerTx=self.inner_transaction_envelope.to_xdr_object(),
ext=ext,
)
[docs] @classmethod
def from_xdr_object(
cls, tx_xdr_object: Xdr.types.FeeBumpTransaction, network_passphrase: str
) -> "FeeBumpTransaction":
"""Create a new :class:`FeeBumpTransaction` from an XDR object.
:param tx_xdr_object: The XDR object that represents a fee bump transaction.
:param network_passphrase: The network to connect to for verifying and retrieving additional attributes from.
:return: A new :class:`FeeBumpTransaction` object from the given XDR Transaction object.
"""
source = parse_ed25519_account_id_from_muxed_account_xdr_object(
tx_xdr_object.feeSource
)
inner_transaction_envelope = TransactionEnvelope.from_xdr_object(
tx_xdr_object.innerTx, network_passphrase
)
inner_transaction_operation_length = len(
inner_transaction_envelope.transaction.operations
)
base_fee = int(tx_xdr_object.fee / (inner_transaction_operation_length + 1))
tx = cls(
fee_source=source,
base_fee=base_fee,
inner_transaction_envelope=inner_transaction_envelope,
)
tx._fee_source_muxed = tx_xdr_object.feeSource
return tx
[docs] @classmethod
def from_xdr(cls, xdr: str, network_passphrase: str) -> "FeeBumpTransaction":
"""Create a new :class:`FeeBumpTransaction` from an XDR string.
:param xdr: The XDR string that represents a transaction.
:param network_passphrase: The network to connect to for verifying and retrieving additional attributes from.
:return: A new :class:`FeeBumpTransaction` object from the given XDR FeeBumpTransaction base64 string object.
"""
xdr_object = Xdr.types.FeeBumpTransaction.from_xdr(xdr)
return cls.from_xdr_object(xdr_object, network_passphrase)