from decimal import Decimal
from typing import Union
from .operation import Operation
from .utils import check_price, check_amount
from ..asset import Asset
from ..price import Price
from ..xdr import Xdr
[docs]class ManageBuyOffer(Operation):
"""The :class:`ManageBuyOffer` object, which represents a ManageBuyOffer
operation on Stellar's network.
Creates, updates, or deletes an buy offer.
If you want to create a new offer set Offer ID to 0.
If you want to update an existing offer set Offer ID to existing offer ID.
If you want to delete an existing offer set Offer ID to existing offer ID
and set Amount to 0.
Threshold: Medium
:param selling: What you're selling.
:param buying: What you're buying.
:param amount: Amount being bought. if set to 0, delete the offer.
:param price: Price of thing being bought in terms of what you are selling.
:param offer_id: If `0`, will create a new offer (default). Otherwise,
edits an existing offer.
:param source: The source account (defaults to transaction source).
"""
def __init__(
self,
selling: Asset,
buying: Asset,
amount: Union[str, Decimal],
price: Union[Price, str, Decimal],
offer_id: int = 0,
source: str = None,
) -> None:
super().__init__(source)
check_amount(amount)
check_price(price)
self.selling: Asset = selling
self.buying: Asset = buying
self.amount: Union[str, Decimal] = amount
self.price: Union[Price, str, Decimal] = price
self.offer_id: int = offer_id
@classmethod
def type_code(cls) -> int:
return Xdr.const.MANAGE_BUY_OFFER
def _to_operation_body(self) -> Xdr.nullclass:
selling = self.selling.to_xdr_object()
buying = self.buying.to_xdr_object()
if isinstance(self.price, Price):
price_fraction = self.price
else:
price_fraction = Price.from_raw_price(self.price)
price = price_fraction.to_xdr_object()
amount = Operation.to_xdr_amount(self.amount)
manage_buy_offer_op = Xdr.types.ManageBuyOfferOp(
selling, buying, amount, price, self.offer_id
)
body = Xdr.nullclass()
body.type = Xdr.const.MANAGE_BUY_OFFER
body.manageBuyOfferOp = manage_buy_offer_op
return body
[docs] @classmethod
def from_xdr_object(
cls, operation_xdr_object: Xdr.types.Operation
) -> "ManageBuyOffer":
"""Creates a :class:`ManageBuyOffer` object from an XDR Operation object.
"""
source = Operation.get_source_from_xdr_obj(operation_xdr_object)
selling = Asset.from_xdr_object(
operation_xdr_object.body.manageBuyOfferOp.selling
)
buying = Asset.from_xdr_object(
operation_xdr_object.body.manageBuyOfferOp.buying
)
amount = Operation.from_xdr_amount(
operation_xdr_object.body.manageBuyOfferOp.buyAmount
)
price = Price.from_xdr_object(operation_xdr_object.body.manageBuyOfferOp.price)
offer_id = operation_xdr_object.body.manageBuyOfferOp.offerID
op = cls(
source=source,
selling=selling,
buying=buying,
amount=amount,
price=price,
offer_id=offer_id,
)
op._source_muxed = Operation.get_source_muxed_from_xdr_obj(operation_xdr_object)
return op