Source code for stellar_sdk.xdr.utils

from decimal import Decimal, Context, Inexact
from typing import Union

_ONE = Decimal(10 ** 7)

[docs]def to_xdr_amount(value: Union[str, Decimal]) -> int: """Converts an amount to the appropriate value to send over the network as a part of an XDR object. Each asset amount is encoded as a signed 64-bit integer in the XDR structures. An asset amount unit (that which is seen by end users) is scaled down by a factor of ten million (10,000,000) to arrive at the native 64-bit integer representation. For example, the integer amount value 25,123,456 equals 2.5123456 units of the asset. This scaling allows for seven decimal places of precision in human-friendly amount units. This static method correctly multiplies the value by the scaling factor in order to come to the integer value used in XDR structures. See `Stellar's documentation on Asset Precision <>`_ for more information. :param value: The amount to convert to an integer for XDR serialization. """ if not (isinstance(value, str) or isinstance(value, Decimal)): raise TypeError( f"Value of type '{value}' must be of type {str} or {Decimal}, but got {type(value)}." ) # throw exception if value * ONE has decimal places (it can't be represented as int64) try: amount = int( (Decimal(value) * _ONE).to_integral_exact(context=Context(traps=[Inexact])) ) except Inexact: raise ValueError( f"Value of '{value}' must have at most 7 digits after the decimal." ) if amount < 0 or amount > 9223372036854775807: raise ValueError( f"Value of '{value}' must represent a positive number " "and the max valid value is 922337203685.4775807." ) return amount
[docs]def from_xdr_amount(value: int) -> str: """Converts an str amount from an XDR amount object :param value: The amount to convert to a string from an XDR int64 amount. """ return str(Decimal(value) / _ONE)