# -*- coding: utf-8 -*-
from fractions import Fraction
from asyncinit import asyncinit
from ..exceptions import InvalidAssetException
from ..utils import assets_from_string, formatTimeString, parse_time
from ..price import Price as SyncPrice
@asyncinit
class Price(SyncPrice):
""" This class deals with all sorts of prices of any pair of assets to
simplify dealing with the tuple::
(quote, base)
each being an instance of :class:`.amount.Amount`. The
amount themselves define the price.
.. note::
The price (floating) is derived as ``base/quote``
:param list args: Allows to deal with different representations of a price
:param asset.Asset base: Base asset
:param asset.Asset quote: Quote asset
:param instance blockchain_instance: instance to use when accesing a RPC
:returns: All data required to represent a price
:rtype: dict
Way to obtain a proper instance:
* ``args`` is a str with a price and two assets
* ``args`` can be a floating number and ``base`` and ``quote`` being instances of :class:`.asset.Asset`
* ``args`` can be a floating number and ``base`` and ``quote`` being instances of ``str``
* ``args`` can be dict with keys ``price``, ``base``, and ``quote`` (*graphene balances*)
* ``args`` can be dict with keys ``base`` and ``quote``
* ``args`` can be dict with key ``receives`` (filled orders)
* ``args`` being a list of ``[quote, base]`` both being instances of :class:`.amount.Amount`
* ``args`` being a list of ``[quote, base]`` both being instances of ``str`` (``amount symbol``)
* ``base`` and ``quote`` being instances of :class:`.asset.Amount`
This allows instanciations like:
* ``Price("0.315 USD/BTS")``
* ``Price(0.315, base="USD", quote="BTS")``
* ``Price(0.315, base=self.asset_class("USD"), quote=self.asset_class("BTS"))``
* ``Price({"base": {"amount": 1, "asset_id": "1.3.0"}, "quote": {"amount": 10, "asset_id": "1.3.106"}})``
* ``Price({"receives": {"amount": 1, "asset_id": "1.3.0"}, "pays": {"amount": 10, "asset_id": "1.3.106"}}, base_asset=self.asset_class("1.3.0"))``
* ``Price(quote="10 GOLD", base="1 USD")``
* ``Price("10 GOLD", "1 USD")``
* ``Price(self.amount_class("10 GOLD"), self.amount_class("1 USD"))``
* ``Price(1.0, "USD/GOLD")``
Instances of this class can be used in regular mathematical expressions
(``+-*/%``) such as:
.. code-block:: python
>>> from price import Price
>>> Price("0.3314 USD/BTS") * 2
0.662600000 USD/BTS
"""
async def __init__(
self,
*args,
base=None,
quote=None,
base_asset=None, # to identify sell/buy
**kwargs
):
self.define_classes()
assert self.amount_class
assert self.asset_class
if len(args) == 1 and isinstance(args[0], str) and not base and not quote:
import re
price, assets = args[0].split(" ")
base_symbol, quote_symbol = assets_from_string(assets)
base = await self.asset_class(
base_symbol, blockchain_instance=self.blockchain
)
quote = await self.asset_class(
quote_symbol, blockchain_instance=self.blockchain
)
frac = Fraction(float(price)).limit_denominator(10 ** base["precision"])
self["quote"] = await self.amount_class(
amount=frac.denominator,
asset=quote,
blockchain_instance=self.blockchain,
)
self["base"] = await self.amount_class(
amount=frac.numerator, asset=base, blockchain_instance=self.blockchain
)
elif (
len(args) == 1
and isinstance(args[0], dict)
and "base" in args[0]
and "quote" in args[0]
):
assert "price" not in args[0], "You cannot provide a 'price' this way"
# Regular 'price' objects according to the backend
base_id = args[0]["base"]["asset_id"]
if args[0]["base"]["asset_id"] == base_id:
self["base"] = await self.amount_class(
args[0]["base"], blockchain_instance=self.blockchain
)
self["quote"] = await self.amount_class(
args[0]["quote"], blockchain_instance=self.blockchain
)
else:
self["quote"] = await self.amount_class(
args[0]["base"], blockchain_instance=self.blockchain
)
self["base"] = await self.amount_class(
args[0]["quote"], blockchain_instance=self.blockchain
)
elif len(args) == 1 and isinstance(args[0], dict) and "receives" in args[0]:
# Filled order
assert base_asset, "Need a 'base_asset' asset"
base_asset = await self.asset_class(
base_asset, blockchain_instance=self.blockchain
)
if args[0]["receives"]["asset_id"] == base_asset["id"]:
# If the seller received "base" in a quote_base market, than
# it has been a sell order of quote
self["base"] = await self.amount_class(
args[0]["receives"], blockchain_instance=self.blockchain
)
self["quote"] = await self.amount_class(
args[0]["pays"], blockchain_instance=self.blockchain
)
self["type"] = "sell"
else:
# buy order
self["base"] = await self.amount_class(
args[0]["pays"], blockchain_instance=self.blockchain
)
self["quote"] = await self.amount_class(
args[0]["receives"], blockchain_instance=self.blockchain
)
self["type"] = "buy"
elif len(args) == 1 and (
isinstance(base, self.asset_class) and isinstance(quote, self.asset_class)
):
price = args[0]
frac = Fraction(float(price)).limit_denominator(10 ** base["precision"])
self["quote"] = await self.amount_class(
amount=frac.denominator,
asset=quote,
blockchain_instance=self.blockchain,
)
self["base"] = await self.amount_class(
amount=frac.numerator, asset=base, blockchain_instance=self.blockchain
)
elif len(args) == 1 and (
isinstance(base, self.amount_class) and isinstance(quote, self.amount_class)
):
price = args[0]
self["quote"] = quote
self["base"] = base
elif len(args) == 1 and isinstance(base, str) and isinstance(quote, str):
price = args[0]
base = await self.asset_class(base, blockchain_instance=self.blockchain)
quote = await self.asset_class(quote, blockchain_instance=self.blockchain)
frac = Fraction(float(price)).limit_denominator(10 ** base["precision"])
self["quote"] = await self.amount_class(
amount=frac.denominator,
asset=quote,
blockchain_instance=self.blockchain,
)
self["base"] = await self.amount_class(
amount=frac.numerator, asset=base, blockchain_instance=self.blockchain
)
elif len(args) == 0 and isinstance(base, str) and isinstance(quote, str):
self["quote"] = await self.amount_class(
quote, blockchain_instance=self.blockchain
)
self["base"] = await self.amount_class(
base, blockchain_instance=self.blockchain
)
# len(args) > 1
elif len(args) == 2 and isinstance(args[0], str) and isinstance(args[1], str):
self["base"] = await self.amount_class(
args[1], blockchain_instance=self.blockchain
)
self["quote"] = await self.amount_class(
args[0], blockchain_instance=self.blockchain
)
elif (
len(args) == 2
and isinstance(args[0], self.amount_class)
and isinstance(args[1], self.amount_class)
):
self["quote"], self["base"] = args[0], args[1]
# len(args) == 0
elif isinstance(base, self.amount_class) and isinstance(
quote, self.amount_class
):
self["quote"] = quote
self["base"] = base
elif (
len(args) == 2
and (isinstance(args[0], float) or isinstance(args[0], int))
and isinstance(args[1], str)
):
import re
price = args[0]
base_symbol, quote_symbol = assets_from_string(args[1])
base = await self.asset_class(
base_symbol, blockchain_instance=self.blockchain
)
quote = await self.asset_class(
quote_symbol, blockchain_instance=self.blockchain
)
frac = Fraction(float(price)).limit_denominator(10 ** base["precision"])
self["quote"] = await self.amount_class(
amount=frac.denominator,
asset=quote,
blockchain_instance=self.blockchain,
)
self["base"] = await self.amount_class(
amount=frac.numerator, asset=base, blockchain_instance=self.blockchain
)
else:
raise ValueError("Couldn't parse 'Price'.")
def __mul__(self, other):
# TODO: refactor sync version to self.amount_class
raise NotImplementedError(
"Async version of Price does not support multiplication between Price instances"
)
def __div__(self, other):
raise NotImplementedError(
"Async version of Price does not support division between Price instances"
)
[docs] async def copy(self):
return await self.__class__(
base=await self["base"].copy(), quote=await self["quote"].copy()
)
[docs] async def as_base(self, base):
""" Returns the price instance so that the base asset is ``base``.
Note: This makes a copy of the object!
"""
if base == self["base"]["symbol"]:
return await self.copy()
elif base == self["quote"]["symbol"]:
c = await self.copy()
return await c.invert()
else:
raise InvalidAssetException
[docs] async def as_quote(self, quote):
""" Returns the price instance so that the quote asset is ``quote``.
Note: This makes a copy of the object!
"""
if quote == self["quote"]["symbol"]:
return await self.copy()
elif quote == self["base"]["symbol"]:
c = await self.copy()
return await c.invert()
else:
raise InvalidAssetException
[docs] async def invert(self):
""" Invert the price (e.g. go from ``USD/BTS`` into ``BTS/USD``)
"""
tmp = self["quote"]
self["quote"] = self["base"]
self["base"] = tmp
if "for_sale" in self and self["for_sale"]:
self["for_sale"] = await self.amount_class(
self["for_sale"]["amount"] * self["price"],
self["base"]["symbol"],
blockchain_instance=self.blockchain,
)
return self