stable/freqtrade/persistence.py
2018-03-03 09:33:54 +08:00

221 lines
7.4 KiB
Python

"""
This module contains the class to persist trades into SQLite
"""
import logging
from datetime import datetime
from decimal import Decimal, getcontext
from typing import Dict, Optional
import arrow
from sqlalchemy import (Boolean, Column, DateTime, Float, Integer, String,
create_engine)
from sqlalchemy.engine import Engine
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm.scoping import scoped_session
from sqlalchemy.orm.session import sessionmaker
from sqlalchemy.pool import StaticPool
logger = logging.getLogger(__name__)
_CONF = {}
_DECL_BASE = declarative_base()
def init(config: dict, engine: Optional[Engine] = None) -> None:
"""
Initializes this module with the given config,
registers all known command handlers
and starts polling for message updates
:param config: config to use
:param engine: database engine for sqlalchemy (Optional)
:return: None
"""
_CONF.update(config)
if not engine:
if _CONF.get('dry_run', False):
# the user wants dry run to use a DB
if _CONF.get('dry_run_db', False):
engine = create_engine('sqlite:///tradesv3.dry_run.sqlite')
# Otherwise dry run will store in memory
else:
engine = create_engine('sqlite://',
connect_args={'check_same_thread': False},
poolclass=StaticPool,
echo=False)
else:
engine = create_engine('sqlite:///tradesv3.sqlite')
session = scoped_session(sessionmaker(bind=engine, autoflush=True, autocommit=True))
Trade.session = session()
Trade.query = session.query_property()
_DECL_BASE.metadata.create_all(engine)
# Clean dry_run DB
if _CONF.get('dry_run', False) and _CONF.get('dry_run_db', False):
clean_dry_run_db()
def cleanup() -> None:
"""
Flushes all pending operations to disk.
:return: None
"""
Trade.session.flush()
def clean_dry_run_db() -> None:
"""
Remove open_order_id from a Dry_run DB
:return: None
"""
for trade in Trade.query.filter(Trade.open_order_id.isnot(None)).all():
# Check we are updating only a dry_run order not a prod one
if 'dry_run' in trade.open_order_id:
trade.open_order_id = None
class Trade(_DECL_BASE):
"""
Class used to define a trade structure
"""
__tablename__ = 'trades'
id = Column(Integer, primary_key=True)
exchange = Column(String, nullable=False)
pair = Column(String, nullable=False)
is_open = Column(Boolean, nullable=False, default=True)
fee = Column(Float, nullable=False, default=0.0)
open_rate = Column(Float)
close_rate = Column(Float)
close_profit = Column(Float)
stake_amount = Column(Float, nullable=False)
amount = Column(Float)
open_date = Column(DateTime, nullable=False, default=datetime.utcnow)
close_date = Column(DateTime)
open_order_id = Column(String)
def __repr__(self):
return 'Trade(id={}, pair={}, amount={:.8f}, open_rate={:.8f}, open_since={})'.format(
self.id,
self.pair,
self.amount,
self.open_rate,
arrow.get(self.open_date).humanize() if self.is_open else 'closed'
)
def update(self, order: Dict) -> None:
"""
Updates this entity with amount and actual open/close rates.
:param order: order retrieved by exchange.get_order()
:return: None
"""
# Ignore open and cancelled orders
if not order['closed'] or order['rate'] is None:
return
logger.info('Updating trade (id=%d) ...', self.id)
getcontext().prec = 8 # Bittrex do not go above 8 decimal
if order['type'] == 'LIMIT_BUY':
# Update open rate and actual amount
self.open_rate = Decimal(order['rate'])
self.amount = Decimal(order['amount'])
logger.info('LIMIT_BUY has been fulfilled for %s.', self)
self.open_order_id = None
elif order['type'] == 'LIMIT_SELL':
self.close(order['rate'])
else:
raise ValueError('Unknown order type: {}'.format(order['type']))
cleanup()
def close(self, rate: float) -> None:
"""
Sets close_rate to the given rate, calculates total profit
and marks trade as closed
"""
self.close_rate = Decimal(rate)
self.close_profit = self.calc_profit_percent()
self.close_date = datetime.utcnow()
self.is_open = False
self.open_order_id = None
logger.info(
'Marking %s as closed as the trade is fulfilled and found no open orders for it.',
self
)
def calc_open_trade_price(
self,
fee: Optional[float] = None) -> float:
"""
Calculate the open_rate in BTC
:param fee: fee to use on the open rate (optional).
If rate is not set self.fee will be used
:return: Price in BTC of the open trade
"""
getcontext().prec = 8
buy_trade = (Decimal(self.amount) * Decimal(self.open_rate))
fees = buy_trade * Decimal(fee or self.fee)
return float(buy_trade + fees)
def calc_close_trade_price(
self,
rate: Optional[float] = None,
fee: Optional[float] = None) -> float:
"""
Calculate the close_rate in BTC
:param fee: fee to use on the close rate (optional).
If rate is not set self.fee will be used
:param rate: rate to compare with (optional).
If rate is not set self.close_rate will be used
:return: Price in BTC of the open trade
"""
getcontext().prec = 8
if rate is None and not self.close_rate:
return 0.0
sell_trade = (Decimal(self.amount) * Decimal(rate or self.close_rate))
fees = sell_trade * Decimal(fee or self.fee)
return float(sell_trade - fees)
def calc_profit(
self,
rate: Optional[float] = None,
fee: Optional[float] = None) -> float:
"""
Calculate the profit in BTC between Close and Open trade
:param fee: fee to use on the close rate (optional).
If rate is not set self.fee will be used
:param rate: close rate to compare with (optional).
If rate is not set self.close_rate will be used
:return: profit in BTC as float
"""
open_trade_price = self.calc_open_trade_price()
close_trade_price = self.calc_close_trade_price(
rate=Decimal(rate or self.close_rate),
fee=Decimal(fee or self.fee)
)
return float("{0:.8f}".format(close_trade_price - open_trade_price))
def calc_profit_percent(
self,
rate: Optional[float] = None,
fee: Optional[float] = None) -> float:
"""
Calculates the profit in percentage (including fee).
:param rate: rate to compare with (optional).
If rate is not set self.close_rate will be used
:return: profit in percentage as float
"""
getcontext().prec = 8
open_trade_price = self.calc_open_trade_price()
close_trade_price = self.calc_close_trade_price(
rate=Decimal(rate or self.close_rate),
fee=Decimal(fee or self.fee)
)
return float("{0:.8f}".format((close_trade_price / open_trade_price) - 1))