stable/freqtrade/strategy/strategy_wrapper.py
Matthias ae0e72a945 Provide strategy with copied objects
avoids accidental modification of crucial elements in a trade object
part of #5828
2021-11-08 19:59:29 +01:00

41 lines
1.4 KiB
Python

import logging
from copy import deepcopy
from freqtrade.exceptions import StrategyError
logger = logging.getLogger(__name__)
def strategy_safe_wrapper(f, message: str = "", default_retval=None, supress_error=False):
"""
Wrapper around user-provided methods and functions.
Caches all exceptions and returns either the default_retval (if it's not None) or raises
a StrategyError exception, which then needs to be handled by the calling method.
"""
def wrapper(*args, **kwargs):
try:
if 'trade' in kwargs:
# Protect accidental modifications from within the strategy
kwargs['trade'] = deepcopy(kwargs['trade'])
return f(*args, **kwargs)
except ValueError as error:
logger.warning(
f"{message}"
f"Strategy caused the following exception: {error}"
f"{f}"
)
if default_retval is None and not supress_error:
raise StrategyError(str(error)) from error
return default_retval
except Exception as error:
logger.exception(
f"{message}"
f"Unexpected error {error} calling {f}"
)
if default_retval is None and not supress_error:
raise StrategyError(str(error)) from error
return default_retval
return wrapper