stable/freqtrade/pairlist/pairlistmanager.py
2020-05-19 03:56:31 +03:00

118 lines
4.0 KiB
Python

"""
PairList manager class
"""
import logging
from copy import deepcopy
from typing import Dict, List
from cachetools import TTLCache, cached
from freqtrade.exceptions import OperationalException
from freqtrade.pairlist.IPairList import IPairList
from freqtrade.resolvers import PairListResolver
from freqtrade.typing import ListPairsWithTimeframes
logger = logging.getLogger(__name__)
class PairListManager():
def __init__(self, exchange, config: dict) -> None:
self._exchange = exchange
self._config = config
self._whitelist = self._config['exchange'].get('pair_whitelist')
self._blacklist = self._config['exchange'].get('pair_blacklist', [])
self._pairlist_handlers: List[IPairList] = []
self._tickers_needed = False
for pairlist_handler_config in self._config.get('pairlists', None):
if 'method' not in pairlist_handler_config:
logger.warning(f"No method found in {pairlist_handler_config}, ignoring.")
continue
pairlist_handler = PairListResolver.load_pairlist(
pairlist_handler_config['method'],
exchange=exchange,
pairlistmanager=self,
config=config,
pairlistconfig=pairlist_handler_config,
pairlist_pos=len(self._pairlist_handlers)
)
self._tickers_needed |= pairlist_handler.needstickers
self._pairlist_handlers.append(pairlist_handler)
if not self._pairlist_handlers:
raise OperationalException("No Pairlist Handlers defined")
@property
def whitelist(self) -> List[str]:
"""
Has the current whitelist
"""
return self._whitelist
@property
def blacklist(self) -> List[str]:
"""
Has the current blacklist
-> no need to overwrite in subclasses
"""
return self._blacklist
@property
def name_list(self) -> List[str]:
"""
Get list of loaded Pairlist Handler names
"""
return [p.name for p in self._pairlist_handlers]
def short_desc(self) -> List[Dict]:
"""
List of short_desc for each Pairlist Handler
"""
return [{p.name: p.short_desc()} for p in self._pairlist_handlers]
@cached(TTLCache(maxsize=1, ttl=1800))
def _get_cached_tickers(self):
return self._exchange.get_tickers()
def refresh_pairlist(self) -> None:
"""
Run pairlist through all configured Pairlist Handlers.
"""
# Tickers should be cached to avoid calling the exchange on each call.
tickers: Dict = {}
if self._tickers_needed:
tickers = self._get_cached_tickers()
# Adjust whitelist if filters are using tickers
pairlist = self._prepare_whitelist(self._whitelist.copy(), tickers)
# Process all Pairlist Handlers in the chain
for pairlist_handler in self._pairlist_handlers:
pairlist = pairlist_handler.filter_pairlist(pairlist, tickers)
# Validation against blacklist happens after the chain of Pairlist Handlers
# to ensure blacklist is respected.
pairlist = IPairList.verify_blacklist(pairlist, self.blacklist, True)
self._whitelist = pairlist
def _prepare_whitelist(self, pairlist: List[str], tickers) -> List[str]:
"""
Prepare sanitized pairlist for Pairlist Handlers that use tickers data - remove
pairs that do not have ticker available
"""
if self._tickers_needed:
# Copy list since we're modifying this list
for p in deepcopy(pairlist):
if p not in tickers:
pairlist.remove(p)
return pairlist
def create_pair_list(self, pairs: List[str], timeframe: str = None) -> ListPairsWithTimeframes:
"""
Create list of pair tuples with (pair, ticker_interval)
"""
return [(pair, timeframe or self._config['ticker_interval']) for pair in pairs]