freqtrade_origin/freqtrade/plugins/pairlist/pairlist_helpers.py
2021-01-23 20:40:27 +01:00

43 lines
1.8 KiB
Python

import re
from typing import List
def expand_pairlist(wildcardpl: List[str], available_pairs: List[str],
keep_invalid: bool = False) -> List[str]:
"""
Expand pairlist potentially containing wildcards based on available markets.
This will implicitly filter all pairs in the wildcard-list which are not in available_pairs.
:param wildcardpl: List of Pairlists, which may contain regex
:param available_pairs: List of all available pairs (`exchange.get_markets().keys()`)
:param keep_invalid: If sets to True, drops invalid pairs silently while expanding regexes
:return expanded pairlist, with Regexes from wildcardpl applied to match all available pairs.
:raises: ValueError if a wildcard is invalid (like '*/BTC' - which should be `.*/BTC`)
"""
result = []
if keep_invalid:
for pair_wc in wildcardpl:
try:
comp = re.compile(pair_wc)
result_partial = [
pair for pair in available_pairs if re.fullmatch(comp, pair)
]
# Add all matching pairs.
# If there are no matching pairs (Pair not on exchange) keep it.
result += result_partial or [pair_wc]
except re.error as err:
raise ValueError(f"Wildcard error in {pair_wc}, {err}")
for element in result:
if not re.fullmatch(r'^[A-Za-z0-9/-]+$', element):
result.remove(element)
else:
for pair_wc in wildcardpl:
try:
comp = re.compile(pair_wc)
result += [
pair for pair in available_pairs if re.fullmatch(comp, pair)
]
except re.error as err:
raise ValueError(f"Wildcard error in {pair_wc}, {err}")
return result