From 4bfab5e222a774416e43f9db58e5d8742f4f99ef Mon Sep 17 00:00:00 2001
From: hroff-1902 <hroff_raeyd9tzpttf@mail.ru>
Date: Mon, 18 May 2020 02:36:40 +0300
Subject: [PATCH] Add ShuffleFilter

---
 freqtrade/constants.py              |  2 +-
 freqtrade/pairlist/ShuffleFilter.py | 50 +++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+), 1 deletion(-)
 create mode 100644 freqtrade/pairlist/ShuffleFilter.py

diff --git a/freqtrade/constants.py b/freqtrade/constants.py
index e56586bbc..5d3b13eee 100644
--- a/freqtrade/constants.py
+++ b/freqtrade/constants.py
@@ -19,7 +19,7 @@ ORDERBOOK_SIDES = ['ask', 'bid']
 ORDERTYPE_POSSIBILITIES = ['limit', 'market']
 ORDERTIF_POSSIBILITIES = ['gtc', 'fok', 'ioc']
 AVAILABLE_PAIRLISTS = ['StaticPairList', 'VolumePairList',
-                       'PrecisionFilter', 'PriceFilter', 'SpreadFilter']
+                       'PrecisionFilter', 'PriceFilter', 'ShuffleFilter', 'SpreadFilter']
 AVAILABLE_DATAHANDLERS = ['json', 'jsongz']
 DRY_RUN_WALLET = 1000
 MATH_CLOSE_PREC = 1e-14  # Precision used for float comparisons
diff --git a/freqtrade/pairlist/ShuffleFilter.py b/freqtrade/pairlist/ShuffleFilter.py
new file mode 100644
index 000000000..a10a1af8b
--- /dev/null
+++ b/freqtrade/pairlist/ShuffleFilter.py
@@ -0,0 +1,50 @@
+"""
+Shuffle pair list filter
+"""
+import logging
+import random
+from typing import Dict, List
+
+from freqtrade.pairlist.IPairList import IPairList
+
+
+logger = logging.getLogger(__name__)
+
+
+class ShuffleFilter(IPairList):
+
+    def __init__(self, exchange, pairlistmanager, config, pairlistconfig: dict,
+                 pairlist_pos: int) -> None:
+        super().__init__(exchange, pairlistmanager, config, pairlistconfig, pairlist_pos)
+
+        self._seed = pairlistconfig.get('seed')
+        self._random = random.Random(self._seed)
+
+    @property
+    def needstickers(self) -> bool:
+        """
+        Boolean property defining if tickers are necessary.
+        If no Pairlist requries tickers, an empty List is passed
+        as tickers argument to filter_pairlist
+        """
+        return False
+
+    def short_desc(self) -> str:
+        """
+        Short whitelist method description - used for startup-messages
+        """
+        return (f"{self.name} - Shuffling pairs" +
+                (f", seed = {self._seed}." if self._seed is not None else "."))
+
+    def filter_pairlist(self, pairlist: List[str], tickers: Dict) -> List[str]:
+        """
+        Filters and sorts pairlist and returns the whitelist again.
+        Called on each bot iteration - please use internal caching if necessary
+        :param pairlist: pairlist to filter or sort
+        :param tickers: Tickers (from exchange.get_tickers()). May be cached.
+        :return: new whitelist
+        """
+        # Shuffle is done inplace
+        self._random.shuffle(pairlist)
+
+        return pairlist