From 52e9528361b73bced2f34c77d7bbbebaa1b7fa23 Mon Sep 17 00:00:00 2001
From: Matthias <xmatthias@outlook.com>
Date: Tue, 11 Oct 2022 19:33:07 +0000
Subject: [PATCH] Improve ticker type

---
 freqtrade/exchange/binance.py             |  3 ++-
 freqtrade/exchange/types.py               | 15 +++++++++++++--
 freqtrade/plugins/pairlist/PriceFilter.py |  6 +++---
 3 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/freqtrade/exchange/binance.py b/freqtrade/exchange/binance.py
index a0d4b2d82..6d818bab9 100644
--- a/freqtrade/exchange/binance.py
+++ b/freqtrade/exchange/binance.py
@@ -11,6 +11,7 @@ from freqtrade.enums import CandleType, MarginMode, TradingMode
 from freqtrade.exceptions import DDosProtection, OperationalException, TemporaryError
 from freqtrade.exchange import Exchange
 from freqtrade.exchange.common import retrier
+from freqtrade.exchange.types import Tickers
 from freqtrade.misc import deep_merge_dicts, json_load
 
 
@@ -59,7 +60,7 @@ class Binance(Exchange):
                 )
             ))
 
-    def get_tickers(self, symbols: Optional[List[str]] = None, cached: bool = False) -> Dict:
+    def get_tickers(self, symbols: Optional[List[str]] = None, cached: bool = False) -> Tickers:
         tickers = super().get_tickers(symbols=symbols, cached=cached)
         if self.trading_mode == TradingMode.FUTURES:
             # Binance's future result has no bid/ask values.
diff --git a/freqtrade/exchange/types.py b/freqtrade/exchange/types.py
index 6504381dc..a60b454d4 100644
--- a/freqtrade/exchange/types.py
+++ b/freqtrade/exchange/types.py
@@ -1,5 +1,16 @@
-from typing import Any, Dict
+from typing import Dict, Optional, TypedDict
+
+
+class Ticker(TypedDict):
+    symbol: str
+    ask: Optional[float]
+    askVolume: Optional[float]
+    bid: Optional[float]
+    bidVolume: Optional[float]
+    last: Optional[float]
+    quoteVolume: Optional[float]
+    baseVolume: Optional[float]
+    # Several more - only listing required.
 
 
-Ticker = Dict[str, Any]
 Tickers = Dict[str, Ticker]
diff --git a/freqtrade/plugins/pairlist/PriceFilter.py b/freqtrade/plugins/pairlist/PriceFilter.py
index da41e9239..4d23de792 100644
--- a/freqtrade/plugins/pairlist/PriceFilter.py
+++ b/freqtrade/plugins/pairlist/PriceFilter.py
@@ -72,13 +72,13 @@ class PriceFilter(IPairList):
         :param ticker: ticker dict as returned from ccxt.fetch_ticker
         :return: True if the pair can stay, false if it should be removed
         """
-        if not ticker or ticker.get('last', None) is None or ticker.get('last') == 0:
+        if ticker and 'last' in ticker and ticker['last'] is not None and ticker.get('last') != 0:
+            price: float = ticker['last']
+        else:
             self.log_once(f"Removed {pair} from whitelist, because "
                           "ticker['last'] is empty (Usually no trade in the last 24h).",
                           logger.info)
             return False
-        else:
-            price: float = ticker['last']
 
         # Perform low_price_ratio check.
         if self._low_price_ratio != 0: