gateio, ftx and binance all use same funding fee formula

freqtrade/exchange/binance.py

@@ -1,9 +1,8 @@
 """ Binance exchange subclass """
 import json
 import logging
-from datetime import datetime
 from pathlib import Path
-from typing import Any, Dict, List, Optional, Tuple
+from typing import Dict, List, Optional, Tuple
 
 import arrow
 import ccxt
@@ -30,13 +29,7 @@ class Binance(Exchange):
         "l2_limit_range": [5, 10, 20, 50, 100, 500, 1000],
     }
     funding_fee_times: List[int] = [0, 8, 16]  # hours of the day
-    _funding_interest_rates: Dict = {}  # TODO-lev: delete
-
-    def __init__(self, config: Dict[str, Any], validate: bool = True) -> None:
-        super().__init__(config, validate)
-        # TODO-lev: Uncomment once lev-exchange merged in
-        # if self.trading_mode == TradingMode.FUTURES:
-        # self._funding_interest_rates = self._get_funding_interest_rates()
+    # but the schedule won't check within this timeframe
 
     _supported_trading_mode_collateral_pairs: List[Tuple[TradingMode, Collateral]] = [
         # TradingMode.SPOT always supported and not required in this list
@@ -218,38 +211,6 @@ class Binance(Exchange):
         except ccxt.BaseError as e:
             raise OperationalException(e) from e
 
-    def _get_mark_price(self, pair: str, date: datetime) -> float:
-        raise OperationalException(f'_get_mark_price has not been implemented on {self.name}')
-
-    def _get_funding_rate(self, pair: str, premium_index: float) -> Optional[float]:
-        """
-            Get's the funding_rate for a pair at a specific date and time in the past
-        """
-        raise OperationalException(f'_get_mark_price has not been implemented on {self.name}')
-
-    def _get_funding_fee(
-        self,
-        pair: str,
-        contract_size: float,
-        mark_price: float,
-        funding_rate: Optional[float],
-    ) -> float:
-        """
-            Calculates a single funding fee
-            :param contract_size: The amount/quanity
-            :param mark_price: The price of the asset that the contract is based off of
-            :param funding_rate: the interest rate and the premium
-                - interest rate: 0.03% daily, BNBUSDT, LINKUSDT, and LTCUSDT are 0%
-                - premium: varies by price difference between the perpetual contract and mark price
-        """
-        if mark_price is None:
-            raise OperationalException("Mark price cannot be None for Binance._get_funding_fee")
-        nominal_value = mark_price * contract_size
-        if funding_rate is None:
-            raise OperationalException(
-                "Funding rate should never be none on Binance._get_funding_fee")
-        return nominal_value * funding_rate
-
     async def _async_get_historic_ohlcv(self, pair: str, timeframe: str,
                                         since_ms: int, is_new_pair: bool
                                         ) -> List:

freqtrade/exchange/exchange.py

@@ -1649,17 +1649,19 @@ class Exchange:
         self,
         pair: str,
         contract_size: float,
+        funding_rate: float,
         mark_price: float,
-        funding_rate: Optional[float]
     ) -> float:
         """
             Calculates a single funding fee
             :param contract_size: The amount/quanity
             :param mark_price: The price of the asset that the contract is based off of
             :param funding_rate: the interest rate and the premium
+                - interest rate:
                 - premium: varies by price difference between the perpetual contract and mark price
         """
-        raise OperationalException(f"Funding fee has not been implemented for {self.name}")
+        nominal_value = mark_price * contract_size
+        return nominal_value * funding_rate
 
     @retrier
     def _set_leverage(

freqtrade/exchange/ftx.py

@@ -1,6 +1,5 @@
 """ FTX exchange subclass """
 import logging
-from datetime import datetime
 from typing import Any, Dict, List, Optional, Tuple
 
 import ccxt
@@ -184,25 +183,3 @@ class Ftx(Exchange):
             :nominal_value: Here for super method, not used on FTX
         """
         return 20.0
-
-    def _get_funding_rate(self, pair: str, when: datetime) -> Optional[float]:
-        """FTX doesn't use this"""
-        return None
-
-    def _get_funding_fee(
-        self,
-        pair: str,
-        contract_size: float,
-        mark_price: float,
-        premium_index: Optional[float],
-        # index_price: float,
-        # interest_rate: float)
-    ) -> float:
-        """
-            Calculates a single funding fee
-            Always paid in USD on FTX  # TODO: How do we account for this
-            : param contract_size: The amount/quanity
-            : param mark_price: The price of the asset that the contract is based off of
-            : param funding_rate: Must be None on ftx
-        """
-        return (contract_size * mark_price) / 24