moved interest to exchange class method

freqtrade/exchange/binance.py

@@ -2,6 +2,8 @@
 import json
 import logging
 from datetime import datetime
+from decimal import Decimal
+from math import ceil
 from pathlib import Path
 from typing import Dict, List, Optional, Tuple
 
@@ -358,3 +360,23 @@ class Binance(Exchange):
         else:
             raise OperationalException(
                 "Freqtrade only supports isolated futures for leverage trading")
+
+    @classmethod
+    def interest(
+        cls,
+        borrowed: Decimal,
+        rate: Decimal,
+        hours: Decimal
+    ) -> Decimal:
+        """
+        Equation to calculate interest on margin trades
+
+        :param borrowed: The amount of currency being borrowed
+        :param rate: The rate of interest (i.e daily interest rate)
+        :param hours: The time in hours that the currency has been borrowed for
+
+        Returns: The amount of interest owed (currency matches borrowed)
+        """
+        twenty_four = Decimal(24.0)
+
+        return borrowed * rate * ceil(hours)/twenty_four

freqtrade/exchange/exchange.py

@@ -8,6 +8,7 @@ import inspect
 import logging
 from copy import deepcopy
 from datetime import datetime, timedelta, timezone
+from decimal import Decimal
 from math import ceil
 from typing import Any, Dict, List, Literal, Optional, Tuple, Union
 
@@ -2160,6 +2161,28 @@ class Exchange:
             raise OperationalException(
                 "Freqtrade only supports isolated futures for leverage trading")
 
+    @classmethod
+    def interest(
+        cls,
+        borrowed: Decimal,
+        rate: Decimal,
+        hours: Decimal
+    ) -> Decimal:
+        """
+        Equation to calculate interest on margin trades
+
+        :param borrowed: The amount of currency being borrowed
+        :param rate: The rate of interest (i.e daily interest rate)
+        :param hours: The time in hours that the currency has been borrowed for
+
+        Raises:
+            OperationalException: Raised if freqtrade does
+            not support margin trading for this exchange
+
+        Returns: The amount of interest owed (currency matches borrowed)
+        """
+        raise OperationalException('interest not implemented for ' + cls.__name__)
+
 
 def is_exchange_known_ccxt(exchange_name: str, ccxt_module: CcxtModuleType = None) -> bool:
     return exchange_name in ccxt_exchanges(ccxt_module)

freqtrade/exchange/ftx.py

@@ -1,5 +1,7 @@
 """ FTX exchange subclass """
 import logging
+from decimal import Decimal
+from math import ceil
 from typing import Any, Dict, List, Tuple
 
 import ccxt
@@ -162,3 +164,25 @@ class Ftx(Exchange):
         if order['type'] == 'stop':
             return safe_value_fallback2(order, order, 'id_stop', 'id')
         return order['id']
+
+    @classmethod
+    def interest(
+        cls,
+        borrowed: Decimal,
+        rate: Decimal,
+        hours: Decimal
+    ) -> Decimal:
+        """
+        Equation to calculate interest on margin trades
+
+        :param borrowed: The amount of currency being borrowed
+        :param rate: The rate of interest (i.e daily interest rate)
+        :param hours: The time in hours that the currency has been borrowed for
+
+        Returns: The amount of interest owed (currency matches borrowed)
+        """
+        twenty_four = Decimal(24.0)
+
+        # As Explained under #Interest rates section in
+        # https://help.ftx.com/hc/en-us/articles/360053007671-Spot-Margin-Trading-Explainer
+        return borrowed * rate * ceil(hours)/twenty_four

freqtrade/exchange/kraken.py

@@ -1,6 +1,8 @@
 """ Kraken exchange subclass """
 import logging
 from datetime import datetime
+from decimal import Decimal
+from math import ceil
 from typing import Any, Dict, List, Optional, Tuple
 
 import ccxt
@@ -206,3 +208,26 @@ class Kraken(Exchange):
             fees = sum(df['open_fund'] * df['open_mark'] * amount * time_in_ratio)
 
         return fees if is_short else -fees
+
+    @classmethod
+    def interest(
+        cls,
+        borrowed: Decimal,
+        rate: Decimal,
+        hours: Decimal
+    ) -> Decimal:
+        """
+        Equation to calculate interest on margin trades
+
+        :param borrowed: The amount of currency being borrowed
+        :param rate: The rate of interest (i.e daily interest rate)
+        :param hours: The time in hours that the currency has been borrowed for
+
+        Returns: The amount of interest owed (currency matches borrowed)
+        """
+
+        one = Decimal(1.0)
+        four = Decimal(4.0)
+
+        # Rounded based on https://kraken-fees-calculator.github.io/
+        return borrowed * rate * (one+ceil(hours/four))

freqtrade/leverage/__init__.py

@@ -1,2 +0,0 @@
-# flake8: noqa: F401
-from freqtrade.leverage.interest import interest

freqtrade/leverage/interest.py

@@ -1,43 +0,0 @@
-from decimal import Decimal
-from math import ceil
-
-from freqtrade.exceptions import OperationalException
-
-
-one = Decimal(1.0)
-four = Decimal(4.0)
-twenty_four = Decimal(24.0)
-
-
-def interest(
-    exchange_name: str,
-    borrowed: Decimal,
-    rate: Decimal,
-    hours: Decimal
-) -> Decimal:
-    """
-    Equation to calculate interest on margin trades
-
-    :param exchange_name: The exchanged being trading on
-    :param borrowed: The amount of currency being borrowed
-    :param rate: The rate of interest (i.e daily interest rate)
-    :param hours: The time in hours that the currency has been borrowed for
-
-    Raises:
-        OperationalException: Raised if freqtrade does
-        not support margin trading for this exchange
-
-    Returns: The amount of interest owed (currency matches borrowed)
-    """
-    exchange_name = exchange_name.lower()
-    if exchange_name == "binance":
-        return borrowed * rate * ceil(hours)/twenty_four
-    elif exchange_name == "kraken":
-        # Rounded based on https://kraken-fees-calculator.github.io/
-        return borrowed * rate * (one+ceil(hours/four))
-    elif exchange_name == "ftx":
-        # As Explained under #Interest rates section in
-        # https://help.ftx.com/hc/en-us/articles/360053007671-Spot-Margin-Trading-Explainer
-        return borrowed * rate * ceil(hours)/twenty_four
-    else:
-        raise OperationalException(f"Leverage not available on {exchange_name} with freqtrade")