Added liquidation_price function

freqtrade/persistence/models.py

@@ -14,9 +14,10 @@ from sqlalchemy.pool import StaticPool
 from sqlalchemy.sql.schema import UniqueConstraint
 
 from freqtrade.constants import DATETIME_PRINT_FORMAT, NON_OPEN_EXCHANGE_STATES
-from freqtrade.enums import SellType, TradingMode
+from freqtrade.enums import Collateral, SellType, TradingMode
 from freqtrade.exceptions import DependencyException, OperationalException
 from freqtrade.leverage import interest
+from freqtrade.leverage import liquidation_price
 from freqtrade.misc import safe_value_fallback
 from freqtrade.persistence.migrations import check_migrate
 
@@ -333,7 +334,7 @@ class LocalTrade():
         for key in kwargs:
             setattr(self, key, kwargs[key])
         if self.isolated_liq:
-            self.set_isolated_liq(self.isolated_liq)
+            self.set_isolated_liq(isolated_liq=self.isolated_liq)
         self.recalc_open_trade_value()
         if self.trading_mode == TradingMode.MARGIN and self.interest_rate is None:
             raise OperationalException(
@@ -362,11 +363,25 @@ class LocalTrade():
             self.stop_loss_pct = -1 * abs(percent)
         self.stoploss_last_update = datetime.utcnow()
 
-    def set_isolated_liq(self, isolated_liq: float):
+    def set_isolated_liq(self, isolated_liq: Optional[float]):
         """
         Method you should use to set self.liquidation price.
         Assures stop_loss is not passed the liquidation price
         """
+        if not isolated_liq:
+            isolated_liq = liquidation_price(
+                exchange_name=self.exchange,
+                open_rate=self.open_rate,
+                is_short=self.is_short,
+                leverage=self.leverage,
+                trading_mode=self.trading_mode,
+                collateral=Collateral.ISOLATED
+            )
+        if isolated_liq is None:
+            raise OperationalException(
+                "leverage/isolated_liq returned None. This exception should never happen"
+            )
+
         if self.stop_loss is not None:
             if self.is_short:
                 self.stop_loss = min(self.stop_loss, isolated_liq)