Add fetch_order_emulated to support exchanges without proper fetch_order method

freqtrade/exchange/exchange.py

@@ -1260,11 +1260,43 @@ class Exchange:
         except ccxt.BaseError as e:
             raise OperationalException(e) from e
 
+    def fetch_order_emulated(self, order_id: str, pair: str, params: Dict) -> Dict:
+        """
+        Emulated fetch_order if the exchange doesn't support fetch_order, but requires separate
+        calls for open and closed orders.
+        """
+        try:
+            order = self._api.fetch_open_order(order_id, pair, params=params)
+            self._log_exchange_response('fetch_open_order', order)
+            order = self._order_contracts_to_amount(order)
+            return order
+        except ccxt.OrderNotFound:
+            try:
+                order = self._api.fetch_closed_order(order_id, pair, params=params)
+                self._log_exchange_response('fetch_closed_order', order)
+                order = self._order_contracts_to_amount(order)
+                return order
+            except ccxt.OrderNotFound as e:
+                raise RetryableOrderError(
+                    f'Order not found (pair: {pair} id: {order_id}). Message: {e}') from e
+        except ccxt.InvalidOrder as e:
+            raise InvalidOrderException(
+                f'Tried to get an invalid order (pair: {pair} id: {order_id}). Message: {e}') from e
+        except ccxt.DDoSProtection as e:
+            raise DDosProtection(e) from e
+        except (ccxt.NetworkError, ccxt.ExchangeError) as e:
+            raise TemporaryError(
+                f'Could not get order due to {e.__class__.__name__}. Message: {e}') from e
+        except ccxt.BaseError as e:
+            raise OperationalException(e) from e
+
     @retrier(retries=API_FETCH_ORDER_RETRY_COUNT)
     def fetch_order(self, order_id: str, pair: str, params: Dict = {}) -> Dict:
         if self._config['dry_run']:
             return self.fetch_dry_run_order(order_id)
         try:
+            if not self.exchange_has('fetchOrder'):
+                return self.fetch_order_emulated(order_id, pair, params)
             order = self._api.fetch_order(order_id, pair, params=params)
             self._log_exchange_response('fetch_order', order)
             order = self._order_contracts_to_amount(order)