Fix unreliable backtest-result when using webserver mode

freqtrade/data/dataprovider.py

@@ -149,6 +149,8 @@ class DataProvider:
         Clear pair dataframe cache.
         """
         self.__cached_pairs = {}
+        self.__cached_pairs_backtesting = {}
+        self.__slice_index = 0
 
     # Exchange functions
 

freqtrade/optimize/backtesting.py

@@ -85,18 +85,7 @@ class Backtesting:
                                        "configuration or as cli argument `--timeframe 5m`")
         self.timeframe = str(self.config.get('timeframe'))
         self.timeframe_min = timeframe_to_minutes(self.timeframe)
-        # Load detail timeframe if specified
+        self.init_backtest_detail()
-        self.timeframe_detail = str(self.config.get('timeframe_detail', ''))
-        if self.timeframe_detail:
-            self.timeframe_detail_min = timeframe_to_minutes(self.timeframe_detail)
-            if self.timeframe_min <= self.timeframe_detail_min:
-                raise OperationalException(
-                    "Detail timeframe must be smaller than strategy timeframe.")
-
-        else:
-            self.timeframe_detail_min = 0
-        self.detail_data: Dict[str, DataFrame] = {}
-
         self.pairlists = PairListManager(self.exchange, self.config)
         if 'VolumePairList' in self.pairlists.name_list:
             raise OperationalException("VolumePairList not allowed for backtesting.")
@@ -119,14 +108,6 @@ class Backtesting:
         else:
             self.fee = self.exchange.get_fee(symbol=self.pairlists.whitelist[0])
 
-        Trade.use_db = False
-        Trade.reset_trades()
-        PairLocks.timeframe = self.config['timeframe']
-        PairLocks.use_db = False
-        PairLocks.reset_locks()
-
-        self.wallets = Wallets(self.config, self.exchange, log=False)
-
         self.timerange = TimeRange.parse_timerange(
             None if self.config.get('timerange') is None else str(self.config.get('timerange')))
 
@@ -135,9 +116,7 @@ class Backtesting:
         # Add maximum startup candle count to configuration for informative pairs support
         self.config['startup_candle_count'] = self.required_startup
         self.exchange.validate_required_startup_candles(self.required_startup, self.timeframe)
-
+        self.init_backtest()
-        self.progress = BTProgress()
-        self.abort = False
 
     def __del__(self):
         self.cleanup()
@@ -147,6 +126,28 @@ class Backtesting:
         PairLocks.use_db = True
         Trade.use_db = True
 
+    def init_backtest_detail(self):
+        # Load detail timeframe if specified
+        self.timeframe_detail = str(self.config.get('timeframe_detail', ''))
+        if self.timeframe_detail:
+            self.timeframe_detail_min = timeframe_to_minutes(self.timeframe_detail)
+            if self.timeframe_min <= self.timeframe_detail_min:
+                raise OperationalException(
+                    "Detail timeframe must be smaller than strategy timeframe.")
+
+        else:
+            self.timeframe_detail_min = 0
+        self.detail_data: Dict[str, DataFrame] = {}
+
+    def init_backtest(self):
+
+        self.prepare_backtest(False)
+
+        self.wallets = Wallets(self.config, self.exchange, log=False)
+
+        self.progress = BTProgress()
+        self.abort = False
+
     def _set_strategy(self, strategy: IStrategy):
         """
         Load strategy into backtesting
@@ -226,6 +227,7 @@ class Backtesting:
         Trade.reset_trades()
         self.rejected_trades = 0
         self.dataprovider.clear_cache()
+        if enable_protections:
             self._load_protections(self.strategy)
 
     def check_abort(self):

freqtrade/rpc/api_server/api_backtest.py

@@ -47,33 +47,34 @@ async def api_start_backtest(bt_settings: BacktestRequest, background_tasks: Bac
                 not ApiServer._bt
                 or lastconfig.get('timeframe') != strat.timeframe
                 or lastconfig.get('timeframe_detail') != btconfig.get('timeframe_detail')
-                or lastconfig.get('dry_run_wallet') != btconfig.get('dry_run_wallet', 0)
                 or lastconfig.get('timerange') != btconfig['timerange']
             ):
                 from freqtrade.optimize.backtesting import Backtesting
                 ApiServer._bt = Backtesting(btconfig)
                 if ApiServer._bt.timeframe_detail:
                     ApiServer._bt.load_bt_data_detail()
-
+            else:
+                ApiServer._bt.config = btconfig
+                ApiServer._bt.init_backtest()
             # Only reload data if timeframe changed.
             if (
                 not ApiServer._bt_data
                 or not ApiServer._bt_timerange
-                or lastconfig.get('stake_amount') != btconfig.get('stake_amount')
-                or lastconfig.get('enable_protections') != btconfig.get('enable_protections')
-                or lastconfig.get('protections') != btconfig.get('protections', [])
                 or lastconfig.get('timeframe') != strat.timeframe
             ):
+                ApiServer._bt_data, ApiServer._bt_timerange = ApiServer._bt.load_bt_data()
+
                 lastconfig['timerange'] = btconfig['timerange']
+                lastconfig['timeframe'] = strat.timeframe
+
             lastconfig['protections'] = btconfig.get('protections', [])
             lastconfig['enable_protections'] = btconfig.get('enable_protections')
             lastconfig['dry_run_wallet'] = btconfig.get('dry_run_wallet')
-                lastconfig['timeframe'] = strat.timeframe
-                ApiServer._bt_data, ApiServer._bt_timerange = ApiServer._bt.load_bt_data()
 
             ApiServer._bt.abort = False
             min_date, max_date = ApiServer._bt.backtest_one_strategy(
                 strat, ApiServer._bt_data, ApiServer._bt_timerange)
+
             ApiServer._bt.results = generate_backtest_stats(
                 ApiServer._bt_data, ApiServer._bt.all_results,
                 min_date=min_date, max_date=max_date)