refactoring freqai backtesting

freqtrade/freqai/data_kitchen.py

@@ -1,6 +1,7 @@
 import copy
 import datetime
 import logging
+import os
 import shutil
 from pathlib import Path
 from typing import Any, Dict, List, Tuple
@@ -780,9 +781,10 @@ class FreqaiDataKitchen:
         weights = np.exp(-np.arange(num_weights) / (wfactor * num_weights))[::-1]
         return weights
 
-    def append_predictions(self, predictions: DataFrame, do_predict: npt.ArrayLike) -> None:
+    def get_predictions_to_append(self, predictions: DataFrame,
+                                  do_predict: npt.ArrayLike) -> DataFrame:
         """
-        Append backtest prediction from current backtest period to all previous periods
+        Get backtest prediction from current backtest period
         """
 
         append_df = DataFrame()
@@ -797,12 +799,19 @@ class FreqaiDataKitchen:
         if self.freqai_config["feature_parameters"].get("DI_threshold", 0) > 0:
             append_df["DI_values"] = self.DI_values
 
+        return append_df
+
+    def append_predictions(self, append_df: DataFrame) -> None:
+        """
+        Append backtest prediction from current backtest period to all previous periods
+        """
+
         if self.full_df.empty:
             self.full_df = append_df
         else:
             self.full_df = pd.concat([self.full_df, append_df], axis=0)
 
-        return
+        return append_df
 
     def fill_predictions(self, dataframe):
         """
@@ -1089,3 +1098,25 @@ class FreqaiDataKitchen:
         if self.unique_classes:
             for label in self.unique_classes:
                 self.unique_class_list += list(self.unique_classes[label])
+
+    def save_backtesting_prediction(
+        self, file_name: str, root_folder: str, append_df: DataFrame
+    ) -> None:
+
+        """
+        Save prediction dataframe from backtesting to h5 file format
+        :param file_name: h5 file name
+        :param root_folder: folder to save h5 file
+        """
+        os.makedirs(root_folder, exist_ok=True)
+        append_df.to_hdf(file_name, key='append_df', mode='w')
+
+    def get_backtesting_prediction(self, prediction_file_name: str) -> DataFrame:
+        """
+        Retrive from disk the prediction dataframe
+        :param prediction_file_name: prediction file full path
+        :return:
+        :Dataframe: Backtesting prediction from current backtesting period
+        """
+        append_df = pd.read_hdf(prediction_file_name)
+        return append_df

freqtrade/freqai/freqai_interface.py

@@ -224,13 +224,26 @@ class IFreqaiModel(ABC):
                 "trains"
             )
 
+            trained_timestamp_int = int(trained_timestamp.stopts)
             dk.data_path = Path(
                 dk.full_path
                 /
-                f"sub-train-{metadata['pair'].split('/')[0]}_{int(trained_timestamp.stopts)}"
+                f"sub-train-{metadata['pair'].split('/')[0]}_{trained_timestamp_int}"
                 )
+
+            if self.backtest_prediction_exists(
+                metadata["pair"], dk, trained_timestamp=trained_timestamp_int
+            ):
+                prediction_filename, _ = self.get_backtesting_prediction_file_name(
+                    metadata["pair"],
+                    dk,
+                    trained_timestamp=int(trained_timestamp.stopts))
+
+                append_df = dk.get_backtesting_prediction(prediction_filename)
+                dk.append_predictions(append_df)
+            else:
                 if not self.model_exists(
-                metadata["pair"], dk, trained_timestamp=int(trained_timestamp.stopts)
+                    metadata["pair"], dk, trained_timestamp=trained_timestamp_int
                 ):
                     dk.find_features(dataframe_train)
                     self.model = self.train(dataframe_train, metadata["pair"], dk)
@@ -244,8 +257,17 @@ class IFreqaiModel(ABC):
                 self.check_if_feature_list_matches_strategy(dataframe_train, dk)
 
                 pred_df, do_preds = self.predict(dataframe_backtest, dk)
+                append_df = dk.get_predictions_to_append(pred_df, do_preds)
+                dk.append_predictions(append_df)
 
-            dk.append_predictions(pred_df, do_preds)
+                prediction_file_name, root_prediction = self.get_backtesting_prediction_file_name(
+                    metadata["pair"],
+                    dk,
+                    trained_timestamp_int)
+
+                dk.save_backtesting_prediction(prediction_file_name,
+                                               root_prediction,
+                                               append_df)
 
         dk.fill_predictions(dataframe)
 
@@ -643,6 +665,56 @@ class IFreqaiModel(ABC):
                 self.train_time = 0
         return
 
+    def backtest_prediction_exists(
+        self,
+        pair: str,
+        dk: FreqaiDataKitchen,
+        trained_timestamp: int,
+        scanning: bool = False,
+    ) -> bool:
+        """
+        Given a pair and path, check if a backtesting prediction already exists
+        :param pair: pair e.g. BTC/USD
+        :param path: path to prediction
+        :return:
+        :boolean: whether the prediction file exists or not.
+        """
+        if not self.live:
+            prediction_file_name, _ = self.get_backtesting_prediction_file_name(
+                pair, dk, trained_timestamp
+            )
+            path_to_predictionfile = Path(prediction_file_name)
+
+            file_exists = path_to_predictionfile.is_file()
+            if file_exists and not scanning:
+                logger.info("Found backtesting prediction file at %s", prediction_file_name)
+            elif not scanning:
+                logger.info(
+                    "Could not find backtesting prediction file at %s", prediction_file_name
+                )
+            return file_exists
+        else:
+            return False
+
+    def get_backtesting_prediction_file_name(
+        self, pair: str, dk: FreqaiDataKitchen, trained_timestamp: int
+    ):
+        """
+        Given a pair, path and a trained timestamp,
+        returns the path and name of the predictions file
+        :param pair: pair e.g. BTC/USD
+        :param dk: FreqaiDataKitchen
+        :trained_timestamp: current backtesting timestamp period
+        :return:
+        :str: prediction file name
+        :str: prediction root path
+        """
+        coin, _ = pair.split("/")
+        prediction_base_filename = f"{coin.lower()}_{trained_timestamp}"
+        root_prediction = f'{dk.full_path}/backtesting_predictions'
+        prediction_file_name = f"{root_prediction}/{prediction_base_filename}_predictions.h5"
+        return prediction_file_name, root_prediction
+
     # Following methods which are overridden by user made prediction models.
     # See freqai/prediction_models/CatboostPredictionModel.py for an example.