Supporting shared processor (#596)

* Supporting shared processor

* fix readonly reverse bug

* remove pytests dependency

* with fit bug

* fix parameter error

qlib/data/dataset/handler.py

@@ -295,11 +295,14 @@ class DataHandlerLP(DataHandler):
 
     # process type
     PTYPE_I = "independent"
-    # - self._infer will be processed by infer_processors
+    # - self._infer will be processed by shared_processors + infer_processors
-    # - self._learn will be processed by learn_processors
+    # - self._learn will be processed by shared_processors + learn_processors
+
+    # NOTE:
     PTYPE_A = "append"
-    # - self._infer will be processed by infer_processors
+
-    # - self._learn will be processed by infer_processors + learn_processors
+    # - self._infer will be processed by shared_processors + infer_processors
+    # - self._learn will be processed by shared_processors + infer_processors + learn_processors
     #   - (e.g. self._infer processed by learn_processors )
 
     def __init__(
@@ -308,8 +311,9 @@ class DataHandlerLP(DataHandler):
         start_time=None,
         end_time=None,
         data_loader: Union[dict, str, DataLoader] = None,
-        infer_processors=[],
+        infer_processors: List = [],
-        learn_processors=[],
+        learn_processors: List = [],
+        shared_processors: List = [],
         process_type=PTYPE_A,
         drop_raw=False,
         **kwargs,
@@ -360,7 +364,8 @@ class DataHandlerLP(DataHandler):
         # Setup preprocessor
         self.infer_processors = []  # for lint
         self.learn_processors = []  # for lint
-        for pname in "infer_processors", "learn_processors":
+        self.shared_processors = []  # for lint
+        for pname in "infer_processors", "learn_processors", "shared_processors":
             for proc in locals()[pname]:
                 getattr(self, pname).append(
                     init_instance_by_config(
@@ -375,9 +380,12 @@ class DataHandlerLP(DataHandler):
         super().__init__(instruments, start_time, end_time, data_loader, **kwargs)
 
     def get_all_processors(self):
-        return self.infer_processors + self.learn_processors
+        return self.shared_processors + self.infer_processors + self.learn_processors
 
     def fit(self):
+        """
+        fit data without processing the data
+        """
         for proc in self.get_all_processors():
             with TimeInspector.logt(f"{proc.__class__.__name__}"):
                 proc.fit(self._data)
@@ -390,30 +398,68 @@ class DataHandlerLP(DataHandler):
         """
         self.process_data(with_fit=True)
 
+    @staticmethod
+    def _run_proc_l(
+        df: pd.DataFrame, proc_l: List[processor_module.Processor], with_fit: bool, check_for_infer: bool
+    ) -> pd.DataFrame:
+        for proc in proc_l:
+            if check_for_infer and not proc.is_for_infer():
+                raise TypeError("Only processors usable for inference can be used in `infer_processors` ")
+            with TimeInspector.logt(f"{proc.__class__.__name__}"):
+                if with_fit:
+                    proc.fit(df)
+                df = proc(df)
+        return df
+
+    @staticmethod
+    def _is_proc_readonly(proc_l: List[processor_module.Processor]):
+        """
+        NOTE: it will return True if `len(proc_l) == 0`
+        """
+        for p in proc_l:
+            if not p.readonly():
+                return False
+        return True
+
     def process_data(self, with_fit: bool = False):
         """
         process_data data. Fun `processor.fit` if necessary
 
+        Notation: (data)  [processor]
+
+        # data processing flow of self.process_type == DataHandlerLP.PTYPE_I
+        (self._data)-[shared_processors]-(_shared_df)-[learn_processors]-(_learn_df)
+                                               \
+                                                -[infer_processors]-(_infer_df)
+
+        # data processing flow of self.process_type == DataHandlerLP.PTYPE_A
+        (self._data)-[shared_processors]-(_shared_df)-[infer_processors]-(_infer_df)-[learn_processors]-(_learn_df)
+
         Parameters
         ----------
         with_fit : bool
             The input of the `fit` will be the output of the previous processor
         """
-        # data for inference
+        # shared data processors
-        _infer_df = self._data
+        # 1) assign
-        if len(self.infer_processors) > 0 and not self.drop_raw:  # avoid modifying the original  data
+        _shared_df = self._data
-            _infer_df = _infer_df.copy()
+        if not self._is_proc_readonly(self.shared_processors):  # avoid modifying the original data
+            _shared_df = _shared_df.copy()
+        # 2) process
+        _shared_df = self._run_proc_l(_shared_df, self.shared_processors, with_fit=with_fit, check_for_infer=True)
+
+        # data for inference
+        # 1) assign
+        _infer_df = _shared_df
+        if not self._is_proc_readonly(self.infer_processors):  # avoid modifying the original data
+            _infer_df = _infer_df.copy()
+        # 2) process
+        _infer_df = self._run_proc_l(_infer_df, self.infer_processors, with_fit=with_fit, check_for_infer=True)
 
-        for proc in self.infer_processors:
-            if not proc.is_for_infer():
-                raise TypeError("Only processors usable for inference can be used in `infer_processors` ")
-            with TimeInspector.logt(f"{proc.__class__.__name__}"):
-                if with_fit:
-                    proc.fit(_infer_df)
-                _infer_df = proc(_infer_df)
         self._infer = _infer_df
 
         # data for learning
+        # 1) assign
         if self.process_type == DataHandlerLP.PTYPE_I:
             _learn_df = self._data
         elif self.process_type == DataHandlerLP.PTYPE_A:
@@ -421,14 +467,11 @@ class DataHandlerLP(DataHandler):
             _learn_df = _infer_df
         else:
             raise NotImplementedError(f"This type of input is not supported")
-
+        if not self._is_proc_readonly(self.learn_processors):  # avoid modifying the original  data
-        if len(self.learn_processors) > 0:  # avoid modifying the original  data
             _learn_df = _learn_df.copy()
-        for proc in self.learn_processors:
+        # 2) process
-            with TimeInspector.logt(f"{proc.__class__.__name__}"):
+        _learn_df = self._run_proc_l(_learn_df, self.learn_processors, with_fit=with_fit, check_for_infer=False)
-                if with_fit:
+
-                    proc.fit(_learn_df)
-                _learn_df = proc(_learn_df)
         self._learn = _learn_df
 
         if self.drop_raw:

qlib/data/dataset/processor.py

@@ -73,6 +73,14 @@ class Processor(Serializable):
         """
         return True
 
+    def readonly(self) -> bool:
+        """
+        Does the processor treat the input data readonly (i.e. does not write the input data) when processsing
+
+        Knowning the readonly information is helpful to the Handler to avoid uncessary copy
+        """
+        return False
+
     def config(self, **kwargs):
         attr_list = {"fit_start_time", "fit_end_time"}
         for k, v in kwargs.items():
@@ -92,6 +100,9 @@ class DropnaProcessor(Processor):
     def __call__(self, df):
         return df.dropna(subset=get_group_columns(df, self.fields_group))
 
+    def readonly(self):
+        return True
+
 
 class DropnaLabel(DropnaProcessor):
     def __init__(self, fields_group="label"):
@@ -113,6 +124,9 @@ class DropCol(Processor):
             mask = df.columns.isin(self.col_list)
         return df.loc[:, ~mask]
 
+    def readonly(self):
+        return True
+
 
 class FilterCol(Processor):
     def __init__(self, fields_group="feature", col_list=[]):
@@ -128,6 +142,9 @@ class FilterCol(Processor):
         mask = df.columns.get_level_values(-1).isin(self.col_list)
         return df.loc[:, mask]
 
+    def readonly(self):
+        return True
+
 
 class TanhProcess(Processor):
     """Use tanh to process noise data"""

tests/storage_tests/test_storage.py

@@ -5,7 +5,6 @@
 from pathlib import Path
 from collections.abc import Iterable
 
-import pytest
 import numpy as np
 from qlib.tests import TestAutoData
 
@@ -33,13 +32,13 @@ class TestStorage(TestAutoData):
         print(f"calendar[-1]: {calendar[-1]}")
 
         calendar = CalendarStorage(freq="1min", future=False, provider_uri="not_found")
-        with pytest.raises(ValueError):
+        with self.assertRaises(ValueError):
             print(calendar.data)
 
-        with pytest.raises(ValueError):
+        with self.assertRaises(ValueError):
             print(calendar[:])
 
-        with pytest.raises(ValueError):
+        with self.assertRaises(ValueError):
             print(calendar[0])
 
     def test_instrument_storage(self):
@@ -90,10 +89,10 @@ class TestStorage(TestAutoData):
         print(f"instrument['SH600000']: {instrument['SH600000']}")
 
         instrument = InstrumentStorage(market="csi300", provider_uri="not_found")
-        with pytest.raises(ValueError):
+        with self.assertRaises(ValueError):
             print(instrument.data)
 
-        with pytest.raises(ValueError):
+        with self.assertRaises(ValueError):
             print(instrument["sSH600000"])
 
     def test_feature_storage(self):
@@ -152,7 +151,7 @@ class TestStorage(TestAutoData):
 
         feature = FeatureStorage(instrument="SH600004", field="close", freq="day", provider_uri=self.provider_uri)
 
-        with pytest.raises(IndexError):
+        with self.assertRaises(IndexError):
             print(feature[0])
         assert isinstance(
             feature[815][1], (float, np.float32)