WIP: refactoring so that a context manager implementing read method i…

…s required

src/pyaro/timeseries/Reader.py

@@ -1,8 +1,9 @@
 import abc
+from contextlib import contextmanager
+
 from .Data import Data
 from .Station import Station
 from .Filter import Filter, filters
-# from contextlib import contextmanager
 
 
 class Reader(abc.ABC):
@@ -21,14 +22,17 @@ def __init__(self, filename_or_obj_or_url, filters=None, **kwargs):
         pass
 
     @abc.abstractmethod
-    def read(self,):
+    @contextmanager
+    def read(self):
         """define read method. All needed parameters should be put into self
         by the __init__ method
 
-        This function is usually called after the Engine's open function.'
+        This function is usually called after the Engine's open function.
+        Should implement context manager
         """
-        pass
+        yield self
 
+    @abc.abstractmethod
     def metadata(self) -> dict[str, str]:
         """Metadata set by the datasource.
 
@@ -75,18 +79,3 @@ def close(self) -> None:
         Implement as dummy (pass) if no cleanup needed.
         """
         pass
-
-    # def __enter__(self):
-    #     """Context managaer function
-    #
-    #     :return: context-object
-    #     """
-    #     return self
-    #
-    # def __exit__(self, type, value, traceback):
-    #     """Context manager function.
-    #
-    #     The default implementation calls the close function.
-    #     """
-    #     self.close()
-    #     return

src/pyaro/timeseries/Wrappers.py

@@ -46,6 +46,15 @@ def data(self, varname):
         data._set_variable(varname)
         return data
 
+    def metadata(self):
+        """Get the metadata from the reader
+        NOT changing the variable name to the newly given ones for the moment
+
+        :return: metadata from the original reader class
+        """
+        metadata = self._reader.metadata()
+        return metadata
+
     def stations(self):
         return self._reader.stations()
 
@@ -59,12 +68,15 @@ def variables(self):
     def close(self):
         self._reader.close()
 
+    @contextmanager
     def read(self,):
         """define read method. All needed parameters should be put into self
         by the __init__ method
 
         This function is usually called after the Engine's open function.'
         """
-        return self._reader.read()
+        with self._reader.read() as ts:
+            yield self
+        # return self._reader.read()