Add LogOnAccess(property) and make AdvancedProperty(property), 2.1.0 (#28)

`LogOnAccess` - Property with logging on successful get/set/delete or failure.
Inherit `property` instead of full implementation
Cleanup last `object` subclassing

Author: penguinolog

README.rst

@@ -25,6 +25,8 @@ This package includes helpers for special cases:
 
 * `AdvancedProperty` - property with possibility to set class wide getter.
 
+* `LogOnAccess` - property with logging on successful get/set/delete or failure.
+
 SeparateClassMethod
 -------------------
 
@@ -124,6 +126,46 @@ Usage examples:
 
   class-wide getter receives class as argument. IDE's don't know about custom descriptors and substitutes `self` by default.
 
+LogOnAccess
+-----------
+
+This special case of property is useful in cases, where a lot of properties should be logged by similar way without writing a lot of code.
+
+Basic API is conform with `property`, but in addition it is possible to customize logger, log levels and log conditions.
+
+Usage example:
+
+  .. code-block:: python
+
+    class Target(object):
+
+      def init(self, val='ok')
+          self.val = val
+
+      def __repr__(self):
+          return "{cls}(val={self.val})".format(cls=self.__class__.__name__, self=self)
+
+      @advanced_descriptors.LogOnAccess
+      def ok(self):
+          return self.val
+
+      @ok.setter
+      def ok(self, val):
+          self.val = val
+
+      @ok.deleter
+      def ok(self):
+          self.val = ""
+
+      ok.logger = 'test_logger'
+      ok.log_level = logging.INFO
+      ok.exc_level = logging.ERROR
+      ok.log_object_repr = True  # As by default
+      ok.log_success = True  # As by default
+      ok.log_failure = True  # As by default
+      ok.log_traceback = True  # As by default
+      ok.override_name = None  # As by default: use original name
+
 Testing
 =======
 The main test mechanism for the package `advanced-descriptors` is using `tox`.

advanced_descriptors/__init__.py

@@ -15,10 +15,11 @@
 
 from .separate_class_method import SeparateClassMethod
 from .advanced_property import AdvancedProperty
+from .log_on_access import LogOnAccess
 
-__all__ = ("SeparateClassMethod", "AdvancedProperty")
+__all__ = ("SeparateClassMethod", "AdvancedProperty", "LogOnAccess")
 
-__version__ = "2.0.0"
+__version__ = "2.1.0"
 __author__ = "Alexey Stepanov"
 __author_email__ = "penguinolog@gmail.com"
 __maintainers__ = {

advanced_descriptors/advanced_property.py

@@ -20,22 +20,21 @@
 __all__ = ("AdvancedProperty",)
 
 
-class AdvancedProperty:
+class AdvancedProperty(property):
     """Property with class-wide getter.
 
     This property allows implementation of read-only getter for classes
     in additional to normal set of getter/setter/deleter on instance.
     Implements almost full @property interface,
     except __doc__ due to class-wide nature.
 
-    .. note:
+    .. versionadded:: 2.1.0 Inherit property
 
-        If class-wide setter/deleter required:
-        use normal property in metaclass.
+    .. note:: If class-wide setter/deleter required: use normal property in metaclass.
 
     Usage examples:
 
-    >>> class LikeNormalProperty(object):
+    >>> class LikeNormalProperty:
     ...     def __init__(self):
     ...         self.val = 42
     ...     @AdvancedProperty
@@ -67,7 +66,7 @@ class AdvancedProperty:
     ...
     AttributeError
 
-    >>> class ExtendedProperty(object):
+    >>> class ExtendedProperty:
     ...     def __init__(self):
     ...         self.val = 21
     ...     @AdvancedProperty
@@ -100,7 +99,7 @@ class AdvancedProperty:
     >>> ExtendedProperty.prop
     'self.val'
 
-    >>> class ClassProperty(object):
+    >>> class ClassProperty:
     ...     def _getter(cls):
     ...         return cls
     ...     prop = AdvancedProperty(fcget=_getter)  # special case
@@ -113,8 +112,6 @@ class AdvancedProperty:
     True
     """
 
-    __slots__ = ("__fget", "__fset", "__fdel", "__fcget")
-
     def __init__(
         self,
         fget: typing.Optional[typing.Callable[[typing.Any], typing.Any]] = None,
@@ -135,13 +132,11 @@ def __init__(
 
         .. note:: doc argument is not supported due to class wide getter usage.
         """
-        self.__fget = fget
-        self.__fset = fset
-        self.__fdel = fdel
+        super(AdvancedProperty, self).__init__(fget=fget, fset=fset, fdel=fdel)
 
         self.__fcget = fcget
 
-    def __get__(self, instance: typing.Optional[typing.Any], owner: typing.Any) -> typing.Any:
+    def __get__(self, instance: typing.Any, owner: typing.Any = None) -> typing.Any:
         """Get descriptor.
 
         :param instance: Owner class instance. Filled only if instance created, else None.
@@ -151,61 +146,11 @@ def __get__(self, instance: typing.Optional[typing.Any], owner: typing.Any) -> t
         :rtype: typing.Any
         :raises AttributeError: Getter is not available
         """
-        if instance is None or self.__fget is None:
+        if owner is not None and (instance is None or self.fget is None):
             if self.__fcget is None:
                 raise AttributeError()
             return self.__fcget(owner)
-        return self.__fget(instance)
-
-    def __set__(self, instance: typing.Any, value: typing.Any) -> None:
-        """Set descriptor.
-
-        :param instance: Owner class instance. Filled only if instance created, else None.
-        :type instance: typing.Optional
-        :param value: Value for setter
-        :raises AttributeError: Setter is not available
-        """
-        if self.__fset is None:
-            raise AttributeError()
-        self.__fset(instance, value)
-
-    def __delete__(self, instance: typing.Any) -> None:
-        """Delete descriptor.
-
-        :param instance: Owner class instance. Filled only if instance created, else None.
-        :type instance: typing.Optional
-        :raises AttributeError: Deleter is not available
-        """
-        if self.__fdel is None:
-            raise AttributeError()
-        self.__fdel(instance)
-
-    @property
-    def fget(self) -> typing.Optional[typing.Callable[[typing.Any], typing.Any]]:
-        """Getter instance.
-
-        :return: Normal getter instance
-        :rtype: typing.Optional[typing.Callable[[typing.Any, ], typing.Any]]
-        """
-        return self.__fget
-
-    @property
-    def fset(self) -> typing.Optional[typing.Callable[[typing.Any, typing.Any], None]]:
-        """Setter instance.
-
-        :return: Setter instance
-        :rtype: typing.Optional[typing.Callable[[typing.Any, typing.Any], None]]
-        """
-        return self.__fset
-
-    @property
-    def fdel(self) -> typing.Optional[typing.Callable[[typing.Any], None]]:
-        """Deleter instance.
-
-        :return: Deletter instance
-        :rtype: typing.Optional[typing.Callable[[typing.Any, ], None]]
-        """
-        return self.__fdel
+        return super(AdvancedProperty, self).__get__(instance, owner)
 
     @property
     def fcget(self) -> typing.Optional[typing.Callable[[typing.Any], typing.Any]]:
@@ -216,39 +161,6 @@ def fcget(self) -> typing.Optional[typing.Callable[[typing.Any], typing.Any]]:
         """
         return self.__fcget
 
-    def getter(self, fget: typing.Optional[typing.Callable[[typing.Any], typing.Any]]) -> "AdvancedProperty":
-        """Descriptor to change the getter on a property.
-
-        :param fget: new normal getter.
-        :type fget: typing.Optional[typing.Callable[[typing.Any, ], typing.Any]]
-        :return: AdvancedProperty
-        :rtype: AdvancedProperty
-        """
-        self.__fget = fget
-        return self
-
-    def setter(self, fset: typing.Optional[typing.Callable[[typing.Any, typing.Any], None]]) -> "AdvancedProperty":
-        """Descriptor to change the setter on a property.
-
-        :param fset: new setter.
-        :type fset: typing.Optional[typing.Callable[[typing.Any, typing.Any], None]]
-        :return: AdvancedProperty
-        :rtype: AdvancedProperty
-        """
-        self.__fset = fset
-        return self
-
-    def deleter(self, fdel: typing.Optional[typing.Callable[[typing.Any], None]]) -> "AdvancedProperty":
-        """Descriptor to change the deleter on a property.
-
-        :param fdel: New deleter.
-        :type fdel: typing.Optional[typing.Callable[[typing.Any, ], None]]
-        :return: AdvancedProperty
-        :rtype: AdvancedProperty
-        """
-        self.__fdel = fdel
-        return self
-
     def cgetter(self, fcget: typing.Optional[typing.Callable[[typing.Any], typing.Any]]) -> "AdvancedProperty":
         """Descriptor to change the class wide getter on a property.