refactor: use classmethods

Signed-off-by: Alexander Tkachev <sasha64sasha@gmail.com>

cloudevents/abstract/event.py

@@ -25,8 +25,8 @@ class CloudEvent:
         """
         raise NotImplementedError()
 
-    @property
+    @classmethod
-    def attributes(self) -> typing.Dict[str, typing.Any]:
+    def get_attributes(cls, event: "CloudEvent") -> typing.Dict[str, typing.Any]:
         """
         :return: Attributes of this event.
 
@@ -35,8 +35,8 @@ class CloudEvent:
         """
         raise NotImplementedError()
 
-    @property
+    @classmethod
-    def data(self) -> typing.Optional[typing.Any]:
+    def get_data(cls, event: "CloudEvent") -> typing.Optional[typing.Any]:
         """
         :return: Data value of the  event.
         You MUST NOT mutate this dict.
@@ -46,7 +46,9 @@ class CloudEvent:
 
     def __eq__(self, other: typing.Any) -> bool:
         if isinstance(other, CloudEvent):
-            return self.data == other.data and self.attributes == other.attributes
+            same_data = self.get_data(self) == other.get_data(other)
+            same_attributes = self.get_attributes(self) == other.get_attributes(other)
+            return same_data and same_attributes
         return False
 
     def __getitem__(self, key: str) -> typing.Any:
@@ -56,7 +58,7 @@ class CloudEvent:
         :param key: The event attribute name.
         :return: The event attribute value.
         """
-        return self.attributes[key]
+        return self.get_attributes(self)[key]
 
     def get(
         self, key: str, default: typing.Optional[typing.Any] = None
@@ -72,19 +74,21 @@ class CloudEvent:
             no attribute with the given key exists.
         :returns: The event attribute value if exists, default value otherwise.
         """
-        return self.attributes.get(key, default)
+        return self.get_attributes(self).get(key, default)
 
     def __iter__(self) -> typing.Iterator[typing.Any]:
-        return iter(self.attributes)
+        return iter(self.get_attributes(self))
 
     def __len__(self) -> int:
-        return len(self.attributes)
+        return len(self.get_attributes(self))
 
     def __contains__(self, key: str) -> bool:
-        return key in self.attributes
+        return key in self.get_attributes(self)
 
     def __repr__(self) -> str:
-        return str({"attributes": self.attributes, "data": self.data})
+        return str(
+            {"attributes": self.get_attributes(self), "data": self.get_data(self)}
+        )
 
 
 AnyCloudEvent = TypeVar("AnyCloudEvent", bound=CloudEvent)

cloudevents/http/event.py

@@ -52,7 +52,7 @@ class CloudEvent(abstract.CloudEvent):
         :type data: typing.Any
         """
         self._attributes = {k.lower(): v for k, v in attributes.items()}
-        self._data = data
+        self.data = data
         if "specversion" not in self._attributes:
             self._attributes["specversion"] = "1.0"
         if "id" not in self._attributes:
@@ -74,21 +74,13 @@ class CloudEvent(abstract.CloudEvent):
                 f"Missing required keys: {required_set - self._attributes.keys()}"
             )
 
-    @property
+    @classmethod
-    def attributes(self) -> typing.Dict[str, typing.Any]:
+    def get_attributes(cls, event: "CloudEvent") -> typing.Dict[str, typing.Any]:
-        return self._attributes
+        return event._attributes
 
-    @property
+    @classmethod
-    def data(self) -> typing.Optional[typing.Any]:
+    def get_data(cls, event: "CloudEvent") -> typing.Optional[typing.Any]:
-        return self._data
+        return event.data
-
-    @data.setter
-    def data(self, value) -> None:
-        """
-        Exists for backwards compatibility
-        :param value: new data vale
-        """
-        self._data = value
 
     def __setitem__(self, key: str, value: typing.Any) -> None:
         self._attributes[key] = value

cloudevents/tests/test_abstract_cloudevent.py

@@ -16,7 +16,7 @@ def test_data_is_abstract():
     exists mainly for coverage reasons
     """
     with pytest.raises(NotImplementedError):
-        CloudEvent().data
+        CloudEvent.get_data(CloudEvent())
 
 
 def test_attributes_is_abstract():
@@ -24,4 +24,4 @@ def test_attributes_is_abstract():
     exists mainly for coverage reasons
     """
     with pytest.raises(NotImplementedError):
-        CloudEvent().attributes
+        CloudEvent.get_attributes(CloudEvent())