Support : "webhook redelivery" (#385)

News
https://developers.line.biz/ja/news/2022/04/19/webhook-redelivery/

Added to two common properties
- create `DeliveryContext` class
- add two properties in `Event`
- add test case in `TestWebhookParser`

Author: nanato12

linebot/models/delivery_context.py

@@ -0,0 +1,34 @@
+#  Licensed under the Apache License, Version 2.0 (the "License"); you may
+#  not use this file except in compliance with the License. You may obtain
+#  a copy of the License at
+#
+#       https://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#  License for the specific language governing permissions and limitations
+#  under the License.
+
+"""linebot.models.delivery_context module."""
+
+
+from abc import ABCMeta
+
+from future.utils import with_metaclass
+
+from .base import Base
+
+
+class DeliveryContext(with_metaclass(ABCMeta, Base)):
+    """Abstract Base Class of DeliveryContext."""
+
+    def __init__(self, is_redelivery=None, **kwargs):
+        """__init__ method.
+
+        :param bool is_redelivery: Whether the webhook event is a redelivered one or not
+        :param kwargs:
+        """
+        super(DeliveryContext, self).__init__(**kwargs)
+
+        self.is_redelivery = is_redelivery

linebot/models/events.py

@@ -20,6 +20,7 @@
 from future.utils import with_metaclass
 
 from linebot.models.base import Base
+from linebot.models.delivery_context import DeliveryContext
 from linebot.models.messages import (
     TextMessage,
     ImageMessage,
@@ -46,7 +47,15 @@ class Event(with_metaclass(ABCMeta, Base)):
     https://developers.line.biz/en/reference/messaging-api/#webhook-event-objects
     """
 
-    def __init__(self, mode=None, timestamp=None, source=None, **kwargs):
+    def __init__(
+        self,
+        mode=None,
+        timestamp=None,
+        source=None,
+        webhook_event_id=None,
+        delivery_context=None,
+        **kwargs
+    ):
         """__init__ method.
 
         :param str mode: Channel state
@@ -67,6 +76,10 @@ def __init__(self, mode=None, timestamp=None, source=None, **kwargs):
                 'room': SourceRoom,
             }
         )
+        self.webhook_event_id = webhook_event_id
+        self.delivery_context = self.get_or_new_from_json_dict(
+            delivery_context, DeliveryContext
+        )
 
 
 class MessageEvent(Event):