Add serialise to base components, and remove fields on media items that are receive only

Author: muddyfish

discord/components.py

@@ -163,6 +163,9 @@ def _raw_construct(cls, **kwargs) -> Self:
     def to_dict(self) -> ComponentBasePayload:
         raise NotImplementedError
 
+    async def serialise(self, ctx) -> ComponentBasePayload:
+        return self.to_dict()
+
 
 class ActionRow(Component):
     """Represents a Discord Bot UI Kit Action Row.
@@ -963,13 +966,13 @@ def _from_data(cls, data: UnfurledMediaItemPayload, state: Optional[ConnectionSt
         return self
 
     def _update(self, data: UnfurledMediaItemPayload, state: Optional[ConnectionState]) -> None:
-        self.proxy_url = data['proxy_url']
+        self.proxy_url = data.get('proxy_url')
         self.height = data.get('height')
         self.width = data.get('width')
         self.content_type = data.get('content_type')
         self._flags = data.get('flags', 0)
         self.placeholder = data.get('placeholder')
-        self.loading_state = try_enum(MediaItemLoadingState, data['loading_state'])
+        self.loading_state = try_enum(MediaItemLoadingState, data.get('loading_state'))
         self._state = state
 
     def __repr__(self) -> str: