feat: clear message event (#789)

Author: dazy-ds

packages/ragbits-chat/CHANGELOG.md

@@ -1,6 +1,7 @@
 # CHANGELOG
 
 ## Unreleased
+- Add `clear_message` event type allowing to reset whole message (#789)
 - Add authentication handling in the UI (#763)
 - Add backend authentication (#761)
 

packages/ragbits-chat/src/ragbits/chat/api.py

@@ -541,7 +541,7 @@ async def _chat_response_to_sse(
                     {
                         "type": response.type.value,
                         "content": response.content
-                        if isinstance(response.content, str | list)
+                        if isinstance(response.content, str | list | None)
                         else response.content.model_dump(),
                     }
                 )

packages/ragbits-chat/src/ragbits/chat/interface/_interface.py

@@ -236,6 +236,11 @@ def create_image_response(image_id: str, image_url: str) -> ChatResponse:
         """Helper method to create an image response."""
         return ChatResponse(type=ChatResponseType.IMAGE, content=Image(id=image_id, url=image_url))
 
+    @staticmethod
+    def create_clear_message_response() -> ChatResponse:
+        """Helper method to create an clear message response."""
+        return ChatResponse(type=ChatResponseType.CLEAR_MESSAGE, content=None)
+
     @staticmethod
     def _sign_state(state: dict[str, Any]) -> str:
         """

packages/ragbits-chat/src/ragbits/chat/interface/types.py

@@ -77,6 +77,7 @@ class ChatResponseType(str, Enum):
     LIVE_UPDATE = "live_update"
     FOLLOWUP_MESSAGES = "followup_messages"
     IMAGE = "image"
+    CLEAR_MESSAGE = "clear_message"
 
 
 class ChatContext(BaseModel):
@@ -93,7 +94,7 @@ class ChatResponse(BaseModel):
     """Container for different types of chat responses."""
 
     type: ChatResponseType
-    content: str | Reference | StateUpdate | LiveUpdate | list[str] | Image
+    content: str | Reference | StateUpdate | LiveUpdate | list[str] | Image | None
 
     def as_text(self) -> str | None:
         """
@@ -157,6 +158,12 @@ def as_image(self) -> Image | None:
         """
         return cast(Image, self.content) if self.type == ChatResponseType.IMAGE else None
 
+    def as_clear_message(self) -> None:
+        """
+        Return the content of clear_message response, which is None
+        """
+        return cast(None, self.content)
+
 
 class ChatMessageRequest(BaseModel):
     """Client-side chat request interface."""