add send-message-simple-with-history endpoint to avoid… (#2101)

* add send-message-simple-with-history endpoint to support ramp. avoids bad json output in models and allows client to pass history in instead of maintaining it in our own session

* slightly better error checking

* addressing code review

* reject on any empty message

* update test naming

backend/ee/danswer/server/query_and_chat/chat_backend.py

@@ -8,18 +8,31 @@ from sqlalchemy.orm import Session
 from danswer.auth.users import current_user
 from danswer.chat.chat_utils import create_chat_chain
 from danswer.chat.models import DanswerAnswerPiece
+from danswer.chat.models import LLMRelevanceFilterResponse
 from danswer.chat.models import QADocsResponse
 from danswer.chat.models import StreamingError
 from danswer.chat.process_message import stream_chat_message_objects
+from danswer.configs.constants import MessageType
+from danswer.configs.danswerbot_configs import DANSWER_BOT_TARGET_CHUNK_PERCENTAGE
+from danswer.db.chat import create_chat_session
+from danswer.db.chat import create_new_chat_message
 from danswer.db.chat import get_or_create_root_message
 from danswer.db.engine import get_session
 from danswer.db.models import User
+from danswer.llm.factory import get_llms_for_persona
+from danswer.llm.utils import get_max_input_tokens
+from danswer.natural_language_processing.utils import get_tokenizer
+from danswer.one_shot_answer.qa_utils import combine_message_thread
 from danswer.search.models import OptionalSearchSetting
 from danswer.search.models import RetrievalDetails
+from danswer.secondary_llm_flows.query_expansion import thread_based_query_rephrase
 from danswer.server.query_and_chat.models import ChatMessageDetail
 from danswer.server.query_and_chat.models import CreateChatMessageRequest
 from danswer.utils.logger import setup_logger
 from ee.danswer.server.query_and_chat.models import BasicCreateChatMessageRequest
+from ee.danswer.server.query_and_chat.models import (
+    BasicCreateChatMessageWithHistoryRequest,
+)
 from ee.danswer.server.query_and_chat.models import ChatBasicResponse
 from ee.danswer.server.query_and_chat.models import SimpleDoc
 
@@ -122,3 +135,131 @@ def handle_simplified_chat_message(
         response.answer_citationless = remove_answer_citations(answer)
 
     return response
+
+
+@router.post("/send-message-simple-with-history")
+def handle_send_message_simple_with_history(
+    req: BasicCreateChatMessageWithHistoryRequest,
+    user: User | None = Depends(current_user),
+    db_session: Session = Depends(get_session),
+) -> ChatBasicResponse:
+    """This is a Non-Streaming version that only gives back a minimal set of information.
+    takes in chat history maintained by the caller
+    and does query rephrasing similar to answer-with-quote"""
+
+    if len(req.messages) == 0:
+        raise HTTPException(status_code=400, detail="Messages cannot be zero length")
+
+    expected_role = MessageType.USER
+    for msg in req.messages:
+        if not msg.message:
+            raise HTTPException(
+                status_code=400, detail="One or more chat messages were empty"
+            )
+
+        if msg.role != expected_role:
+            raise HTTPException(
+                status_code=400,
+                detail="Message roles must start and end with MessageType.USER and alternate in-between.",
+            )
+        if expected_role == MessageType.USER:
+            expected_role = MessageType.ASSISTANT
+        else:
+            expected_role = MessageType.USER
+
+    query = req.messages[-1].message
+    msg_history = req.messages[:-1]
+
+    logger.info(f"Received new simple with history chat message: {query}")
+
+    user_id = user.id if user is not None else None
+    chat_session = create_chat_session(
+        db_session=db_session,
+        description="handle_send_message_simple_with_history",
+        user_id=user_id,
+        persona_id=req.persona_id,
+        one_shot=False,
+    )
+
+    llm, _ = get_llms_for_persona(persona=chat_session.persona)
+
+    llm_tokenizer = get_tokenizer(
+        model_name=llm.config.model_name,
+        provider_type=llm.config.model_provider,
+    )
+
+    input_tokens = get_max_input_tokens(
+        model_name=llm.config.model_name, model_provider=llm.config.model_provider
+    )
+    max_history_tokens = int(input_tokens * DANSWER_BOT_TARGET_CHUNK_PERCENTAGE)
+
+    # Every chat Session begins with an empty root message
+    root_message = get_or_create_root_message(
+        chat_session_id=chat_session.id, db_session=db_session
+    )
+
+    chat_message = root_message
+    for msg in msg_history:
+        chat_message = create_new_chat_message(
+            chat_session_id=chat_session.id,
+            parent_message=chat_message,
+            prompt_id=req.prompt_id,
+            message=msg.message,
+            token_count=len(llm_tokenizer.encode(msg.message)),
+            message_type=msg.role,
+            db_session=db_session,
+            commit=False,
+        )
+    db_session.commit()
+
+    history_str = combine_message_thread(
+        messages=msg_history,
+        max_tokens=max_history_tokens,
+        llm_tokenizer=llm_tokenizer,
+    )
+
+    rephrased_query = req.query_override or thread_based_query_rephrase(
+        user_query=query,
+        history_str=history_str,
+    )
+
+    full_chat_msg_info = CreateChatMessageRequest(
+        chat_session_id=chat_session.id,
+        parent_message_id=chat_message.id,
+        message=rephrased_query,
+        file_descriptors=[],
+        prompt_id=req.prompt_id,
+        search_doc_ids=None,
+        retrieval_options=req.retrieval_options,
+        query_override=rephrased_query,
+        chunks_above=req.chunks_above,
+        chunks_below=req.chunks_below,
+        full_doc=req.full_doc,
+    )
+
+    packets = stream_chat_message_objects(
+        new_msg_req=full_chat_msg_info,
+        user=user,
+        db_session=db_session,
+    )
+
+    response = ChatBasicResponse()
+
+    answer = ""
+    for packet in packets:
+        if isinstance(packet, DanswerAnswerPiece) and packet.answer_piece:
+            answer += packet.answer_piece
+        elif isinstance(packet, QADocsResponse):
+            response.simple_search_docs = translate_doc_response_to_simple_doc(packet)
+        elif isinstance(packet, StreamingError):
+            response.error_msg = packet.error
+        elif isinstance(packet, ChatMessageDetail):
+            response.message_id = packet.message_id
+        elif isinstance(packet, LLMRelevanceFilterResponse):
+            response.llm_chunks_indices = packet.relevant_chunk_indices
+
+    response.answer = answer
+    if answer:
+        response.answer_citationless = remove_answer_citations(answer)
+
+    return response

backend/ee/danswer/server/query_and_chat/models.py

@@ -1,6 +1,8 @@
 from pydantic import BaseModel
+from pydantic import Field
 
 from danswer.configs.constants import DocumentSource
+from danswer.one_shot_answer.models import ThreadMessage
 from danswer.search.enums import LLMEvaluationType
 from danswer.search.enums import SearchType
 from danswer.search.models import ChunkContext
@@ -45,6 +47,16 @@ class BasicCreateChatMessageRequest(ChunkContext):
     search_doc_ids: list[int] | None = None
 
 
+class BasicCreateChatMessageWithHistoryRequest(ChunkContext):
+    # Last element is the new query. All previous elements are historical context
+    messages: list[ThreadMessage]
+    prompt_id: int | None
+    persona_id: int
+    retrieval_options: RetrievalDetails = Field(default_factory=RetrievalDetails)
+    query_override: str | None = None
+    skip_rerank: bool | None = None
+
+
 class SimpleDoc(BaseModel):
     id: str
     semantic_identifier: str
@@ -61,3 +73,4 @@ class ChatBasicResponse(BaseModel):
     simple_search_docs: list[SimpleDoc] | None = None
     error_msg: str | None = None
     message_id: int | None = None
+    llm_chunks_indices: list[int] | None = None