a9589bfc93
- "backend/chat_service.py" - "backend/routers/chat.py" - "backend/main.py" - "backend/tests/test_chat.py" GSD-Task: S03/T01
60 lines
1.8 KiB
Python
60 lines
1.8 KiB
Python
"""Chat endpoint — POST /api/v1/chat with SSE streaming response.
|
|
|
|
Accepts a query and optional creator filter, returns a Server-Sent Events
|
|
stream with sources, token, done, and error events.
|
|
"""
|
|
|
|
from __future__ import annotations
|
|
|
|
import logging
|
|
|
|
from fastapi import APIRouter, Depends
|
|
from fastapi.responses import StreamingResponse
|
|
from pydantic import BaseModel, Field
|
|
from sqlalchemy.ext.asyncio import AsyncSession
|
|
|
|
from chat_service import ChatService
|
|
from config import Settings, get_settings
|
|
from database import get_session
|
|
|
|
logger = logging.getLogger("chrysopedia.chat.router")
|
|
|
|
router = APIRouter(prefix="/chat", tags=["chat"])
|
|
|
|
|
|
class ChatRequest(BaseModel):
|
|
"""Request body for the chat endpoint."""
|
|
|
|
query: str = Field(..., min_length=1, max_length=1000)
|
|
creator: str | None = None
|
|
|
|
|
|
def _get_chat_service(settings: Settings = Depends(get_settings)) -> ChatService:
|
|
"""Build a ChatService from current settings."""
|
|
return ChatService(settings)
|
|
|
|
|
|
@router.post("")
|
|
async def chat(
|
|
body: ChatRequest,
|
|
db: AsyncSession = Depends(get_session),
|
|
service: ChatService = Depends(_get_chat_service),
|
|
) -> StreamingResponse:
|
|
"""Stream a chat response as Server-Sent Events.
|
|
|
|
SSE protocol:
|
|
- ``event: sources`` — citation metadata array (sent first)
|
|
- ``event: token`` — streamed text chunk (repeated)
|
|
- ``event: done`` — completion metadata with cascade_tier
|
|
- ``event: error`` — error message (on failure)
|
|
"""
|
|
logger.info("chat_request query=%r creator=%r", body.query, body.creator)
|
|
|
|
return StreamingResponse(
|
|
service.stream_response(query=body.query, db=db, creator=body.creator),
|
|
media_type="text/event-stream",
|
|
headers={
|
|
"Cache-Control": "no-cache",
|
|
"X-Accel-Buffering": "no",
|
|
},
|
|
)
|