| import os |
| from contextlib import asynccontextmanager |
|
|
| from dotenv import load_dotenv |
| from fastapi import FastAPI, HTTPException, Request |
| from fastapi.concurrency import run_in_threadpool |
| from fastapi.responses import StreamingResponse |
| from pydantic import BaseModel, Field |
|
|
| import langchain |
|
|
| from core.config import Settings |
| from core.graph_builder import build_financial_graph |
| from core.runner import create_llm, run_financial_query, astream_financial_query |
|
|
|
|
| @asynccontextmanager |
| async def lifespan(app: FastAPI): |
| load_dotenv() |
| langchain.debug = os.getenv("LANGCHAIN_DEBUG", "").lower() in ("1", "true", "yes") |
| settings = Settings() |
| llm = create_llm(settings) |
| app.state.settings = settings |
| app.state.graph = build_financial_graph(llm) |
| yield |
|
|
|
|
| app = FastAPI(title="FinAgent", lifespan=lifespan) |
|
|
|
|
| class ChatRequest(BaseModel): |
| query: str = Field(..., min_length=1, max_length=16000) |
|
|
|
|
| class StepOut(BaseModel): |
| node: str |
| content: str |
| step_latency: float | None = None |
| total_latency: float | None = None |
|
|
|
|
| class ChatResponse(BaseModel): |
| memo: str | None = None |
| steps: list[StepOut] = Field(default_factory=list) |
| total_latency: float | None = None |
|
|
|
|
| @app.get("/health") |
| def health(): |
| return {"status": "ok"} |
|
|
|
|
| @app.post("/chat", response_model=ChatResponse) |
| async def chat(request: Request, body: ChatRequest): |
| graph = request.app.state.graph |
| q = body.query.strip() |
| if not q: |
| raise HTTPException(status_code=400, detail="query must not be empty") |
| try: |
| result = await run_in_threadpool(run_financial_query, graph, q) |
| except Exception as e: |
| raise HTTPException(status_code=503, detail=str(e)) from e |
| return ChatResponse(**result) |
|
|
|
|
| @app.post("/chat/stream") |
| async def chat_stream(request: Request, body: ChatRequest): |
| graph = request.app.state.graph |
| q = body.query.strip() |
| if not q: |
| raise HTTPException(status_code=400, detail="query must not be empty") |
| |
| return StreamingResponse( |
| astream_financial_query(graph, q), |
| media_type="text/event-stream" |
| ) |
|
|
