api.py

from __future__ import annotations

from pathlib import Path

from dotenv import load_dotenv
from fastapi import FastAPI
from pydantic import BaseModel

from crag import CRAGSettings, CorrectiveRAGPipeline


load_dotenv()

app = FastAPI(title="Corrective RAG API")
_pipeline: CorrectiveRAGPipeline | None = None


class AskRequest(BaseModel):
    question: str


def get_pipeline() -> CorrectiveRAGPipeline:
    global _pipeline
    if _pipeline is None:
        pdf_paths = sorted(Path("documents").glob("*.pdf"))
        settings = CRAGSettings(top_k=8, final_k=4, use_mmr=True)
        _pipeline = CorrectiveRAGPipeline.from_pdfs(pdf_paths, settings)
    return _pipeline


@app.get("/health")
def health() -> dict[str, str]:
    return {"status": "ok"}


@app.post("/ask")
def ask(request: AskRequest):
    result = get_pipeline().ask(request.question)
    return {
        "question": result.question,
        "answer": result.answer,
        "verdict": result.verdict,
        "reason": result.reason,
        "route": result.route,
        "sources": [source.__dict__ for source in result.sources],
        "candidate_scores": result.debug.get("candidate_scores", []),
    }