""" FastAPI backend for LionGuard moderation """ from fastapi import FastAPI, HTTPException from fastapi.staticfiles import StaticFiles from fastapi.responses import FileResponse from fastapi.middleware.cors import CORSMiddleware import os from typing import List from models import ( ModerateRequest, ModerateResponse, FeedbackRequest, FeedbackResponse, ChatRequest, ChatResponse, CategoryScore, ChatHistories, ) from services import ( analyze_text, submit_feedback, process_chat_message, ) app = FastAPI( title="LionGuard API", description="Multilingual moderation and guardrail comparison", version="2.0.0" ) # Enable CORS for development app.add_middleware( CORSMiddleware, allow_origins=["*"], allow_credentials=True, allow_methods=["*"], allow_headers=["*"], ) # Get the path to frontend directory FRONTEND_DIR = os.path.join(os.path.dirname(__file__), "../frontend") @app.post("/moderate", response_model=ModerateResponse) async def moderate_text(request: ModerateRequest): """ Analyze text for moderation risks using LionGuard models """ try: result = analyze_text(request.text, request.model) return ModerateResponse(**result) except Exception as e: raise HTTPException(status_code=500, detail=f"Error analyzing text: {str(e)}") @app.post("/send_feedback", response_model=FeedbackResponse) async def send_feedback(request: FeedbackRequest): """ Submit user feedback on moderation result """ try: result = submit_feedback(request.text_id, request.agree) return FeedbackResponse(**result) except Exception as e: raise HTTPException(status_code=500, detail=f"Error submitting feedback: {str(e)}") @app.post("/chat", response_model=ChatResponse) async def chat_comparison(request: ChatRequest): """ Compare guardrails across three approaches: - No moderation - OpenAI moderation - LionGuard moderation """ try: # Convert request histories to list of dicts history_no_mod = [msg.dict() for msg in request.histories.no_moderation] history_openai = [msg.dict() for msg in request.histories.openai_moderation] history_lg = [msg.dict() for msg in request.histories.lionguard] # Process message updated_no_mod, updated_openai, updated_lg, lg_score = await process_chat_message( request.message, request.model, history_no_mod, history_openai, history_lg ) # Convert back to response format return ChatResponse( histories=ChatHistories( no_moderation=updated_no_mod, openai_moderation=updated_openai, lionguard=updated_lg ), lionguard_score=lg_score ) except Exception as e: raise HTTPException(status_code=500, detail=f"Error processing chat: {str(e)}") # Serve static frontend files app.mount("/static", StaticFiles(directory=FRONTEND_DIR), name="static") @app.get("/") async def serve_frontend(): """ Serve the main HTML page """ index_path = os.path.join(FRONTEND_DIR, "index.html") if os.path.exists(index_path): return FileResponse(index_path) raise HTTPException(status_code=404, detail="Frontend not found") @app.get("/health") async def health_check(): """ Health check endpoint """ return {"status": "healthy", "service": "lionguard-api"} if __name__ == "__main__": import uvicorn uvicorn.run(app, host="0.0.0.0", port=8000)