server/server.py

from fastapi import FastAPI, HTTPException, Request
from fastapi.middleware.cors import CORSMiddleware
from fastapi.staticfiles import StaticFiles
from fastapi.responses import FileResponse
from apscheduler.schedulers.background import BackgroundScheduler
from datetime import datetime
import os
from dotenv import load_dotenv
from huggingface_hub import HfApi
import json
import logging

# Configure logging
logging.basicConfig(
    level=logging.INFO,
    format='%(asctime)s - %(levelname)s - %(message)s'
)

# Load environment variables
load_dotenv()

# API configuration
API_HOST = os.getenv("API_HOST", "0.0.0.0")
API_PORT = int(os.getenv("API_PORT", "3002"))

app = FastAPI()

# Add CORS middleware
app.add_middleware(
    CORSMiddleware,
    allow_origins=[
        "http://localhost:5173",  # Vite dev server
        f"http://localhost:{API_PORT}",  # API port
        "https://huggingface.co",  # HF main domain
        "https://*.hf.space",      # HF Spaces domains
    ],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# Cache storage
cache = {
    "data": None,
    "last_updated": None
}

# HF API configuration
HF_TOKEN = os.getenv("HUGGING_FACE_HUB_TOKEN")
REPO_ID = os.getenv("HUGGING_FACE_STORAGE_REPO")
FILE_PATH = os.getenv("HUGGING_FACE_STORAGE_FILE_PATH")
CACHE_DURATION_MINUTES = int(os.getenv("UPDATE_INTERVAL_MINUTES", "15"))

# Initialize HF API client
hf_api = HfApi(token=HF_TOKEN)

def fetch_leaderboards():
    """Fetch leaderboards data from Hugging Face"""
    try:
        logging.info(f"Fetching leaderboards from {REPO_ID}/{FILE_PATH}")
        # Download the JSON file directly with force_download to ensure we get the latest version
        json_path = hf_api.hf_hub_download(
            repo_id=REPO_ID,
            filename=FILE_PATH,
            repo_type="dataset",
            force_download=True,  # Force download to ensure we get the latest version
            force_filename="leaderboards_latest.json"  # Force a specific filename to avoid caching issues
        )
        
        logging.info(f"File downloaded to: {json_path}")
        
        with open(json_path, 'r') as f:
            new_data = json.load(f)
            old_data = cache["data"]
            cache["data"] = new_data
            cache["last_updated"] = datetime.now()
            
            # Log the differences
            old_len = len(old_data) if old_data and isinstance(old_data, list) else 0
            new_len = len(new_data) if isinstance(new_data, list) else 0
            logging.info(f"Cache updated: Old entries: {old_len}, New entries: {new_len}")
            logging.info(f"Cache update timestamp: {cache['last_updated']}")
            
    except Exception as e:
        logging.error(f"Error fetching data: {str(e)}", exc_info=True)
        if not cache["data"]:  # Only raise if we don't have any cached data
            raise HTTPException(status_code=500, detail="Failed to fetch leaderboards data")

# Initial fetch
fetch_leaderboards()

@app.get("/api/leaderboards")
async def get_leaderboards():
    """Get leaderboards data from cache"""
    if not cache["data"]:
        fetch_leaderboards()
    
    return {
        "data": cache["data"],
        "last_updated": cache["last_updated"].isoformat() if cache["last_updated"] else None
    }

@app.get("/api/health")
async def health_check():
    """Health check endpoint"""
    return {
        "status": "healthy",
        "cache_status": "initialized" if cache["data"] else "empty",
        "last_updated": cache["last_updated"].isoformat() if cache["last_updated"] else None
    }

@app.post("/api/webhook")
async def handle_webhook(request: Request):
    """Handle webhook notifications from Hugging Face Hub"""
    try:
        body = await request.json()
        logging.info(f"Received webhook with payload: {body}")
        
        # Get the event details
        event = body.get("event", {})
        
        # Verify if it's a relevant update (repo content update)
        if event.get("action") == "update" and event.get("scope") == "repo.content":
            try:
                logging.info(f"Dataset update detected for repo {REPO_ID}, file {FILE_PATH}")
                # Force a clean fetch
                fetch_leaderboards()
                if cache["last_updated"]:
                    logging.info(f"Cache successfully updated at {cache['last_updated']}")
                    return {"status": "success", "message": "Cache updated"}
                else:
                    logging.error("Cache update failed: last_updated is None")
                    return {"status": "error", "message": "Cache update failed"}
            except Exception as fetch_error:
                logging.error(f"Error during fetch_leaderboards: {str(fetch_error)}", exc_info=True)
                return {"status": "error", "message": f"Failed to update cache: {str(fetch_error)}"}
        
        logging.info(f"Ignoring webhook event: action={event.get('action')}, scope={event.get('scope')}")
        return {"status": "ignored", "message": "Event type not relevant"}
        
    except Exception as e:
        logging.error(f"Error processing webhook: {str(e)}", exc_info=True)
        raise HTTPException(status_code=500, detail=f"Failed to process webhook: {str(e)}")

# Mount static files for the React client
app.mount("/", StaticFiles(directory="static", html=True), name="static")

if __name__ == "__main__":
    import uvicorn
    uvicorn.run("server:app", host=API_HOST, port=API_PORT, reload=True)