web_socket.py

# backend/api/websocket.py
from fastapi import FastAPI, WebSocket, WebSocketDisconnect
from fastapi.middleware.cors import CORSMiddleware
import asyncio
import json
import cv2
import base64

app = FastAPI()

app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

@app.websocket("/ws/video")
async def video_websocket(websocket: WebSocket):
    await websocket.accept()
    
    # Initialize components
    detector = FaceDetector()
    recognizer = FaceRecognizer()
    attendance_manager = AttendanceManager(db_session)
    processor = VideoProcessor(detector, recognizer, attendance_manager)
    
    try:
        async for frame in processor.process_video():
            # Encode frame to JPEG
            _, buffer = cv2.imencode('.jpg', frame)
            frame_b64 = base64.b64encode(buffer).decode('utf-8')
            
            # Send to client
            await websocket.send_json({
                'frame': frame_b64,
                'timestamp': datetime.now().isoformat()
            })
            
    except WebSocketDisconnect:
        print("Client disconnected")

@app.get("/api/analytics/dashboard")
async def get_dashboard_data():
    """Get all dashboard metrics"""
    analytics = AnalyticsService(db_session)
    
    return {
        'personnel_present': analytics.get_personnel_present(),
        'shift_coverage': analytics.get_shift_coverage(),
        'staffing_trends': analytics.get_staffing_trends().to_dict(),
        'missing_personnel': [
            {'id': e.id, 'name': e.name} 
            for e in analytics.get_missing_personnel()
        ],
        'timestamp': datetime.now().isoformat()
    }