proxy.py

from fastapi import FastAPI, Request, HTTPException, Depends
from fastapi.responses import JSONResponse
import httpx
import jwt
import os

app = FastAPI()

# Backend servis URL'leri
SERVICES = {
    'users': 'https://users-service.com',
    'products': 'https://products-service.com',
    'orders': 'https://orders-service.com'
}

# JWT Doğrulama
async def verify_token(request: Request):
    auth_header = request.headers.get('Authorization')
    
    if not auth_header or not auth_header.startswith('Bearer '):
        raise HTTPException(status_code=401, detail='Missing token')
    
    token = auth_header.replace('Bearer ', '')
    
    try:
        decoded = jwt.decode(token, os.environ['JWT_SECRET'], algorithms=['HS256'])
        return decoded
    except jwt.ExpiredSignatureError:
        raise HTTPException(status_code=401, detail='Token expired')
    except jwt.InvalidTokenError:
        raise HTTPException(status_code=401, detail='Invalid token')

# Proxy tüm requestleri backend'e yönlendir
@app.api_route("/{service}/{path:path}", methods=["GET", "POST", "PUT", "DELETE"])
async def gateway_proxy(
    service: str,
    path: str,
    request: Request,
    user: dict = Depends(verify_token)
):
    # Servis kontrolü
    if service not in SERVICES:
        raise HTTPException(status_code=404, detail='Service not found')
    
    # Backend URL oluştur
    backend_url = f"{SERVICES[service]}/{path}"
    
    # Request body'yi al
    body = await request.body()
    
    # Headers'ı hazırla (user bilgisi ekle)
    headers = dict(request.headers)
    headers['X-User-Id'] = str(user['user_id'])
    headers['X-User-Email'] = user['email']
    
    # Backend'e istek at
    async with httpx.AsyncClient() as client:
        try:
            response = await client.request(
                method=request.method,
                url=backend_url,
                content=body,
                headers=headers,
                params=request.query_params
            )
            
            return JSONResponse(
                content=response.json(),
                status_code=response.status_code
            )
        except Exception as e:
            raise HTTPException(status_code=502, detail=f'Backend error: {str(e)}')

# Public endpoints (auth gerektirmeyen)
@app.post("/auth/login")
async def login(request: Request):
    body = await request.json()
    
    # Kullanıcı doğrulama (database)
    # ... user verification logic
    
    # JWT üret
    token = jwt.encode(
        {
            'user_id': 123,
            'email': body['email'],
            'exp': datetime.utcnow() + timedelta(hours=1)
        },
        os.environ['JWT_SECRET'],
        algorithm='HS256'
    )
    
    return {'token': token}

@app.get("/health")
async def health():
    return {'status': 'ok'}