io.BytesIO

clientDll.py

import io
import base64
import requests
import onnxruntime as ort
from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
from cryptography.hazmat.backends import default_backend

SERVER_URL = "http://127.0.0.1:8000"

def decrypt_data(encryptedModel, decryptKey) -> bytes:
    if isinstance(decryptKey, str):
        decryptKey = decryptKey.encode('utf-8')
        
    data = base64.b64decode(encryptedModel)
    iv, tag, encrypted = data[:16], data[16:32], data[32:]
    cipher = Cipher(algorithms.AES(decryptKey), modes.GCM(iv, tag), backend=default_backend())
    decryptor = cipher.decryptor()
    return decryptor.update(encrypted) + decryptor.finalize()

def getModel(decryptKey, apiKey, onnxConfig, modelName):
    payload_decrypt_str = {"apiKey": apiKey, "decryptKey": decryptKey, "modelName": modelName}
    resp = requests.post(f"{SERVER_URL}/getEncryptedModel", json=payload_decrypt_str)
    
    if resp.status_code != 200:
        raise RuntimeError(f"Erro ao buscar modelo do servidor: {resp.json().get('detail')}")
        
    encryptedModel = resp.json().get("data")
    decrypted_data = decrypt_data(encryptedModel, decryptKey)
    
    model_io = io.BytesIO(decrypted_data)
    
    session = ort.InferenceSession(model_io.getvalue(), onnxConfig)
    return session  # Disponível para o cliente no script principal como dll.getModel(...)