Using RPyC and property decorator to set a value via a setter method on remote host

[CryptoMathician]

Hi,

I want to use RPyC to access properties of a class from the remote host, but when I try to get it work only the getter is working correctly and the setter not. Here the details:

Server.py

import rpyc
from rpyc.utils.server import ThreadedServer


@rpyc.service
class MyService(rpyc.Service):
    def __init__(self):
        self._x = 10
        self._y = 2

    @property
    def x(self) -> int:
        return self._x

    @x.setter
    def x(self, v: int) -> None:
        self._x = v

    @property
    def y(self) -> int:
        return self._y

    @y.setter
    def y(self, v: int) -> None:
        self._y = v


def main():
    t = ThreadedServer(MyService, port=8000, protocol_config={
        "allow_all_attrs": True,
        "allow_setattr": True,
        "allow_delattr": True
    })
    print("Listening on port 8000...")
    t.start()


if __name__ == "__main__":
    main()

Client.py

import rpyc


def main():
    c = rpyc.connect("localhost", 8000)
    x = c.root.x
    print(f"x: {x}\ttype: {type(x)}")
    print(dir(c.root))
    c.root.x = 42


if __name__ == "__main__":
    main()

# Example: https://stackoverflow.com/questions/34844127/using-rpyc-to-update-properties-on-a-remote-object

The expected result is that I am able to set the property x of the remote object MyService.
However, I get a different result. This is the output of the "Client.py":

x: 10	type: <class 'int'>
['ALIASES', '__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__le__', '__lt__', '__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__slots__', '__str__', '__subclasshook__', '__weakref__', '_connect', '_protocol', '_rpyc_delattr', '_rpyc_setattr', '_x', '_y', 'exposed_get_service_aliases', 'exposed_get_service_name', 'get_service_aliases', 'get_service_name', 'on_connect', 'on_disconnect', 'x', 'y']
Traceback (most recent call last):
  File "<path>\Client.py", line 13, in <module>
    main()
  File "<path>\Client.py", line 9, in main
    c.root.x = 42
  File "<path>\venv\lib\site-packages\rpyc\core\netref.py", line 165, in __setattr__
    syncreq(self, consts.HANDLE_SETATTR, name, value)
  File "<path>\venv\lib\site-packages\rpyc\core\netref.py", line 63, in syncreq
    return conn.sync_request(handler, proxy, *args)
  File "<path>\venv\lib\site-packages\rpyc\core\protocol.py", line 490, in sync_request
    return _async_res.value
  File "<path>\venv\lib\site-packages\rpyc\core\async_.py", line 108, in value
    raise self._obj
_get_exception_class.<locals>.Derived: access denied

========= Remote Traceback (1) =========
Traceback (most recent call last):
  File "<path>\venv\lib\site-packages\rpyc\core\protocol.py", line 324, in _dispatch_request
    res = self._HANDLERS[handler](self, *args)
  File "<path>\venv\lib\site-packages\rpyc\core\protocol.py", line 631, in _handle_setattr
    return self._access_attr(obj, name, (value,), "_rpyc_setattr", "allow_setattr", setattr)
  File "<path>\venv\lib\site-packages\rpyc\core\protocol.py", line 553, in _access_attr
    return accessor(obj, name, *args)
  File "<path>\venv\lib\site-packages\rpyc\core\service.py", line 75, in _rpyc_setattr
    raise AttributeError("access denied")
AttributeError: access denied

I am using a virtual environment with the following pyvenv.cfg:

home = C:\Program Files\Python310
implementation = CPython
version_info = 3.10.4.final.0
virtualenv = 20.4.7
include-system-site-packages = false
base-prefix = C:\Program Files\Python310
base-exec-prefix = C:\Program Files\Python310
base-executable = C:\Program Files\Python310\python.exe

RPyC version: 5.2.1
Python Version: 3.10
Operatin System: Windows 10

To reproduce the error run the "Server.py" and then the "Client.py".

The documentation Link and Link didn't helped me.

I would appreciate you, when you are able to help.

[CryptoMathician]

Maybe as an additional comment.
I don't want to use the magic methods to set the value.
It would be nice to have it work out of the box like it should work.

[comrumino]

Hm. Odd behavior. I'll have to dig in more when I have time. This behavior is not unique to the new decorators from what I can tell at first glance.

[CryptoMathician]

Thank you! Let me know when I am able to help you regarding this topic.

[achrafka]

Because there is two methods in Service class _rpyc_delattr and _rpyc_setattr which they raise AttributeError i guess it's about security implications