UE 5.5+ Python plugin uobject classes not reflected

Development Pipeline & Plugins Plugins
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Hi Community and Devs,

I was wondering if anyone else has been using UE5.5+ with Remote Control and calling Python UObjects?

In 5.3 and 5.4 we had uobject python classes that were getting there functions called remotely and everything worked perfectly. Since 5.5+ that has been broken ( I have also built the latest source 5.7 and it looks to still not work).

I came across this ticket Unreal Engine Issues and Bug Tracker (UE-247331) that outlines the same issue and it mentions that is has been fixed, but in my plugin scenario still fails.

Reproduction steps

  1. Create a UE Plugin, and in Contents\Python create a .py file with the following content
import unreal


@unreal.uclass()
class PyRemoteDebug(unreal.BlueprintFunctionLibrary):
# class PyRemoteDebug(unreal.Object): # also tested inheriting from Object, but made no difference

    @unreal.ufunction(
        params=[str],
        ret=bool,
        static=True,
        meta=dict(Category="PythonRemoteDebugging")
    )
    def check_check_123(name:str):
        """
        Simple log method to check the command is getting triggered
        """

        unreal.log(f"This is working, {name}!")
        return True
  1. Make sure the plugin requires Remote Control and Python development plugin
  2. In Postman ( I used it for the quickest test turn around)
    • Set the request to PUT to the following address 127.0.0.1:30010/remote/object/call
    • Set the Body to raw and the payload to
{
    "objectPath":"/Engine/PythonTypes.Default__PyRemoteDebug",
    "functionName":"check_check_123",
    "parameters":
        {
            "name":"Developer"
        },
    "generateTransaction":true
}

Result: In unreal it will log that the Python type does not exist, but you can manually call the code using the command line.

LogRemoteControl: Error: Web Remote Call deserialization error: Object: /Engine/PythonTypes.Default__PyRemoteDebug does not exist.

I am not sure if something has changed with how one is meant to structure python classes that want to be utilised in unreal as uobjects, or if the fix mentioned in UE-247331 might have not taken this scenario into account.

Any help would be greatly appreciated :slight_smile: