Python bindings to facilitate PyCasbin-on-CPP

[EmperorYP7]

The project has the potential to utilize its C++ API for PyCasbin-on-CPP through Python bindings which will allow us to call C++ code from Python. CPython exposes various endpoints for us to make bindings, but this approach will be cumbersome and vulnerable to a lot of errors and memory leaks which won't be easy to debug. pybind11 can be used for making Python bindings and modules with C++11 as it is based on Boost::Python library.

[Zxilly]

Yes, this is our plan.
Before actually create the wrapper, we need to assure that casbin-cpp have all api of pycasbin.
Pycasbin on cpp will be regard as an optional high performance backend of pycasbin. But not a separate library.

[EmperorYP7]

@Zxilly I tried to make a boilerplate for the workflow to make these bindings and management of pybind11 module with CMake.
Here's the dev branch: https://github.com/EmperorYP7/casbin-cpp/tree/python-bindings kindly look at ./CMakeLists.txt and /ext/Findpybind11.cmake

Is it somewhat similar to what you envisioned for this?

[EmperorYP7]

Here's the dev branch: https://github.com/EmperorYP7/casbin-cpp/tree/python-bindings kindly look at ./CMakeLists.txt and /ext/Findpybind11.cmake

@hsluoyz @xcaptain is this approach feasible?

[Zxilly]

Good work.
You can create a Pull Request for this.

[hsluoyz]

@EmperorYP7 I don't know the detailed Py-Cpp binding techniques, but we want:

1. Compatible across all OS: Windows, Linux, macOS
2. Simple, modern
3. Good performance

[EmperorYP7]

@hsluoyz yes, the bindings will be cross-platform. The performance will be similar to the resultant of Boost.Python library. It would be significantly more efficient than native Python performance.

[EmperorYP7]

Good work.
You can create a Pull Request for this.

Sure. But I think I should research it a bit more before diving in.

[hsluoyz]

@EmperorYP7 does pybind11 require CMake? I think we are not using CMake in this repo now? I remembered we are using .sln for Windows MSVC and makefile for Linux, the repo doesn't even build for macOS yet. How to resolve this?

[EmperorYP7]

does pybind11 require CMake?

Not necessarily, but it's the best way to get it done. Details: https://pybind11.readthedocs.io/en/stable/compiling.html

I think we are not using CMake in this repo now?

The project currently supports building the casbin library through CMake.

the repo doesn't even build for macOS yet

It does through CMake. But not reliably.

@hsluoyz I am willing to work on an easy-to-maintain build system based on CMake. This would also include .sln and .proj files on building for Windows while also being compatible with Linux and macOS. Kindly see this file: https://github.com/EmperorYP7/casbin-cpp/blob/python-bindings/CMakeLists.txt

[hsluoyz]

lgtm!

[hsluoyz]

@EmperorYP7 can you share what parts are still missing to make PyCasbin-on-CPP work? Maybe @sheny1xuan and @noob20000405 can continue the work. Should we open this issue again or raise a new issue to track the progress?

[EmperorYP7]

can you share what parts are still missing to make PyCasbin-on-CPP work?

I completely missed this one!

• Making pycasbin module pip installable instead of building it locally from the source.
• Benchmarking pycasbin's performance to compare it with Python's casbin implementation

[hsluoyz]

@EmperorYP7 great! Created two issues:

#180

#181