FBThrift 'py3' support needed: No module named 'openr.thrift' about openr

[cooperlees]

breeze (and OpenR components) all use fbthrift (fork of Apache thrift) to communicate. I believe these modules are missing as we’re not building the ‘py3’ thrift language client libraries and structures.

These are a little more involved as they are Cython libraries linked to the C++ libraries. I haven’t yet, but need to workout how to get these building in OSS world.

We could see if we can just add thrift compiler to use ‘py3’ as well, but I feel we’ll need cpp2 first for py3 to build.

[sgiannoulis]

I also see the same problem with making breeze operational. Thrift python libraries are not built, and trying to manually build them for the thrift repo is not working as the setup script requires specific built files to be in a specific folder within the trift repo (old way was all deps were in /build directory of openr and actually being installed, so the setup.py was working). When trying to run the thrift setup.py file, python cannot find module X ( where X was trift, then its dependency fb303, then neteng etc). Please provide an integrated solution for breeze to be operational through your install scripts.

[cooperlees]

I have attempted to do exactly this and the problem is much deeper. py3 thrift is Cython wrapped C++ and is off by default in the Open Source fbthrift builds. I've approached the team for support in making this work, but I have not been successful thus far unfortunately.

Some of my work can be seen in this branch: https://github.com/facebook/openr/tree/breeze_docker

I will try find cycles again some day soon, but without FB Thrift teams help, it's going to need to be very hacky. I want this for my home OpenR install, but may end up writing a lightweight non thrift py3 breeze for OSS to work around it.

[sgiannoulis]

I have managed in the past to get fbthrift to compile the python modules as well. (it was with the Release Candidate 20191208-10906 codebase). It needed to find the python-six package during configuration of cmake and then you were able to run the related setup.py to build and install also the related python wrappers.
If that helps, that was the cmake call that enabled python support build (running cmake inside the build dir of fbthrift root dir.
You needed to have python-six project built and:

cmake -Dpython-six_DIR=/opt/python-six/python-six-Q8Be2n47Opv-n5B-m-qxwvUlULZRCVNgM-AharcWT7Q/lib/cmake/python-six/ -DBUILD_SHARED_LIBS=ON ../

[cooperlees]

Ok, we have thrift py3 modules compiling in the Docker container - Just a few more install placements for the thrift files ans we should have breeze workable in Docker.

We can then use these learning to try make this more friendly and widely usable.