rmr 4.0.0

Python wrapper for RIC RMR

rmr-python

Summary, Limitations

This is a CTYPES wrapper around the C rmr library. It requires you have rmr installed.

That is, it is not a native re-implementation of the rmr library. This seems to come with pros and cons. On the positive side, wrapping the library was much less work; we only need to wrap the function signatures. Keeping up with the rmr spec is thus also less work, as when new functions are added into the C lib, we only need to again wrap the function signatures.

The downside is this seems to be Linux only currently. This wrapper immediately SIGABRT’s on Mac, and no one yet seems to know why. The other downside is that there are currently some functionality that needs to be ‘exported’ from the C library for this to be fully operational. For example, CTYPES does not have access to C header files, and important constants are defined in the C header files.

Possibly evaluate whether we could natively reimplement the API with the nano nng python bindings: https://pypi.org/project/pynng/

Not Yet Implemented

At the time of this writing (Aug 13 2019) The following C functions are not yet implemented in this library (do we need them?):

1. `extern void rmr_free_msg`
2. `extern rmr_mbuf_t* rmr_mtosend_msg`
3. `extern rmr_mbuf_t* rmr_call` (this has some problems AFAIU from Scott)
4. `extern rmr_mbuf_t* rmr_rcv_specific`
5. `extern int rmr_get_rcvfd`

Unit Testing

You can unit test in docker or outside of docker. The preferred method (by far) is to use Docker, because it encapsulates rmr, as well as ensuring that ports that rmr opens do not conflict with the host machine

docker build -t rmrunittestt:latest -f Dockerfile-Unit-Test   .

A coverage report will be shown in stdout.

It is possible to run tox locally provided that rmr is intalled, and you are prepared to have the test open ports (4562) as rmr_init must succeed for the tests to proceed.

tox
open htmlcov/index.html

The added benefit of the local option is that the coverage report can be viewed in html, which I find easier to read than the term coverage reort the docker build will print.

Installation

Prequisites

If rmr is not compiled on your system, see the below instructions for downloading and compiling rmr. This library expects that the rmr .so files are compiled and available.

From PyPi

pip install rmr==X.Y.Z

From Source

git clone "https://gerrit.o-ran-sc.org/r/ric-plt/lib/rmr"
cd rmr/src/bindings/rmr-python/
pip install .

Examples

See the examples directory.

Compiling rmr (if not already done on your system)

(Note, you may or may not need sudo in your final command, depending on permissions to /usr/local. The pack externals option to CMake is needed only if the NNG libary is not already installed on the system, and you do not wish to manually install it.)

git clone https://gerrit.oran-osc.org/r/ric-plt/lib/rmr
cd rmr
mkdir .build; cd .build; cmake .. -DPACK_EXTERNALS=1; sudo make install