Extending Python with C++ is typically a painful process. It doesn't have to be. Tools
such as runcython and protobuf make it easy to pass structured data from Python to C++
and gain massive performance improvements. Google's protobuf library encourages simple and
maintanable interfaces between Python and C++ via fast serialization and deserialization of binary
messages. The runcython command line utility considerably simplifies the build process for
Cython, a static compiler for Python/Cython that makes wrapping C++ libraries a breeze.
In this example we pass an ObjectList protobuf message to a C++ function that prints its contents
and returns the number of elements in the list. Each element in the ObjectList message is an Object
message with two fields: name and id.
First, you need to install the following packages:
- protobuf (https://developers.google.com/protocol-buffers/?hl=en)
- runcython (https://github.com/Russell91/runcython)
Compile protobuf definition file for use by C++ and Python:
$ protoc -I=./ --python_out=./ --cpp_out=./ objlist.proto
Run Cython file:
$ runcython++ use_objlist.pyx '' "objlist.cpp objlist.pb.cc -lprotobuf"