Protocol Buffers

protoc

protoc is the protocol buffer compiler: it compiles .proto files.

Apt based systems;

sudo apt install -y protobuf-compiler

A Python wrapper(?) can apparently be installed with

sudo apt-get install python-protobuf

On Windows, protoc.exe can be downloaded somewhere from here.

Alternatively, protocol buffers might be built directlly from the sources:

python setup.py build
python setup.py test
python setup.py install

.proto files contain service and message definitions.

Google developers: protocol buffers