matildapeak-protobuf 2018.1

Cross-product protocol buffers

A library of python bindings for protocol buffer definitions used by one or more products in the Matilda Peak product suite.

The protocol buffers are used across multiple components and languages. At the outset we anticipate supporting Python, and Java/Scala. The root of all packages is src/main as required by build tools like Gradle. From there the directory must be matildapeak followed by component directories or a common directory. An example protocol message file might be: -:

src/main/matildapeak/patterncomponent/DelayMessage.proto

Fixing the Python import

The Python protocol buffer bindings use relative imports and do not function properly (at least this is true of Python 3.6 and protobuf 3.1.0).

The issue appears to be well documented but a workaround is to adjust the system path to include the directory of the chronicler site package. In a clean virtual environment this is easily achieved with the following: -:

import os
import sys
sys.path.append(os.path.join(sys.path[-1], 'chronicler'))

Rather than use [-1] a safer approach might be to locate the site-packages directory in the system path and use that - it may not be the last entry on the path.