Add BHoMObject class to python - #233

Issues addressed by this PR

Closes #220

This implementation will have updates in the future to iron out bugs, but for now this works well as a link between serialised c# BHoM objects and python ones.

Also included a decorator designed to be added to methods so that they can have auto-deserialised properties if calling from a BHoM adapter for instance (all that the BHoM adapter would then have to do is send a JSON document containing the BHoM Serialised json, and python would handle the rest)

The main purpose of this addition is to enable a tighter connection between BHoM adapters and Python methods/objects. Basically to add a replica of the BHoMObject class from c# into python, as well as a (fairly) simple JSON encoder/decoder that directly converts BHoM serialised JSON into python BHoMObjects (or IObject for serialised non-BHoMObjects). This implementation also comes with methods for converting to and from json and dictionaries for simplicity (rather than requiring direct usage of the json serialisers). The JSON decoder and encoder will automatically convert between PascalCase (C# side) and camel_case (python side) which should make it simpler to use it as a base class for objects that already attempt replication of existing BHoMObjects.

It is intended that the BHoMObject class (similar to c#) will act as a base class, so the json converter methods are designed to allow converting to the correct type after deserialisation.

Basic usage:

from python_toolkit.bhom.bhom_object import BHoMObject

class SomeClass(BHoMObject):
    def __init__(self, other_property: str, **kwargs):
        _t = "BH.oM.Python.SomeClass"
        super().__init__(self, _t, other_property, **kwargs)
        
sc = SomeClass("this is an other property")

print(sc)
>>> "SomeClass of type BH.oM.Python.SomeClass, name: '', version: 'Unknown', id: '8be4df61-93ca-11d2-aa0d-00e098032b8c'"

j = sc.to_json() # creates json of the class in the BHoM style with PascalCase property names.
sc2 = SomeClass.from_json(j) # automatically converts PascalCase to camel_case, and creates an object of the correct type

print(sc2.other_property)
>>> "this is an other property"

This can also be used to bring BHoM Objects from c# directly into python without needing to create a new class for them (for instance BHoM geometry can be pulled and manipulated as required with no need for a defined class)

I have added tests that check serialisation/deserialisation and round trips for IObject and BHoMObjects.

Test files

Run the python unit tests (run_tests.bat) after build.

Changelog

• Added BHoMObject base class to python_toolkit.bhom.bhom_object
  • Added BHoMJSONDecoder and BHoMJSONEncoder to convert between BHoM and python objects
  • Added a decorator that allows functions/methods to be called with a json document/string, which automatically fills in the required arguments.

Additional comments