Provide a NULL/None type in the CRD

[jklaise]

In Python it is a valid convention to use None as a default value for a parameter, however for Python components if we want to document in the deployment manifest all parameters with a default value of None, currently we would have to pass is as a STRING parameter and do post-processing in the Python wrapper (e.g. explicitly checking if the STRING is "None" and if so setting the parameter to None), this would introduces another convention to document.

[jklaise]

Alternative solutions:

• Make value field optional in the CRD:

  seldon-core/proto/seldon_deployment.proto

  Line 141 in 3d8b379

  required string value = 2;

• Make use of the json null value

In any case there will also be a change in the corresponding wrapper code.

[ukclivecox]

Given this seems to be more of a documenting process and I can't see a neat solution to fix this will close. Open if I am mistaken.