OpenAPI spec for external and internal prediction APIs

[ukclivecox]

The APIs are presently described as gRPC/proto files.

Translating automatically to OpenAPI does not seem possible, see issue on OpenAPI project
There is an OpenAPI to proto Converter project so one possibility is to see how close a created manual OpenAPI spec of the current gRPC spec when sent through this recreates the existing gRPC spec. If this was identical we could think of just keeping the OpenAPI spec and generating the proto file.

[elgalu]

Are you guys planning to be SwaggerAPI compliant?

[ukclivecox]

Yes, we definitely want to. The question is how to convert the gRPC proto buffer message definitions which are presently the source of truth.

[ukclivecox]

fixed by #271