Auto-generate the API client code from OpenAPI details

[judgej]

There is an Open API description hidden behind the Starling Payments API documentation. It would be really great if that were officially published, then we could keep track of updates and build code from it automatically.

I have extracted that OpenAPI description here (some time ago): https://github.com/academe/starling-payments-api-sdk/tree/master/openapi

I have built API code from that description here: https://github.com/academe/starling-payments-api-sdk/tree/master/api/src That is all 100% generated code. That's what we want to see more of. That's what we should be using.

[judgej]

Note: the OpenAPI details are less hidden now, and available here:

https://payment-api-sandbox.starlingbank.com/api/openapi.json

[judgej]

v3.0.1 of the OpenAPI description:

starling-openapi-3.0.1.json.zip