Does anyone know when the getSchema function is called, or what calls it?
For that matter does anyone know of any documentation that outlines the flow between the Google Data Studio Connector functions.
So I think I can answer my own question, but if anyone can add any clarification that would still be welcome.
It appears that this function provides the full list of connector fields, specifically when the connector is connected to a data source.
It may be called at other points as well which where some further clarification would be useful.