Create supporting framework for parsing plugin input parameters

[rmcdouga]

Currently, the parsing of inputs to a plugin is always ad-hoc code. This leads to a lot of code duplication and is an impediment to easily creating plugins. It would be nice if there was a declarative approach that could be used instead.

I am thinking of a Builder pattern where one builds a list of input parameters that one expects. Each parameter would have a name, whether it repeats, whether it is optional and a class type. The result would be used by the framework code to decode the input parameters into a result object (the decoded InputParameters object).

Ideally the result object would ideally allow the user to access individual outputs in a strongly typed fashion, however in the worst case scenario, perhaps it could be a Map<String, Object> keyed in each input parameters name.

Another idea would be for the caller to pass in a Java record class that the parsing routine would examine using reflection and use it to get the Input parameters and populate the Record. Each field's name would be used to retrieve parameters. If the field was an Optional<> this would indicate that the parameter was optional. If the field was a Collection of some sort, that would indicate that the parameter could repeat.

A precursor to this is probably implementing issue #12 .