[OE-core] Discussion about architecure of ptest-runner patch

[Markus Boos]

Hi

We patched the ptest-runner script to deliver a xUnit file as a rough overview/indicator over the package tests. 
Having such a report allows us to use the file in Jenkins and in our ALM tool to display the results of the ptest run.

Before we send the patch upstream I like to start the discussion about the architecture of the patch because I think it's worth to extend the ptest-runner to deliver the results in readable text format (xUnit, JSON, html table, csv,  whateverformat).
I think of something similar like the automated deployment mechanism where yocto delivers the base class and you can write your own extension with this class.

What is the best way to add such a feature?

Simply extend the ptest-runner script with the preferred output formatter?

Or

Write a bitbake class with an interface where you can attach your own preferred output formatter? 

I'm sure there are other solutions possible as well. If you have one in mind, please share it.

Thank you.

Best regards
Markus