auiselect2 multiselect populated from Rest Api in Macrobrowser

[Rosy Salameh]

Hello,

In my custom plugin , I want to have a parameter in macrobrowser of type auiselect2 multiselect that should be populated from a Rest Api.

I checked the following:https://community.atlassian.com/t5/Confluence-questions/How-to-make-a-parameter-a-label-picker-in-the-Macro-Browser/qaq-p/377605. But, the example provided is a label picker that gets all labels. 
how to implement such this field in macrobrowser please?

thanks,

Rosy