NiFi + Groovy: how to build "bread crumbs" (PG.Names path from root to processor)?

[#1]

Hello!

I'm newbe in NiFi and Groovy.

I found here – "Solved: Re: Get the processor-group name in NIFI flow - Cloudera Community - 213662" (2018) – very interestion solution! Thank @mburgess !!!  

I have related question.

I want to build with Groovy dictionary for every proceccor where key = Proccesor ID, value = "bread crumbs" (full path to processor from root canvas – the string like this "PG1_Name" / "PG2_(Child_of_PG1)_Name" / "PG3_(Child_of_PG2)_Name" .

The quesions are:

1. How to get list of Process Groups in the root and in Each PG?
2. How to get list of Processors in Each PG?
3. How to organize in Groovy cycles for scan PGs?
4. How to save / read data in/from Groovy dictionary /  NiFi cache?

Thanks in advance for any help and suggestions!