Converting Multilevel JSON To 2D CSV With EsProc

Problem description & analysis
Below is data in JSON file json.json:
To convert the multilevel JSON file into a two-dimensional structure while splitting the two subfields under identities field and promoting them to the parent level, and store data as a CSV file as follows:

Solution:
We write the following script p1.dfx in esProc:

Code description:
A1   Read data of the JSON file as a string.
A2  Parse the string into a multilevel table sequence according to the original structure while splitting and promoting identities.signInType and identities.issuerAssignedId to their parent level with...