Flatten/denormalise nested json objects in jsonlines input file to a flat CSV.

flatten.py

import fileinput
import json
import sys
import csv
from copy import copy

fieldnames = [
    'regno',
    'name',
    'status',
    'member_id',
    'member_first_names',
    'member_last_name',
    'member_position',
    'member_status',
    'type',
    'regdate',
    'physaddress',
    'postaddress',
    'compliance',
]

writer = csv.DictWriter(sys.stdout, fieldnames=fieldnames)
#writer.writeheader()
for line in fileinput.input():
    company = json.loads(line)
    company['physaddress'] = company['physaddress'].replace("\n", ", ")
    company['postaddress'] = company['postaddress'].replace("\n", ", ")
    # fake an empty directory if none
    if not company['directors']:
        company['directors'] = [[None, None, None, None, None]]
    for director in company['directors']:
        row = copy(company)
        del row['directors']
        row['member_id'] = director[0]
        row['member_first_names'] = director[1]
        row['member_last_name'] = director[2]
        row['member_position'] = director[3]
        row['member_status'] = director[4]
        writer.writerow(row)