Convert a JSON datadump of a Django model into CSV format. Note: This only exports the fields dict, so you won't have pk in the output.

json2csv.py

# -*- coding: utf-8 -*-

import codecs
import cStringIO
import csv
import json
import sys

"""
Convert Django json datadump fields into csv.

Usage:
  json2csv.py <input_file.json> <output_file.csv>

Notes:
  UTF8 classes taken from [Python csv examples](http://docs.python.org/2/library/csv.html#examples).
"""


def main():
    file_json = sys.argv[1]
    file_csv = sys.argv[2]
    with open(file_json) as fi:
        data = json.load(fi)

    fields = data[0]['fields'].keys()

    with open(file_csv, 'wb') as fo:
        o = UnicodeWriter(fo)
        o.writerow(fields)
        for record in data:
            o.writerow(record['fields'].values())


class UTF8Recoder:
    """
    Iterator that reads an encoded stream and reencodes the input to UTF-8
    """
    def __init__(self, f, encoding):
        self.reader = codecs.getreader(encoding)(f)

    def __iter__(self):
        return self

    def next(self):
        return self.reader.next().encode("utf-8")


class UnicodeReader:
    """
    A CSV reader which will iterate over lines in the CSV file "f",
    which is encoded in the given encoding.
    """

    def __init__(self, f, dialect=csv.excel, encoding="utf-8", **kwds):
        f = UTF8Recoder(f, encoding)
        self.reader = csv.reader(f, dialect=dialect, **kwds)

    def next(self):
        row = self.reader.next()
        return [unicode(s, "utf-8") for s in row]

    def __iter__(self):
        return self


class UnicodeWriter:
    """
    A CSV writer which will write rows to CSV file "f",
    which is encoded in the given encoding.
    """

    def __init__(self, f, dialect=csv.excel, encoding="utf-8", **kwds):
        # Redirect output to a queue
        self.queue = cStringIO.StringIO()
        self.writer = csv.writer(self.queue, dialect=dialect, **kwds)
        self.stream = f
        self.encoder = codecs.getincrementalencoder(encoding)()

    def writerow(self, row):
        self.writer.writerow([unicode(s).encode("utf-8") for s in row])
        # Fetch UTF-8 output from the queue ...
        data = self.queue.getvalue()
        data = data.decode("utf-8")
        # ... and reencode it into the target encoding
        data = self.encoder.encode(data)
        # write to the target stream
        self.stream.write(data)
        # empty queue
        self.queue.truncate(0)

    def writerows(self, rows):
        for row in rows:
            self.writerow(row)

if __name__ == "__main__":
    main()