Convert python pickle file to json

pkl_to_json.py

#!/usr/local/bin/python3
'''
Convert a pkl file into json file
'''
import sys
import os
import _pickle as pickle
import json


def convert_dict_to_json(file_path):
    with open(file_path, 'rb') as fpkl, open('%s.json' % file_path, 'w') as fjson:
        data = pickle.load(fpkl)
        json.dump(data, fjson, ensure_ascii=False, sort_keys=True, indent=4)


def main():
    if sys.argv[1] and os.path.isfile(sys.argv[1]):
        file_path = sys.argv[1]
        print("Processing %s ..." % file_path)
        convert_dict_to_json(file_path)
    else:
        print("Usage: %s abs_file_path" % (__file__))


if __name__ == '__main__':
    main()

This will not work if the dict has tuples.

Or numpy arrays

Just wanted to say thanks for this. Helped a lot with ensuring my pickled data was as intended.

This will not work if the dict has tuples.

@jcopps, if the dict or set types have the tuples, it should add some customized code snippets about traversing every dict to check the tuple position.
Then convert them to list type before using JSON dumps.

For example, I assume that the following record is one of set in pickle file:

record = {(1,2,3,3), (1,2,3,4)}
type(record) # set

Trying to use json.dumps to convert them to JSON, and it will throw following error:

TypeError: {(1, 2, 3, 3), (1, 2, 3, 4)} is not JSON serializable

io = StringIO()
json_string = json.dump(record, io, ensure_ascii=False, sort_keys=True, indent=0)

To fix that, it will do following code snippets firstly:

record = list(record) # [(1, 2, 3, 3), (1, 2, 3, 4)]

record_index=0
while record_index < len(record):
    record[record_index] = list(record[record_index])
    record_index += 1

print(record) # [[1, 2, 3, 3], [1, 2, 3, 4]]

Then using json.dumps again:

io = StringIO()
json_string = json.dump(record, io, ensure_ascii=False, sort_keys=True, indent=0)

print(io.getvalue())

"""
[
    [
        1,
        2,
        3,
        3
    ],
    [
        1,
        2,
        3,
        4
    ]
]
"""

It will be successful now :).

This will not work if the dict has tuples.

@jcopps, if the dict or set types have the tuples, it should add some customized code snippets about traversing every dict to check the tuple position.
Then convert them to list type before using JSON dumps.

For example, I assume that the following record is one of set in pickle file:

record = {(1,2,3,3), (1,2,3,4)}
type(record) # set

Trying to use json.dumps to convert them to JSON, and it will throw following error:

TypeError: {(1, 2, 3, 3), (1, 2, 3, 4)} is not JSON serializable

io = StringIO()
json_string = json.dump(record, io, ensure_ascii=False, sort_keys=True, indent=0)

To fix that, it will do following code snippets firstly:

record = list(record) # [(1, 2, 3, 3), (1, 2, 3, 4)]

record_index=0
while record_index < len(record):
    record[record_index] = list(record[record_index])
    record_index += 1

print(record) # [[1, 2, 3, 3], [1, 2, 3, 4]]

Then using json.dumps again:

io = StringIO()
json_string = json.dump(record, io, ensure_ascii=False, sort_keys=True, indent=0)

print(io.getvalue())

"""
[
    [
        1,
        2,
        3,
        3
    ],
    [
        1,
        2,
        3,
        4
    ]
]
"""

It will be successful now :).

Yes. I agree on that. But the JSON is no more reversible back to the way dictionary was.