JSON formatted string to pandas dataframe

OK, I have been beating my head against the wall with this one all afternoon. I know that there are many similar posts, but I keep getting errors and am probably making a stupid mistake.

I am using the apyori package found here to do some transaction basket analysis: https://pypi.python.org/pypi/apyori/1.1.1

It appears that the packages dump_as_json() method spits out dictionaries of RelationRecords for each possible basket.

I want to take these json formatted dictionaries into one pandas dataframe, but have had fits with different errors when attempting to use pd.read_json().

Here is my code:

import apyori, shutil, os
from apyori import apriori
from apyori import dump_as_json
import pandas as pd
import json

try:
    from StringIO import StringIO
except ImportError:
    from io import StringIO

transactions = [
    ['Jersey','Magnet'],
    ['T-Shirt','Cap'],
    ['Magnet','T-Shirt'],
    ['Jersey', 'Pin'],
    ['T-Shirt','Cap']
]
results = list(apriori(transactions))
results_df = pd.DataFrame()
for RelationRecord in results:
    dump_as_json(RelationRecord,output_file)
print output_file.getvalue()
json_file = json.dumps(output_file.getvalue())
print json_file


print data_df.head()

Any ideas how to get the json formatted dictionaries stored in output_file into a pandas dataframe?

Solution

I would suggest reading up on StackOverflow's guidelines on producing a Minimal, Complete, and Verifiable example. Also, statements like "I keep getting errors" are not very helpful. That said, I took a look at your code and the source code for this apyori package. Typos aside, it looks like the problem line is here :

for RelationRecord in results:
    dump_as_json(RelationRecord,output_file)

You're creating a one-object-per-line JSON file (I think this is sometimes referred to as LSON or Line-JSON.) As a whole document, it just isn't valid JSON. You could try to keep this as a list of homogeneous dictionaries or some other pd.DataFrame friendly structure.

output = []
for RelationRecord in results:
    o = StringIO()
    dump_as_json(RelationRecord, o)
    output.append(json.loads(o.getvalue()))
data_df = pd.DataFrame(output)