CSV to JSON script

Question

I took this script from here:

import csv
from itertools import izip
f = open( '/django/sw2/wkw2/csvtest1.csv', 'r' )
reader = csv.reader( f )
keys = ( "firm_url", "firm_name", "first", "last", "school", "year_graduated" )
out = []
for property in reader:
    property = iter( property )
    data = {}
    for key in keys:
        data[ key ] = property.next()
    out += [ data ]
print out

When I tried it in IDLE I got the error

Traceback (most recent call last):
  File "<pyshell#13>", line 5, in <module>
    data [key] = property.next()
StopIteration

But I tried

print out

again and then it printed

[{'school': 'The George Washington University Law School', 'last': 'Abbas', 'firm_url': 'http://www.whitecase.com/aabbas', 'year_graduated': ' 2005', 'firm_name': 'White & Case', 'first': ' Amr A '}, {'school': 'Ernst Moritz Arndt University Greifswald', 'last': 'Adam', 'firm_url': 'http://www.whitecase.com/kadam', 'year_graduated': ' 2004', 'firm_name': 'White & Case', 'first': ' Karin '}, {'school': 'Tashkent State Law Institute', 'last': 'Adjivefayev', 'firm_url': 'http://www.whitecase.com/vadjivefayev', 'year_graduated': ' 2002', 'firm_name': 'White & Case', 'first': ' Vilen '}]

But when I try to run it as a script, it doesn't work, I get the same error message.

Can anyone help fix the error?

(And is it outputting valid json?)

Thanks

Edit

Thanks for the answers. It seems that this is not the right way of converting a csv file to json format. I am just trying to convert the csv file with data in it so that I can use loaddata to populate my sqlite3 database in django. See this thread in django group: http://groups.google.com/group/django-users/browse_frm/thread/a00b529ba2147d91 for my attempt to use csv2json.py snippet. And another thread today in OS (Sorry I cannot include 2 links). I would appreciate a simple way of converting csv to json. Or the method you use to populate your django database that I should be using instead. Thanks for the help.

Answer 1

Change the nested for loop to:

out = [dict(zip(keys, property)) for property in reader]

and, no, print out will not emit valid JSON -- use print json.dumps(out) (you'll need to import json too of course -- that's a Python 2.6 standard library module but you can find versions working with 2.5 if that's what you need).

Answer 2

With the CSV Module you already have a dict reader built in! Here's an example script which can be used as a command line tool:

import csv
import json

def csvToJson( inFile, outFile ):
    out = None;

    with open( inFile, 'r') as csvFile:
        #Note this reads the first line as the keys we can add specific keys with:
        #csv.DictReader( csvFile, fieldnames=<LIST HERE>, restkey=None, restval=None, )
        csvDict = csv.DictReader( csvFile, restkey=None, restval=None, )
        out = [obj for obj in csvDict]

    if out:
        with open( outFile, 'w' ) as jsonFile:
            jsonFile.write( json.dumps( out ) );
    else:
       print "Error creating csv dict!"

if __name__ == "__main__":
     import argparse

     parser = argparse.ArgumentParser()
     parser.add_argument('inFile', nargs=1, help="Choose the in file to use")
     parser.add_argument('outFile', nargs=1, help="Choose the out file to use")
     args = parser.parse_args()
     csvToJson( args.inFile[0] , args.outFile[0] );