如何遍历Python中的JSON对象并保存到CSV文件？

Question

I have Python script which retrieves data from an API in JSON format (at least I think its JSON format). I want to loop through each 'object' and write to a CSV file.

Here is the data returned from the api:

[
{
    "bids_won": "7",
    "partner_revenue": "$0.01",
    "profit": "$0.00",
    "campaign_id": "test 1", 
    "post_click_conversions": "0", 
    "total_cost": "$0.01",
    "total_media_cost": "$0.01",
    "post_view_conversions": "2", 
    "adjusted_partner_cost": "$0.01", 
    "clicks": "0",
    "day": "August 21, 2011"
},
{
    "bids_won": "30,209", 
    "partner_revenue": "$38.67", 
    "profit": "$8.92", 
    "campaign_id": "test 2", 
    "post_click_conversions": "0", 
    "total_cost": "$29.75", 
    "total_media_cost": "$29.75", 
    "post_view_conversions": "0", 
    "adjusted_partner_cost  ": "$25.26", 
    "clicks": "10", 
    "day": "August 21, 2011"
}
 ]

How can I loop through these 'objects' and write them to a CSV file? My current attempt to loop through it results in the script interating through each letter..

Appreciate the help.

ps I'm using python 2.7

Answer 1

To convert this to a proper csv file, with keys as a header row, something like this should do it, where "data" is the string containing your json:

import json
from csv import DictWriter
dicts = json.loads(data)
the_file = open("sample.csv", "w")
writer = DictWriter(the_file, dicts[0].keys())
writer.writeheader()
writer.writerows(dicts)
the_file.close()

Note that as of Python 2.6, simplejson has been included in the standard library as "json".

Answer 2

import json
import csv
temp = json.load(open('filename.json','r'))
output =[]
for each in temp:
     row = {}
     row['field1'] =each['field1']
     row['field2'] = each['field2']
     output.append(row)
file = open( "filename_destination.csv", "w")

fileWriter = csv.writer(file , delimiter=",",quotechar='"', quoting=csv.QUOTE_MINIMAL)

Header = ['field1','field2']

fileWriter.writerow(Header)

for x in output:
te = [x['field1'],x['field2']]
fileWriter.writerow(te)
file.close()

Answer 3

Try using simplejson to convert the JSON string to a native Python object. You should then be able to loop through the objects using a standard for loop.

http://pypi.python.org/pypi/simplejson/

data = simplejson.loads(JSON_STRING)

Answer 4

This will do it:

import json
for i in json.loads(json_string):
    print ','.join(i)

See json module docs

Answer 5

You should use simplejson : http://pypi.python.org/pypi/simplejson/

With simplejson you can simply do:

import simplejson as json

info = """[
{
    "bids_won": "7",
    "partner_revenue": "$0.01",
    "profit": "$0.00",
    "campaign_id": "test 1", 
    "post_click_conversions": "0", 
    "total_cost": "$0.01",
    "total_media_cost": "$0.01",
    "post_view_conversions": "2", 
    "adjusted_partner_cost": "$0.01", 
    "clicks": "0",
    "day": "August 21, 2011"
},
{
    "bids_won": "30,209", 
    "partner_revenue": "$38.67", 
    "profit": "$8.92", 
    "campaign_id": "test 2", 
    "post_click_conversions": "0", 
    "total_cost": "$29.75", 
    "total_media_cost": "$29.75", 
    "post_view_conversions": "0", 
    "adjusted_partner_cost  ": "$25.26", 
    "clicks": "10", 
    "day": "August 21, 2011"
}
 ]"""

data = json.loads(info)

And data will be a python list that you can iterate through.

Answer 6

In the end I was given a slightly different URL for the request which returned raw CSV. I dumped the content into a CSV file:

f = open('report.csv', 'wb')
f.write(response_content)
f.close

Its not an ideal solution because I still cannot loop through the CSV objects (goes through each character) but I'm able to create a resonably well formatted csv file so its ok for now.