How to parse data in JSON format?

My project is currently receiving a JSON message in python which I need to get bits of information out of. For the purposes of this, let’s set it to some simple JSON in a string:

jsonStr = '{"one" : "1", "two" : "2", "three" : "3"}'

So far I’ve been generating JSON requests using a list and then json.dumps, but to do the opposite of this I think I need to use json.loads. However I haven’t had much luck with it. Could anyone provide me a snippet that would return "2" with the input of "two" in the above example?

Answers:

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Method 1

Very simple:

import json
data = json.loads('{"one" : "1", "two" : "2", "three" : "3"}')
print data['two']  # Or `print(data['two'])` in Python 3

Method 2

Sometimes your json is not a string. For example if you are getting a json from a url like this:

j = urllib2.urlopen('http://site.com/data.json')

you will need to use json.load, not json.loads:

j_obj = json.load(j)

(it is easy to forget: the ‘s’ is for ‘string’)

Method 3

For URL or file, use json.load(). For string with .json content, use json.loads().

#! /usr/bin/python

import json
# from pprint import pprint

json_file = 'my_cube.json'
cube = '1'

with open(json_file) as json_data:
    data = json.load(json_data)

# pprint(data)

print "Dimension: ", data['cubes'][cube]['dim']
print "Measures:  ", data['cubes'][cube]['meas']

Method 4

Following is simple example that may help you:

json_string = """
{
    "pk": 1, 
    "fa": "cc.ee", 
    "fb": {
        "fc": "", 
        "fd_id": "12345"
    }
}"""

import json
data = json.loads(json_string)
if data["fa"] == "cc.ee":
    data["fb"]["new_key"] = "cc.ee was present!"

print json.dumps(data)

The output for the above code will be:

{"pk": 1, "fb": {"new_key": "cc.ee was present!", "fd_id": "12345", 
 "fc": ""}, "fa": "cc.ee"}

Note that you can set the ident argument of dump to print it like so (for example,when using print json.dumps(data , indent=4)):

{
    "pk": 1, 
    "fb": {
        "new_key": "cc.ee was present!", 
        "fd_id": "12345", 
        "fc": ""
    }, 
    "fa": "cc.ee"
}

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0