Working with JSON in Python 2.6?

Question

I'm really new to Python, but I've picked a problem that actually pertains to work and I think as I figure out how to do it I'll learn along the way.

I have a directory full of JSON-formatted files. I've gotten as far as importing everything in the directory into a list, and iterating through the list to do a simple print that verifies I got the data.

I'm trying to figure out how to actually work with a given JSON object in Python. In javascript, its as simple as

var x = {'asd':'bob'}
alert( x.asd ) //alerts 'bob'

Accessing the various properties on an object is simple dot notation. What's the equivalent for Python?

So this is my code that is doing the import. I'd like to know how to work with the individual objects stored in the list.

#! /usr/local/bin/python2.6

import os, json

#define path to reports
reportspath = "reports/"

# Gets all json files and imports them

dir = os.listdir(reportspath)

jsonfiles = []

for fname in dir:
    with open(reportspath + fname,'r') as f:
        jsonfiles.append( json.load(f) )

for i in jsonfiles:
    print i #prints the contents of each file stored in jsonfiles

Answer 1

What you get when you json.load a file containing the JSON form of a Javascript object such as {'abc': 'def'} is a Python dictionary (normally and affectionately called a dict) (which in this case happens to have the same textual representation as the Javascript object).

To access a specific item, you use indexing, mydict['abc'], while in Javascript you'd use attribute-access notation, myobj.abc. What you get with attribute-access notation in Python are methods that you can call on your dict, for example mydict.keys() would give ['abc'], a list with all the key values that are present in the dictionary (in this case, only one, and it's a string).

Dictionaries are extremely rich in functionality, with a wealth of methods that will make your head spin plus strong support for many Python language structures (for example, you can loop on a dict, for k in mydict:, and k will step through the dictionary's keys, iteratively and sequentially).