json2csv

#!/usr/bin/python
import sys,csv,json
import unicodecsv as csv

def flattenjson( b, delim ):
	val = {}
	for i in b:
		if isinstance( b[i], dict ) :
			get = flattenjson( b[i], delim )
			#print get
			try:
				int(i)
				if isinstance(val, dict):
					val=[]
				get['_id']=i
				val.append(get)
			except:
				if isinstance(get, list):
					val[i] = get
				else:
					for j in get:
						name = j
						val[ i + delim + name ] = get[j] 
		else:
			val[i] = b[i]

	return val

input = json.load(sys.stdin)
if type(input) is dict:
	input = [input]
input = map( lambda x: flattenjson( x, "." ), input )


columns = [ x for row in input for x in row.keys() ]
columns = list( set( columns ) )

csv_w = csv.writer( sys.stdout)
csv_w.writerow( columns )

for i_r in input:
	csv_w.writerow( map( lambda x: i_r.get( x, "" ), columns ) )