flojay

flojay provides incremental serialization of Python data structures as JSON documents, and an event-based JSON parser to allow for incremental deserialization. It can be used to create and process JSON documents that are larger than working memory.

It is based on yajl version 2, a copy of which is included in this distribution.

example

import flojay
import sys

# Produce JSON from a generator, printing partial results
# as they become available

encoder = flojay.JSONEncoder()
json_generator = encoder.iterencode(xrange(100))
for hunk in json_generator:
    print hunk


# Read an array of JSON numbers from stdin input,
# summing the values as they are read


class ExampleCallbacks(object):
    def __init__(self):
        self.sum = 0

    def handle_start_array(self):
        pass

    def handle_end_array(self):
        pass

    def handle_number(self, value):
        self.sum += value

callbacks = ExampleCallbacks()

parser = flojay.JSONEventParser(callbacks)

while 1:
    row = sys.stdin.readline()
    if len(row) == 0:
        break
    parser.parse(row)
    print "The current total is: %d" % (callbacks.sum,)