quick & dirty reading/writing of files containing multiple JSON objects

multijson.py

"""A couple of very simple utilities for reading and writing files
that contain multiple JSON values. Could be useful in situations where
you're generating a bunch of data for later processing and then, later,
you want to read it in an element at a time.

The json module doesn't really support streaming reads, though, so this
is limited by that. If you need real streaming, you probably want to use
something like ijson:
    http://pypi.python.org/pypi/ijson/
"""
import json
import StringIO

_decoder = json.JSONDecoder()
_encoder = json.JSONEncoder()
_space = '\n'

def dump(fp, iterable):
    """Write a sequence of values to a file-like object."""
    for obj in iterable:
        for chunk in _encoder.iterencode(obj):
            fp.write(chunk)
        fp.write(_space)

def dumps(iterable):
    """Like `dump` but returns a string."""
    fp = StringIO.StringIO()
    dump(fp, iterable)
    return fp.getvalue()

def loads(s):
    """A generator reading a sequence of JSON values from a string."""
    while s:
        s = s.strip()
        obj, pos = _decoder.raw_decode(s)
        if not pos:
            raise ValueError('no JSON object found at %i' % pos)
        yield obj
        s = s[pos:]

def load(fp):
    """Like `loads` but reads from a file-like object."""
    return loads(fp.read())