Source code for webapp2_extras.json

# -*- coding: utf-8 -*-
"""
    webapp2_extras.json
    ===================

    JSON helpers for webapp2.

    :copyright: 2011 by tipfy.org.
    :license: Apache Sotware License, see LICENSE for details.
"""
from __future__ import absolute_import

import base64
import urllib

try:
    # Preference for installed library with updated fixes.
    # Also available in Google App Engine SDK >= 1.4.2.
    import simplejson as json
except ImportError: # pragma: no cover
    try:
        # Standard library module in Python >= 2.6.
        import json
    except ImportError: # pragma: no cover
        raise RuntimeError(
            'A JSON parser is required, e.g., simplejson at '
            'http://pypi.python.org/pypi/simplejson/')

assert hasattr(json, 'loads') and hasattr(json, 'dumps'), \
    'Expected a JSON module with the functions loads() and dumps().'


[docs]def encode(value, *args, **kwargs): """Serializes a value to JSON. This comes from `Tornado`_. :param value: A value to be serialized. :param args: Extra arguments to be passed to `json.dumps()`. :param kwargs: Extra keyword arguments to be passed to `json.dumps()`. :returns: The serialized value. """ # By default encode using a compact format. kwargs.setdefault('separators', (',', ':')) # JSON permits but does not require forward slashes to be escaped. # This is useful when json data is emitted in a <script> tag # in HTML, as it prevents </script> tags from prematurely terminating # the javascript. Some json libraries do this escaping by default, # although python's standard library does not, so we do it here. # See: http://goo.gl/WsXwv return json.dumps(value, *args, **kwargs).replace("</", "<\\/")
[docs]def decode(value, *args, **kwargs): """Deserializes a value from JSON. This comes from `Tornado`_. :param value: A value to be deserialized. :param args: Extra arguments to be passed to `json.loads()`. :param kwargs: Extra keyword arguments to be passed to `json.loads()`. :returns: The deserialized value. """ if isinstance(value, str): value = value.decode('utf-8') assert isinstance(value, unicode) return json.loads(value, *args, **kwargs)
[docs]def b64encode(value, *args, **kwargs): """Serializes a value to JSON and encodes it using base64. Parameters and return value are the same from :func:`encode`. """ return base64.b64encode(encode(value, *args, **kwargs))
[docs]def b64decode(value, *args, **kwargs): """Decodes a value using base64 and deserializes it from JSON. Parameters and return value are the same from :func:`decode`. """ return decode(base64.b64decode(value), *args, **kwargs)
[docs]def quote(value, *args, **kwargs): """Serializes a value to JSON and encodes it using urllib.quote. Parameters and return value are the same from :func:`encode`. """ return urllib.quote(encode(value, *args, **kwargs))
[docs]def unquote(value, *args, **kwargs): """Decodes a value using urllib.unquote and deserializes it from JSON. Parameters and return value are the same from :func:`decode`. """ return decode(urllib.unquote(value), *args, **kwargs)