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r"""
A simple, fast, extensible JSON encoder and decoder
JSON (JavaScript Object Notation) <http://json.org> is a subset of
JavaScript syntax (ECMA-262 3rd edition) used as a lightweight data
interchange format.
simplejson exposes an API familiar to uses of the standard library
marshal and pickle modules.
Encoding basic Python object hierarchies::
>>> import simplejson
>>> simplejson.dumps(['foo', {'bar': ('baz', None, 1.0, 2)}])
'["foo", {"bar": ["baz", null, 1.0, 2]}]'
>>> print simplejson.dumps("\"foo\bar")
"\"foo\bar"
>>> print simplejson.dumps(u'\u1234')
"\u1234"
>>> print simplejson.dumps('\\')
"\\"
>>> print simplejson.dumps({"c": 0, "b": 0, "a": 0}, sort_keys=True)
{"a": 0, "b": 0, "c": 0}
>>> from StringIO import StringIO
>>> io = StringIO()
>>> simplejson.dump(['streaming API'], io)
>>> io.getvalue()
'["streaming API"]'
Decoding JSON::
>>> import simplejson
>>> simplejson.loads('["foo", {"bar":["baz", null, 1.0, 2]}]')
[u'foo', {u'bar': [u'baz', None, 1.0, 2]}]
>>> simplejson.loads('"\\"foo\\bar"')
u'"foo\x08ar'
>>> from StringIO import StringIO
>>> io = StringIO('["streaming API"]')
>>> simplejson.load(io)
[u'streaming API']
Specializing JSON object decoding::
>>> import simplejson
>>> def as_complex(dct):
... if '__complex__' in dct:
... return complex(dct['real'], dct['imag'])
... return dct
...
>>> simplejson.loads('{"__complex__": true, "real": 1, "imag": 2}',
... object_hook=as_complex)
(1+2j)
Extending JSONEncoder::
>>> import simplejson
>>> class ComplexEncoder(simplejson.JSONEncoder):
... def default(self, obj):
... if isinstance(obj, complex):
... return [obj.real, obj.imag]
... return simplejson.JSONEncoder.default(self, obj)
...
>>> dumps(2 + 1j, cls=ComplexEncoder)
'[2.0, 1.0]'
>>> ComplexEncoder().encode(2 + 1j)
'[2.0, 1.0]'
>>> list(ComplexEncoder().iterencode(2 + 1j))
['[', '2.0', ', ', '1.0', ']']
Note that the JSON produced by this module is a subset of YAML,
so it may be used as a serializer for that as well.
"""
__version__ = '1.3'
__all__ = [
'dump', 'dumps', 'load', 'loads',
'JSONDecoder', 'JSONEncoder',
]
from decoder import JSONDecoder
from encoder import JSONEncoder
def dump(obj, fp, skipkeys=False, ensure_ascii=True, check_circular=True,
allow_nan=True, cls=None, **kw):
"""
Serialize ``obj`` as a JSON formatted stream to ``fp`` (a
``.write()``-supporting file-like object).
If ``skipkeys`` is ``True`` then ``dict`` keys that are not basic types
(``str``, ``unicode``, ``int``, ``long``, ``float``, ``bool``, ``None``)
will be skipped instead of raising a ``TypeError``.
If ``ensure_ascii`` is ``False``, then the some chunks written to ``fp``
may be ``unicode`` instances, subject to normal Python ``str`` to
``unicode`` coercion rules. Unless ``fp.write()`` explicitly
understands ``unicode`` (as in ``codecs.getwriter()``) this is likely
to cause an error.
If ``check_circular`` is ``False``, then the circular reference check
for container types will be skipped and a circular reference will
result in an ``OverflowError`` (or worse).
If ``allow_nan`` is ``False``, then it will be a ``ValueError`` to
serialize out of range ``float`` values (``nan``, ``inf``, ``-inf``)
in strict compliance of the JSON specification, instead of using the
JavaScript equivalents (``NaN``, ``Infinity``, ``-Infinity``).
To use a custom ``JSONEncoder`` subclass (e.g. one that overrides the
``.default()`` method to serialize additional types), specify it with
the ``cls`` kwarg.
"""
if cls is None:
cls = JSONEncoder
iterable = cls(skipkeys=skipkeys, ensure_ascii=ensure_ascii,
check_circular=check_circular, allow_nan=allow_nan,
**kw).iterencode(obj)
# could accelerate with writelines in some versions of Python, at
# a debuggability cost
for chunk in iterable:
fp.write(chunk)
def dumps(obj, skipkeys=False, ensure_ascii=True, check_circular=True,
allow_nan=True, cls=None, **kw):
"""
Serialize ``obj`` to a JSON formatted ``str``.
If ``skipkeys`` is ``True`` then ``dict`` keys that are not basic types
(``str``, ``unicode``, ``int``, ``long``, ``float``, ``bool``, ``None``)
will be skipped instead of raising a ``TypeError``.
If ``ensure_ascii`` is ``False``, then the return value will be a
``unicode`` instance subject to normal Python ``str`` to ``unicode``
coercion rules instead of being escaped to an ASCII ``str``.
If ``check_circular`` is ``False``, then the circular reference check
for container types will be skipped and a circular reference will
result in an ``OverflowError`` (or worse).
If ``allow_nan`` is ``False``, then it will be a ``ValueError`` to
serialize out of range ``float`` values (``nan``, ``inf``, ``-inf``) in
strict compliance of the JSON specification, instead of using the
JavaScript equivalents (``NaN``, ``Infinity``, ``-Infinity``).
To use a custom ``JSONEncoder`` subclass (e.g. one that overrides the
``.default()`` method to serialize additional types), specify it with
the ``cls`` kwarg.
"""
if cls is None:
cls = JSONEncoder
return cls(skipkeys=skipkeys, ensure_ascii=ensure_ascii,
check_circular=check_circular, allow_nan=allow_nan, **kw).encode(obj)
def load(fp, encoding=None, cls=None, object_hook=None, **kw):
"""
Deserialize ``fp`` (a ``.read()``-supporting file-like object containing
a JSON document) to a Python object.
If the contents of ``fp`` is encoded with an ASCII based encoding other
than utf-8 (e.g. latin-1), then an appropriate ``encoding`` name must
be specified. Encodings that are not ASCII based (such as UCS-2) are
not allowed, and should be wrapped with
``codecs.getreader(fp)(encoding)``, or simply decoded to a ``unicode``
object and passed to ``loads()``
``object_hook`` is an optional function that will be called with the
result of any object literal decode (a ``dict``). The return value of
``object_hook`` will be used instead of the ``dict``. This feature
can be used to implement custom decoders (e.g. JSON-RPC class hinting).
To use a custom ``JSONDecoder`` subclass, specify it with the ``cls``
kwarg.
"""
if cls is None:
cls = JSONDecoder
if object_hook is not None:
kw['object_hook'] = object_hook
return cls(encoding=encoding, **kw).decode(fp.read())
def loads(s, encoding=None, cls=None, object_hook=None, **kw):
"""
Deserialize ``s`` (a ``str`` or ``unicode`` instance containing a JSON
document) to a Python object.
If ``s`` is a ``str`` instance and is encoded with an ASCII based encoding
other than utf-8 (e.g. latin-1) then an appropriate ``encoding`` name
must be specified. Encodings that are not ASCII based (such as UCS-2)
are not allowed and should be decoded to ``unicode`` first.
``object_hook`` is an optional function that will be called with the
result of any object literal decode (a ``dict``). The return value of
``object_hook`` will be used instead of the ``dict``. This feature
can be used to implement custom decoders (e.g. JSON-RPC class hinting).
To use a custom ``JSONDecoder`` subclass, specify it with the ``cls``
kwarg.
"""
if cls is None:
cls = JSONDecoder
if object_hook is not None:
kw['object_hook'] = object_hook
return cls(encoding=encoding, **kw).decode(s)
def read(s):
"""
json-py API compatibility hook. Use loads(s) instead.
"""
import warnings
warnings.warn("simplejson.loads(s) should be used instead of read(s)",
DeprecationWarning)
return loads(s)
def write(obj):
"""
json-py API compatibility hook. Use dumps(s) instead.
"""
import warnings
warnings.warn("simplejson.dumps(s) should be used instead of write(s)",
DeprecationWarning)
return dumps(obj)