1 r"""JSON (JavaScript Object Notation) <http://json.org> is a subset of

     2 JavaScript syntax (ECMA-262 3rd edition) used as a lightweight data

     3 interchange format.

     4 

     5 :mod:`simplejson` exposes an API familiar to users of the standard library

     6 :mod:`marshal` and :mod:`pickle` modules. It is the externally maintained

     7 version of the :mod:`json` library contained in Python 2.6, but maintains

     8 compatibility with Python 2.4 and Python 2.5 and (currently) has

     9 significant performance advantages, even without using the optional C

    10 extension for speedups.

    11 

    12 Encoding basic Python object hierarchies::

    13 

    14     >>> import simplejson as json

    15     >>> json.dumps(['foo', {'bar': ('baz', None, 1.0, 2)}])

    16     '["foo", {"bar": ["baz", null, 1.0, 2]}]'

    17     >>> print json.dumps("\"foo\bar")

    18     "\"foo\bar"

    19     >>> print json.dumps(u'\u1234')

    20     "\u1234"

    21     >>> print json.dumps('\\')

    22     "\\"

    23     >>> print json.dumps({"c": 0, "b": 0, "a": 0}, sort_keys=True)

    24     {"a": 0, "b": 0, "c": 0}

    25     >>> from StringIO import StringIO

    26     >>> io = StringIO()

    27     >>> json.dump(['streaming API'], io)

    28     >>> io.getvalue()

    29     '["streaming API"]'

    30 

    31 Compact encoding::

    32 

    33     >>> import simplejson as json

    34     >>> json.dumps([1,2,3,{'4': 5, '6': 7}], separators=(',',':'))

    35     '[1,2,3,{"4":5,"6":7}]'

    36 

    37 Pretty printing::

    38 

    39     >>> import simplejson as json

    40     >>> s = json.dumps({'4': 5, '6': 7}, sort_keys=True, indent=4)

    41     >>> print '\n'.join([l.rstrip() for l in  s.splitlines()])

    42     {

    43         "4": 5,

    44         "6": 7

    45     }

    46 

    47 Decoding JSON::

    48 

    49     >>> import simplejson as json

    50     >>> obj = [u'foo', {u'bar': [u'baz', None, 1.0, 2]}]

    51     >>> json.loads('["foo", {"bar":["baz", null, 1.0, 2]}]') == obj

    52     True

    53     >>> json.loads('"\\"foo\\bar"') == u'"foo\x08ar'

    54     True

    55     >>> from StringIO import StringIO

    56     >>> io = StringIO('["streaming API"]')

    57     >>> json.load(io)[0] == 'streaming API'

    58     True

    59 

    60 Specializing JSON object decoding::

    61 

    62     >>> import simplejson as json

    63     >>> def as_complex(dct):

    64     ...     if '__complex__' in dct:

    65     ...         return complex(dct['real'], dct['imag'])

    66     ...     return dct

    67     ...

    68     >>> json.loads('{"__complex__": true, "real": 1, "imag": 2}',

    69     ...     object_hook=as_complex)

    70     (1+2j)

    71     >>> import decimal

    72     >>> json.loads('1.1', parse_float=decimal.Decimal) == decimal.Decimal('1.1')

    73     True

    74 

    75 Specializing JSON object encoding::

    76 

    77     >>> import simplejson as json

    78     >>> def encode_complex(obj):

    79     ...     if isinstance(obj, complex):

    80     ...         return [obj.real, obj.imag]

    81     ...     raise TypeError("%r is not JSON serializable" % (o,))

    82     ...

    83     >>> json.dumps(2 + 1j, default=encode_complex)

    84     '[2.0, 1.0]'

    85     >>> json.JSONEncoder(default=encode_complex).encode(2 + 1j)

    86     '[2.0, 1.0]'

    87     >>> ''.join(json.JSONEncoder(default=encode_complex).iterencode(2 + 1j))

    88     '[2.0, 1.0]'

    89 

    90 

    91 Using simplejson.tool from the shell to validate and pretty-print::

    92 

    93     $ echo '{"json":"obj"}' | python -msimplejson.tool

    94     {

    95         "json": "obj"

    96     }

    97     $ echo '{ 1.2:3.4}' | python -msimplejson.tool

    98     Expecting property name: line 1 column 2 (char 2)

    99 """

   100 __version__ = '2.0.7'

   101 __all__ = [

   102     'dump', 'dumps', 'load', 'loads',

   103     'JSONDecoder', 'JSONEncoder',

   104 ]

   105 

   106 from decoder import JSONDecoder

   107 from encoder import JSONEncoder

   108 

   109 _default_encoder = JSONEncoder(

   110     skipkeys=False,

   111     ensure_ascii=True,

   112     check_circular=True,

   113     allow_nan=True,

   114     indent=None,

   115     separators=None,

   116     encoding='utf-8',

   117     default=None,

   118 )

   119 

   120 def dump(obj, fp, skipkeys=False, ensure_ascii=True, check_circular=True,

   121         allow_nan=True, cls=None, indent=None, separators=None,

   122         encoding='utf-8', default=None, **kw):

   123     """Serialize ``obj`` as a JSON formatted stream to ``fp`` (a

   124     ``.write()``-supporting file-like object).

   125 

   126     If ``skipkeys`` is ``True`` then ``dict`` keys that are not basic types

   127     (``str``, ``unicode``, ``int``, ``long``, ``float``, ``bool``, ``None``)

   128     will be skipped instead of raising a ``TypeError``.

   129 

   130     If ``ensure_ascii`` is ``False``, then the some chunks written to ``fp``

   131     may be ``unicode`` instances, subject to normal Python ``str`` to

   132     ``unicode`` coercion rules. Unless ``fp.write()`` explicitly

   133     understands ``unicode`` (as in ``codecs.getwriter()``) this is likely

   134     to cause an error.

   135 

   136     If ``check_circular`` is ``False``, then the circular reference check

   137     for container types will be skipped and a circular reference will

   138     result in an ``OverflowError`` (or worse).

   139 

   140     If ``allow_nan`` is ``False``, then it will be a ``ValueError`` to

   141     serialize out of range ``float`` values (``nan``, ``inf``, ``-inf``)

   142     in strict compliance of the JSON specification, instead of using the

   143     JavaScript equivalents (``NaN``, ``Infinity``, ``-Infinity``).

   144 

   145     If ``indent`` is a non-negative integer, then JSON array elements and object

   146     members will be pretty-printed with that indent level. An indent level

   147     of 0 will only insert newlines. ``None`` is the most compact representation.

   148 

   149     If ``separators`` is an ``(item_separator, dict_separator)`` tuple

   150     then it will be used instead of the default ``(', ', ': ')`` separators.

   151     ``(',', ':')`` is the most compact JSON representation.

   152 

   153     ``encoding`` is the character encoding for str instances, default is UTF-8.

   154 

   155     ``default(obj)`` is a function that should return a serializable version

   156     of obj or raise TypeError. The default simply raises TypeError.

   157 

   158     To use a custom ``JSONEncoder`` subclass (e.g. one that overrides the

   159     ``.default()`` method to serialize additional types), specify it with

   160     the ``cls`` kwarg.

   161 

   162     """

   163     # cached encoder

   164     if (skipkeys is False and ensure_ascii is True and

   165         check_circular is True and allow_nan is True and

   166         cls is None and indent is None and separators is None and

   167         encoding == 'utf-8' and default is None and not kw):

   168         iterable = _default_encoder.iterencode(obj)

   169     else:

   170         if cls is None:

   171             cls = JSONEncoder

   172         iterable = cls(skipkeys=skipkeys, ensure_ascii=ensure_ascii,

   173             check_circular=check_circular, allow_nan=allow_nan, indent=indent,

   174             separators=separators, encoding=encoding,

   175             default=default, **kw).iterencode(obj)

   176     # could accelerate with writelines in some versions of Python, at

   177     # a debuggability cost

   178     for chunk in iterable:

   179         fp.write(chunk)

   180 

   181 

   182 def dumps(obj, skipkeys=False, ensure_ascii=True, check_circular=True,

   183         allow_nan=True, cls=None, indent=None, separators=None,

   184         encoding='utf-8', default=None, **kw):

   185     """Serialize ``obj`` to a JSON formatted ``str``.

   186 

   187     If ``skipkeys`` is ``True`` then ``dict`` keys that are not basic types

   188     (``str``, ``unicode``, ``int``, ``long``, ``float``, ``bool``, ``None``)

   189     will be skipped instead of raising a ``TypeError``.

   190 

   191     If ``ensure_ascii`` is ``False``, then the return value will be a

   192     ``unicode`` instance subject to normal Python ``str`` to ``unicode``

   193     coercion rules instead of being escaped to an ASCII ``str``.

   194 

   195     If ``check_circular`` is ``False``, then the circular reference check

   196     for container types will be skipped and a circular reference will

   197     result in an ``OverflowError`` (or worse).

   198 

   199     If ``allow_nan`` is ``False``, then it will be a ``ValueError`` to

   200     serialize out of range ``float`` values (``nan``, ``inf``, ``-inf``) in

   201     strict compliance of the JSON specification, instead of using the

   202     JavaScript equivalents (``NaN``, ``Infinity``, ``-Infinity``).

   203 

   204     If ``indent`` is a non-negative integer, then JSON array elements and

   205     object members will be pretty-printed with that indent level. An indent

   206     level of 0 will only insert newlines. ``None`` is the most compact

   207     representation.

   208 

   209     If ``separators`` is an ``(item_separator, dict_separator)`` tuple

   210     then it will be used instead of the default ``(', ', ': ')`` separators.

   211     ``(',', ':')`` is the most compact JSON representation.

   212 

   213     ``encoding`` is the character encoding for str instances, default is UTF-8.

   214 

   215     ``default(obj)`` is a function that should return a serializable version

   216     of obj or raise TypeError. The default simply raises TypeError.

   217 

   218     To use a custom ``JSONEncoder`` subclass (e.g. one that overrides the

   219     ``.default()`` method to serialize additional types), specify it with

   220     the ``cls`` kwarg.

   221 

   222     """

   223     # cached encoder

   224     if (skipkeys is False and ensure_ascii is True and

   225         check_circular is True and allow_nan is True and

   226         cls is None and indent is None and separators is None and

   227         encoding == 'utf-8' and default is None and not kw):

   228         return _default_encoder.encode(obj)

   229     if cls is None:

   230         cls = JSONEncoder

   231     return cls(

   232         skipkeys=skipkeys, ensure_ascii=ensure_ascii,

   233         check_circular=check_circular, allow_nan=allow_nan, indent=indent,

   234         separators=separators, encoding=encoding, default=default,

   235         **kw).encode(obj)

   236 

   237 

   238 _default_decoder = JSONDecoder(encoding=None, object_hook=None)

   239 

   240 

   241 def load(fp, encoding=None, cls=None, object_hook=None, parse_float=None,

   242         parse_int=None, parse_constant=None, **kw):

   243     """Deserialize ``fp`` (a ``.read()``-supporting file-like object containing

   244     a JSON document) to a Python object.

   245 

   246     If the contents of ``fp`` is encoded with an ASCII based encoding other

   247     than utf-8 (e.g. latin-1), then an appropriate ``encoding`` name must

   248     be specified. Encodings that are not ASCII based (such as UCS-2) are

   249     not allowed, and should be wrapped with

   250     ``codecs.getreader(fp)(encoding)``, or simply decoded to a ``unicode``

   251     object and passed to ``loads()``

   252 

   253     ``object_hook`` is an optional function that will be called with the

   254     result of any object literal decode (a ``dict``). The return value of

   255     ``object_hook`` will be used instead of the ``dict``. This feature

   256     can be used to implement custom decoders (e.g. JSON-RPC class hinting).

   257 

   258     To use a custom ``JSONDecoder`` subclass, specify it with the ``cls``

   259     kwarg.

   260 

   261     """

   262     return loads(fp.read(),

   263         encoding=encoding, cls=cls, object_hook=object_hook,

   264         parse_float=parse_float, parse_int=parse_int,

   265         parse_constant=parse_constant, **kw)

   266 

   267 

   268 def loads(s, encoding=None, cls=None, object_hook=None, parse_float=None,

   269         parse_int=None, parse_constant=None, **kw):

   270     """Deserialize ``s`` (a ``str`` or ``unicode`` instance containing a JSON

   271     document) to a Python object.

   272 

   273     If ``s`` is a ``str`` instance and is encoded with an ASCII based encoding

   274     other than utf-8 (e.g. latin-1) then an appropriate ``encoding`` name

   275     must be specified. Encodings that are not ASCII based (such as UCS-2)

   276     are not allowed and should be decoded to ``unicode`` first.

   277 

   278     ``object_hook`` is an optional function that will be called with the

   279     result of any object literal decode (a ``dict``). The return value of

   280     ``object_hook`` will be used instead of the ``dict``. This feature

   281     can be used to implement custom decoders (e.g. JSON-RPC class hinting).

   282 

   283     ``parse_float``, if specified, will be called with the string

   284     of every JSON float to be decoded. By default this is equivalent to

   285     float(num_str). This can be used to use another datatype or parser

   286     for JSON floats (e.g. decimal.Decimal).

   287 

   288     ``parse_int``, if specified, will be called with the string

   289     of every JSON int to be decoded. By default this is equivalent to

   290     int(num_str). This can be used to use another datatype or parser

   291     for JSON integers (e.g. float).

   292 

   293     ``parse_constant``, if specified, will be called with one of the

   294     following strings: -Infinity, Infinity, NaN, null, true, false.

   295     This can be used to raise an exception if invalid JSON numbers

   296     are encountered.

   297 

   298     To use a custom ``JSONDecoder`` subclass, specify it with the ``cls``

   299     kwarg.

   300 

   301     """

   302     if (cls is None and encoding is None and object_hook is None and

   303             parse_int is None and parse_float is None and

   304             parse_constant is None and not kw):

   305         return _default_decoder.decode(s)

   306     if cls is None:

   307         cls = JSONDecoder

   308     if object_hook is not None:

   309         kw['object_hook'] = object_hook

   310     if parse_float is not None:

   311         kw['parse_float'] = parse_float

   312     if parse_int is not None:

   313         kw['parse_int'] = parse_int

   314     if parse_constant is not None:

   315         kw['parse_constant'] = parse_constant

   316     return cls(encoding=encoding, **kw).decode(s)