1 r"""

     2 A simple, fast, extensible JSON encoder and decoder

     3 

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

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

     6 interchange format.

     7 

     8 simplejson exposes an API familiar to uses of the standard library

     9 marshal and pickle modules.

    10 

    11 Encoding basic Python object hierarchies::

    12     

    13     >>> import simplejson

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

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

    16     >>> print simplejson.dumps("\"foo\bar")

    17     "\"foo\bar"

    18     >>> print simplejson.dumps(u'\u1234')

    19     "\u1234"

    20     >>> print simplejson.dumps('\\')

    21     "\\"

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

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

    24     >>> from StringIO import StringIO

    25     >>> io = StringIO()

    26     >>> simplejson.dump(['streaming API'], io)

    27     >>> io.getvalue()

    28     '["streaming API"]'

    29 

    30 Compact encoding::

    31 

    32     >>> import simplejson

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

    34     '[1,2,3,{"4":5,"6":7}]'

    35 

    36 Pretty printing::

    37 

    38     >>> import simplejson

    39     >>> print simplejson.dumps({'4': 5, '6': 7}, sort_keys=True, indent=4)

    40     {

    41         "4": 5, 

    42         "6": 7

    43     }

    44 

    45 Decoding JSON::

    46     

    47     >>> import simplejson

    48     >>> simplejson.loads('["foo", {"bar":["baz", null, 1.0, 2]}]')

    49     [u'foo', {u'bar': [u'baz', None, 1.0, 2]}]

    50     >>> simplejson.loads('"\\"foo\\bar"')

    51     u'"foo\x08ar'

    52     >>> from StringIO import StringIO

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

    54     >>> simplejson.load(io)

    55     [u'streaming API']

    56 

    57 Specializing JSON object decoding::

    58 

    59     >>> import simplejson

    60     >>> def as_complex(dct):

    61     ...     if '__complex__' in dct:

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

    63     ...     return dct

    64     ... 

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

    66     ...     object_hook=as_complex)

    67     (1+2j)

    68 

    69 Extending JSONEncoder::

    70     

    71     >>> import simplejson

    72     >>> class ComplexEncoder(simplejson.JSONEncoder):

    73     ...     def default(self, obj):

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

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

    76     ...         return simplejson.JSONEncoder.default(self, obj)

    77     ... 

    78     >>> dumps(2 + 1j, cls=ComplexEncoder)

    79     '[2.0, 1.0]'

    80     >>> ComplexEncoder().encode(2 + 1j)

    81     '[2.0, 1.0]'

    82     >>> list(ComplexEncoder().iterencode(2 + 1j))

    83     ['[', '2.0', ', ', '1.0', ']']

    84     

    85 

    86 Note that the JSON produced by this module's default settings

    87 is a subset of YAML, so it may be used as a serializer for that as well.

    88 """

    89 __version__ = '1.5'

    90 __all__ = [

    91     'dump', 'dumps', 'load', 'loads',

    92     'JSONDecoder', 'JSONEncoder',

    93 ]

    94 

    95 from django.utils.simplejson.decoder import JSONDecoder

    96 from django.utils.simplejson.encoder import JSONEncoder

    97 

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

    99         allow_nan=True, cls=None, indent=None, **kw):

   100     """

   101     Serialize ``obj`` as a JSON formatted stream to ``fp`` (a

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

   103 

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

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

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

   107 

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

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

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

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

   112     to cause an error.

   113 

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

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

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

   117 

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

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

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

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

   122 

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

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

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

   126 

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

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

   129     the ``cls`` kwarg.

   130     """

   131     if cls is None:

   132         cls = JSONEncoder

   133     iterable = cls(skipkeys=skipkeys, ensure_ascii=ensure_ascii,

   134         check_circular=check_circular, allow_nan=allow_nan, indent=indent,

   135         **kw).iterencode(obj)

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

   137     # a debuggability cost

   138     for chunk in iterable:

   139         fp.write(chunk)

   140 

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

   142         allow_nan=True, cls=None, indent=None, separators=None, **kw):

   143     """

   144     Serialize ``obj`` to a JSON formatted ``str``.

   145 

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

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

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

   149 

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

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

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

   153 

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

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

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

   157 

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

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

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

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

   162 

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

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

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

   166     representation.

   167 

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

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

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

   171 

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

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

   174     the ``cls`` kwarg.

   175     """

   176     if cls is None:

   177         cls = JSONEncoder

   178     return cls(

   179         skipkeys=skipkeys, ensure_ascii=ensure_ascii,

   180         check_circular=check_circular, allow_nan=allow_nan, indent=indent,

   181         separators=separators,

   182         **kw).encode(obj)

   183 

   184 def load(fp, encoding=None, cls=None, object_hook=None, **kw):

   185     """

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

   187     a JSON document) to a Python object.

   188 

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

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

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

   192     not allowed, and should be wrapped with

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

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

   195 

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

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

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

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

   200     

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

   202     kwarg.

   203     """

   204     if cls is None:

   205         cls = JSONDecoder

   206     if object_hook is not None:

   207         kw['object_hook'] = object_hook

   208     return cls(encoding=encoding, **kw).decode(fp.read())

   209 

   210 def loads(s, encoding=None, cls=None, object_hook=None, **kw):

   211     """

   212     Deserialize ``s`` (a ``str`` or ``unicode`` instance containing a JSON

   213     document) to a Python object.

   214 

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

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

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

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

   219 

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

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

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

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

   224 

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

   226     kwarg.

   227     """

   228     if cls is None:

   229         cls = JSONDecoder

   230     if object_hook is not None:

   231         kw['object_hook'] = object_hook

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

   233 

   234 def read(s):

   235     """

   236     json-py API compatibility hook.  Use loads(s) instead.

   237     """

   238     import warnings

   239     warnings.warn("simplejson.loads(s) should be used instead of read(s)",

   240         DeprecationWarning)

   241     return loads(s)

   242 

   243 def write(obj):

   244     """

   245     json-py API compatibility hook.  Use dumps(s) instead.

   246     """

   247     import warnings

   248     warnings.warn("simplejson.dumps(s) should be used instead of write(s)",

   249         DeprecationWarning)

   250     return dumps(obj)

   251 

   252