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1r"""JSON (JavaScript Object Notation) <http://json.org> is a subset of2JavaScript syntax (ECMA-262 3rd edition) used as a lightweight data3interchange format.4 5:mod:`json` exposes an API familiar to users of the standard library6:mod:`marshal` and :mod:`pickle` modules.  It is derived from a7version of the externally maintained simplejson library.8 9Encoding basic Python object hierarchies::10 11    >>> import json12    >>> json.dumps(['foo', {'bar': ('baz', None, 1.0, 2)}])13    '["foo", {"bar": ["baz", null, 1.0, 2]}]'14    >>> print(json.dumps("\"foo\bar"))15    "\"foo\bar"16    >>> print(json.dumps('\u1234'))17    "\u1234"18    >>> print(json.dumps('\\'))19    "\\"20    >>> print(json.dumps({"c": 0, "b": 0, "a": 0}, sort_keys=True))21    {"a": 0, "b": 0, "c": 0}22    >>> from io import StringIO23    >>> io = StringIO()24    >>> json.dump(['streaming API'], io)25    >>> io.getvalue()26    '["streaming API"]'27 28Compact encoding::29 30    >>> import json31    >>> mydict = {'4': 5, '6': 7}32    >>> json.dumps([1,2,3,mydict], separators=(',', ':'))33    '[1,2,3,{"4":5,"6":7}]'34 35Pretty printing::36 37    >>> import json38    >>> print(json.dumps({'4': 5, '6': 7}, sort_keys=True, indent=4))39    {40        "4": 5,41        "6": 742    }43 44Decoding JSON::45 46    >>> import json47    >>> obj = ['foo', {'bar': ['baz', None, 1.0, 2]}]48    >>> json.loads('["foo", {"bar":["baz", null, 1.0, 2]}]') == obj49    True50    >>> json.loads('"\\"foo\\bar"') == '"foo\x08ar'51    True52    >>> from io import StringIO53    >>> io = StringIO('["streaming API"]')54    >>> json.load(io)[0] == 'streaming API'55    True56 57Specializing JSON object decoding::58 59    >>> import json60    >>> def as_complex(dct):61    ...     if '__complex__' in dct:62    ...         return complex(dct['real'], dct['imag'])63    ...     return dct64    ...65    >>> json.loads('{"__complex__": true, "real": 1, "imag": 2}',66    ...     object_hook=as_complex)67    (1+2j)68    >>> from decimal import Decimal69    >>> json.loads('1.1', parse_float=Decimal) == Decimal('1.1')70    True71 72Specializing JSON object encoding::73 74    >>> import json75    >>> def encode_complex(obj):76    ...     if isinstance(obj, complex):77    ...         return [obj.real, obj.imag]78    ...     raise TypeError(f'Object of type {obj.__class__.__name__} '79    ...                     f'is not JSON serializable')80    ...81    >>> json.dumps(2 + 1j, default=encode_complex)82    '[2.0, 1.0]'83    >>> json.JSONEncoder(default=encode_complex).encode(2 + 1j)84    '[2.0, 1.0]'85    >>> ''.join(json.JSONEncoder(default=encode_complex).iterencode(2 + 1j))86    '[2.0, 1.0]'87 88 89Using json.tool from the shell to validate and pretty-print::90 91    $ echo '{"json":"obj"}' | python -m json.tool92    {93        "json": "obj"94    }95    $ echo '{ 1.2:3.4}' | python -m json.tool96    Expecting property name enclosed in double quotes: line 1 column 3 (char 2)97"""98__version__ = '2.0.9'99__all__ = [100    'dump', 'dumps', 'load', 'loads',101    'JSONDecoder', 'JSONDecodeError', 'JSONEncoder',102]103 104__author__ = 'Bob Ippolito <bob@redivi.com>'105 106from .decoder import JSONDecoder, JSONDecodeError107from .encoder import JSONEncoder108import codecs109 110_default_encoder = JSONEncoder(111    skipkeys=False,112    ensure_ascii=True,113    check_circular=True,114    allow_nan=True,115    indent=None,116    separators=None,117    default=None,118)119 120def dump(obj, fp, *, skipkeys=False, ensure_ascii=True, check_circular=True,121        allow_nan=True, cls=None, indent=None, separators=None,122        default=None, sort_keys=False, **kw):123    """Serialize ``obj`` as a JSON formatted stream to ``fp`` (a124    ``.write()``-supporting file-like object).125 126    If ``skipkeys`` is true then ``dict`` keys that are not basic types127    (``str``, ``int``, ``float``, ``bool``, ``None``) will be skipped128    instead of raising a ``TypeError``.129 130    If ``ensure_ascii`` is false, then the strings written to ``fp`` can131    contain non-ASCII characters if they appear in strings contained in132    ``obj``. Otherwise, all such characters are escaped in JSON strings.133 134    If ``check_circular`` is false, then the circular reference check135    for container types will be skipped and a circular reference will136    result in an ``RecursionError`` (or worse).137 138    If ``allow_nan`` is false, then it will be a ``ValueError`` to139    serialize out of range ``float`` values (``nan``, ``inf``, ``-inf``)140    in strict compliance of the JSON specification, instead of using the141    JavaScript equivalents (``NaN``, ``Infinity``, ``-Infinity``).142 143    If ``indent`` is a non-negative integer, then JSON array elements and144    object members will be pretty-printed with that indent level. An indent145    level of 0 will only insert newlines. ``None`` is the most compact146    representation.147 148    If specified, ``separators`` should be an ``(item_separator, key_separator)``149    tuple.  The default is ``(', ', ': ')`` if *indent* is ``None`` and150    ``(',', ': ')`` otherwise.  To get the most compact JSON representation,151    you should specify ``(',', ':')`` to eliminate whitespace.152 153    ``default(obj)`` is a function that should return a serializable version154    of obj or raise TypeError. The default simply raises TypeError.155 156    If *sort_keys* is true (default: ``False``), then the output of157    dictionaries will be sorted by key.158 159    To use a custom ``JSONEncoder`` subclass (e.g. one that overrides the160    ``.default()`` method to serialize additional types), specify it with161    the ``cls`` kwarg; otherwise ``JSONEncoder`` is used.162 163    """164    # cached encoder165    if (not skipkeys and ensure_ascii and166        check_circular and allow_nan and167        cls is None and indent is None and separators is None and168        default is None and not sort_keys and not kw):169        iterable = _default_encoder.iterencode(obj)170    else:171        if cls is None:172            cls = JSONEncoder173        iterable = cls(skipkeys=skipkeys, ensure_ascii=ensure_ascii,174            check_circular=check_circular, allow_nan=allow_nan, indent=indent,175            separators=separators,176            default=default, sort_keys=sort_keys, **kw).iterencode(obj)177    # could accelerate with writelines in some versions of Python, at178    # a debuggability cost179    for chunk in iterable:180        fp.write(chunk)181 182 183def dumps(obj, *, skipkeys=False, ensure_ascii=True, check_circular=True,184        allow_nan=True, cls=None, indent=None, separators=None,185        default=None, sort_keys=False, **kw):186    """Serialize ``obj`` to a JSON formatted ``str``.187 188    If ``skipkeys`` is true then ``dict`` keys that are not basic types189    (``str``, ``int``, ``float``, ``bool``, ``None``) will be skipped190    instead of raising a ``TypeError``.191 192    If ``ensure_ascii`` is false, then the return value can contain non-ASCII193    characters if they appear in strings contained in ``obj``. Otherwise, all194    such characters are escaped in JSON strings.195 196    If ``check_circular`` is false, then the circular reference check197    for container types will be skipped and a circular reference will198    result in an ``RecursionError`` (or worse).199 200    If ``allow_nan`` is false, then it will be a ``ValueError`` to201    serialize out of range ``float`` values (``nan``, ``inf``, ``-inf``) in202    strict compliance of the JSON specification, instead of using the203    JavaScript equivalents (``NaN``, ``Infinity``, ``-Infinity``).204 205    If ``indent`` is a non-negative integer, then JSON array elements and206    object members will be pretty-printed with that indent level. An indent207    level of 0 will only insert newlines. ``None`` is the most compact208    representation.209 210    If specified, ``separators`` should be an ``(item_separator, key_separator)``211    tuple.  The default is ``(', ', ': ')`` if *indent* is ``None`` and212    ``(',', ': ')`` otherwise.  To get the most compact JSON representation,213    you should specify ``(',', ':')`` to eliminate whitespace.214 215    ``default(obj)`` is a function that should return a serializable version216    of obj or raise TypeError. The default simply raises TypeError.217 218    If *sort_keys* is true (default: ``False``), then the output of219    dictionaries will be sorted by key.220 221    To use a custom ``JSONEncoder`` subclass (e.g. one that overrides the222    ``.default()`` method to serialize additional types), specify it with223    the ``cls`` kwarg; otherwise ``JSONEncoder`` is used.224 225    """226    # cached encoder227    if (not skipkeys and ensure_ascii and228        check_circular and allow_nan and229        cls is None and indent is None and separators is None and230        default is None and not sort_keys and not kw):231        return _default_encoder.encode(obj)232    if cls is None:233        cls = JSONEncoder234    return cls(235        skipkeys=skipkeys, ensure_ascii=ensure_ascii,236        check_circular=check_circular, allow_nan=allow_nan, indent=indent,237        separators=separators, default=default, sort_keys=sort_keys,238        **kw).encode(obj)239 240 241_default_decoder = JSONDecoder(object_hook=None, object_pairs_hook=None)242 243 244def detect_encoding(b):245    bstartswith = b.startswith246    if bstartswith((codecs.BOM_UTF32_BE, codecs.BOM_UTF32_LE)):247        return 'utf-32'248    if bstartswith((codecs.BOM_UTF16_BE, codecs.BOM_UTF16_LE)):249        return 'utf-16'250    if bstartswith(codecs.BOM_UTF8):251        return 'utf-8-sig'252 253    if len(b) >= 4:254        if not b[0]:255            # 00 00 -- -- - utf-32-be256            # 00 XX -- -- - utf-16-be257            return 'utf-16-be' if b[1] else 'utf-32-be'258        if not b[1]:259            # XX 00 00 00 - utf-32-le260            # XX 00 00 XX - utf-16-le261            # XX 00 XX -- - utf-16-le262            return 'utf-16-le' if b[2] or b[3] else 'utf-32-le'263    elif len(b) == 2:264        if not b[0]:265            # 00 XX - utf-16-be266            return 'utf-16-be'267        if not b[1]:268            # XX 00 - utf-16-le269            return 'utf-16-le'270    # default271    return 'utf-8'272 273 274def load(fp, *, cls=None, object_hook=None, parse_float=None,275        parse_int=None, parse_constant=None, object_pairs_hook=None, **kw):276    """Deserialize ``fp`` (a ``.read()``-supporting file-like object containing277    a JSON document) to a Python object.278 279    ``object_hook`` is an optional function that will be called with the280    result of any object literal decode (a ``dict``). The return value of281    ``object_hook`` will be used instead of the ``dict``. This feature282    can be used to implement custom decoders (e.g. JSON-RPC class hinting).283 284    ``object_pairs_hook`` is an optional function that will be called with the285    result of any object literal decoded with an ordered list of pairs.  The286    return value of ``object_pairs_hook`` will be used instead of the ``dict``.287    This feature can be used to implement custom decoders.  If ``object_hook``288    is also defined, the ``object_pairs_hook`` takes priority.289 290    To use a custom ``JSONDecoder`` subclass, specify it with the ``cls``291    kwarg; otherwise ``JSONDecoder`` is used.292    """293    return loads(fp.read(),294        cls=cls, object_hook=object_hook,295        parse_float=parse_float, parse_int=parse_int,296        parse_constant=parse_constant, object_pairs_hook=object_pairs_hook, **kw)297 298 299def loads(s, *, cls=None, object_hook=None, parse_float=None,300        parse_int=None, parse_constant=None, object_pairs_hook=None, **kw):301    """Deserialize ``s`` (a ``str``, ``bytes`` or ``bytearray`` instance302    containing a JSON document) to a Python object.303 304    ``object_hook`` is an optional function that will be called with the305    result of any object literal decode (a ``dict``). The return value of306    ``object_hook`` will be used instead of the ``dict``. This feature307    can be used to implement custom decoders (e.g. JSON-RPC class hinting).308 309    ``object_pairs_hook`` is an optional function that will be called with the310    result of any object literal decoded with an ordered list of pairs.  The311    return value of ``object_pairs_hook`` will be used instead of the ``dict``.312    This feature can be used to implement custom decoders.  If ``object_hook``313    is also defined, the ``object_pairs_hook`` takes priority.314 315    ``parse_float``, if specified, will be called with the string316    of every JSON float to be decoded. By default this is equivalent to317    float(num_str). This can be used to use another datatype or parser318    for JSON floats (e.g. decimal.Decimal).319 320    ``parse_int``, if specified, will be called with the string321    of every JSON int to be decoded. By default this is equivalent to322    int(num_str). This can be used to use another datatype or parser323    for JSON integers (e.g. float).324 325    ``parse_constant``, if specified, will be called with one of the326    following strings: -Infinity, Infinity, NaN.327    This can be used to raise an exception if invalid JSON numbers328    are encountered.329 330    To use a custom ``JSONDecoder`` subclass, specify it with the ``cls``331    kwarg; otherwise ``JSONDecoder`` is used.332    """333    if isinstance(s, str):334        if s.startswith('\ufeff'):335            raise JSONDecodeError("Unexpected UTF-8 BOM (decode using utf-8-sig)",336                                  s, 0)337    else:338        if not isinstance(s, (bytes, bytearray)):339            raise TypeError(f'the JSON object must be str, bytes or bytearray, '340                            f'not {s.__class__.__name__}')341        s = s.decode(detect_encoding(s), 'surrogatepass')342 343    if (cls is None and object_hook is None and344            parse_int is None and parse_float is None and345            parse_constant is None and object_pairs_hook is None and not kw):346        return _default_decoder.decode(s)347    if cls is None:348        cls = JSONDecoder349    if object_hook is not None:350        kw['object_hook'] = object_hook351    if object_pairs_hook is not None:352        kw['object_pairs_hook'] = object_pairs_hook353    if parse_float is not None:354        kw['parse_float'] = parse_float355    if parse_int is not None:356        kw['parse_int'] = parse_int357    if parse_constant is not None:358        kw['parse_constant'] = parse_constant359    return cls(**kw).decode(s)360