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1r"""JSON (JavaScript Object Notation) <http://json.org> is a subset of
2JavaScript syntax (ECMA-262 3rd edition) used as a lightweight data
3interchange format.
4
5:mod:`json` exposes an API familiar to users of the standard library
6:mod:`marshal` and :mod:`pickle` modules.  It is derived from a
7version of the externally maintained simplejson library.
8
9Encoding basic Python object hierarchies::
10
11    >>> import json
12    >>> 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 StringIO
23    >>> io = StringIO()
24    >>> json.dump(['streaming API'], io)
25    >>> io.getvalue()
26    '["streaming API"]'
27
28Compact encoding::
29
30    >>> import json
31    >>> 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 json
38    >>> print(json.dumps({'4': 5, '6': 7}, sort_keys=True, indent=4))
39    {
40        "4": 5,
41        "6": 7
42    }
43
44Decoding JSON::
45
46    >>> import json
47    >>> obj = ['foo', {'bar': ['baz', None, 1.0, 2]}]
48    >>> json.loads('["foo", {"bar":["baz", null, 1.0, 2]}]') == obj
49    True
50    >>> json.loads('"\\"foo\\bar"') == '"foo\x08ar'
51    True
52    >>> from io import StringIO
53    >>> io = StringIO('["streaming API"]')
54    >>> json.load(io)[0] == 'streaming API'
55    True
56
57Specializing JSON object decoding::
58
59    >>> import json
60    >>> def as_complex(dct):
61    ...     if '__complex__' in dct:
62    ...         return complex(dct['real'], dct['imag'])
63    ...     return dct
64    ...
65    >>> json.loads('{"__complex__": true, "real": 1, "imag": 2}',
66    ...     object_hook=as_complex)
67    (1+2j)
68    >>> from decimal import Decimal
69    >>> json.loads('1.1', parse_float=Decimal) == Decimal('1.1')
70    True
71
72Specializing JSON object encoding::
73
74    >>> import json
75    >>> 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.tool
92    {
93        "json": "obj"
94    }
95    $ echo '{ 1.2:3.4}' | python -m json.tool
96    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, JSONDecodeError
107from .encoder import JSONEncoder
108import codecs
109
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`` (a
124    ``.write()``-supporting file-like object).
125
126    If ``skipkeys`` is true then ``dict`` keys that are not basic types
127    (``str``, ``int``, ``float``, ``bool``, ``None``) will be skipped
128    instead of raising a ``TypeError``.
129
130    If ``ensure_ascii`` is false, then the strings written to ``fp`` can
131    contain non-ASCII characters if they appear in strings contained in
132    ``obj``. Otherwise, all such characters are escaped in JSON strings.
133
134    If ``check_circular`` is false, then the circular reference check
135    for container types will be skipped and a circular reference will
136    result in an ``OverflowError`` (or worse).
137
138    If ``allow_nan`` is false, then it will be a ``ValueError`` to
139    serialize out of range ``float`` values (``nan``, ``inf``, ``-inf``)
140    in strict compliance of the JSON specification, instead of using the
141    JavaScript equivalents (``NaN``, ``Infinity``, ``-Infinity``).
142
143    If ``indent`` is a non-negative integer, then JSON array elements and
144    object members will be pretty-printed with that indent level. An indent
145    level of 0 will only insert newlines. ``None`` is the most compact
146    representation.
147
148    If specified, ``separators`` should be an ``(item_separator, key_separator)``
149    tuple.  The default is ``(', ', ': ')`` if *indent* is ``None`` and
150    ``(',', ': ')`` 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 version
154    of obj or raise TypeError. The default simply raises TypeError.
155
156    If *sort_keys* is true (default: ``False``), then the output of
157    dictionaries will be sorted by key.
158
159    To use a custom ``JSONEncoder`` subclass (e.g. one that overrides the
160    ``.default()`` method to serialize additional types), specify it with
161    the ``cls`` kwarg; otherwise ``JSONEncoder`` is used.
162
163    """
164    # cached encoder
165    if (not skipkeys and ensure_ascii and
166        check_circular and allow_nan and
167        cls is None and indent is None and separators is None and
168        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 = JSONEncoder
173        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, at
178    # a debuggability cost
179    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 types
189    (``str``, ``int``, ``float``, ``bool``, ``None``) will be skipped
190    instead of raising a ``TypeError``.
191
192    If ``ensure_ascii`` is false, then the return value can contain non-ASCII
193    characters if they appear in strings contained in ``obj``. Otherwise, all
194    such characters are escaped in JSON strings.
195
196    If ``check_circular`` is false, then the circular reference check
197    for container types will be skipped and a circular reference will
198    result in an ``OverflowError`` (or worse).
199
200    If ``allow_nan`` is false, then it will be a ``ValueError`` to
201    serialize out of range ``float`` values (``nan``, ``inf``, ``-inf``) in
202    strict compliance of the JSON specification, instead of using the
203    JavaScript equivalents (``NaN``, ``Infinity``, ``-Infinity``).
204
205    If ``indent`` is a non-negative integer, then JSON array elements and
206    object members will be pretty-printed with that indent level. An indent
207    level of 0 will only insert newlines. ``None`` is the most compact
208    representation.
209
210    If specified, ``separators`` should be an ``(item_separator, key_separator)``
211    tuple.  The default is ``(', ', ': ')`` if *indent* is ``None`` and
212    ``(',', ': ')`` 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 version
216    of obj or raise TypeError. The default simply raises TypeError.
217
218    If *sort_keys* is true (default: ``False``), then the output of
219    dictionaries will be sorted by key.
220
221    To use a custom ``JSONEncoder`` subclass (e.g. one that overrides the
222    ``.default()`` method to serialize additional types), specify it with
223    the ``cls`` kwarg; otherwise ``JSONEncoder`` is used.
224
225    """
226    # cached encoder
227    if (not skipkeys and ensure_ascii and
228        check_circular and allow_nan and
229        cls is None and indent is None and separators is None and
230        default is None and not sort_keys and not kw):
231        return _default_encoder.encode(obj)
232    if cls is None:
233        cls = JSONEncoder
234    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.startswith
246    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-be
256            # 00 XX -- -- - utf-16-be
257            return 'utf-16-be' if b[1] else 'utf-32-be'
258        if not b[1]:
259            # XX 00 00 00 - utf-32-le
260            # XX 00 00 XX - utf-16-le
261            # XX 00 XX -- - utf-16-le
262            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-be
266            return 'utf-16-be'
267        if not b[1]:
268            # XX 00 - utf-16-le
269            return 'utf-16-le'
270    # default
271    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 containing
277    a JSON document) to a Python object.
278
279    ``object_hook`` is an optional function that will be called with the
280    result of any object literal decode (a ``dict``). The return value of
281    ``object_hook`` will be used instead of the ``dict``. This feature
282    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 the
285    result of any object literal decoded with an ordered list of pairs.  The
286    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`` instance
302    containing a JSON document) to a Python object.
303
304    ``object_hook`` is an optional function that will be called with the
305    result of any object literal decode (a ``dict``). The return value of
306    ``object_hook`` will be used instead of the ``dict``. This feature
307    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 the
310    result of any object literal decoded with an ordered list of pairs.  The
311    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 string
316    of every JSON float to be decoded. By default this is equivalent to
317    float(num_str). This can be used to use another datatype or parser
318    for JSON floats (e.g. decimal.Decimal).
319
320    ``parse_int``, if specified, will be called with the string
321    of every JSON int to be decoded. By default this is equivalent to
322    int(num_str). This can be used to use another datatype or parser
323    for JSON integers (e.g. float).
324
325    ``parse_constant``, if specified, will be called with one of the
326    following strings: -Infinity, Infinity, NaN.
327    This can be used to raise an exception if invalid JSON numbers
328    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 and
344            parse_int is None and parse_float is None and
345            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 = JSONDecoder
349    if object_hook is not None:
350        kw['object_hook'] = object_hook
351    if object_pairs_hook is not None:
352        kw['object_pairs_hook'] = object_pairs_hook
353    if parse_float is not None:
354        kw['parse_float'] = parse_float
355    if parse_int is not None:
356        kw['parse_int'] = parse_int
357    if parse_constant is not None:
358        kw['parse_constant'] = parse_constant
359    return cls(**kw).decode(s)
360