r"""JSON (JavaScript Object Notation) <http://json.org> is a subset of JavaScript syntax (ECMA-262 3rd edition) used as a lightweight data interchange format. :mod:`json` exposes an API familiar to users of the standard library :mod:`marshal` and :mod:`pickle` modules. It is derived from a version of the externally maintained simplejson library. Encoding basic Python object hierarchies:: >>> import json >>> json.dumps(['foo', {'bar': ('baz', None, 1.0, 2)}]) '["foo", {"bar": ["baz", null, 1.0, 2]}]' >>> print(json.dumps("\"foo\bar")) "\"foo\bar" >>> print(json.dumps('\u1234')) "\u1234" >>> print(json.dumps('\\')) "\\" >>> print(json.dumps({"c": 0, "b": 0, "a": 0}, sort_keys=True)) {"a": 0, "b": 0, "c": 0} >>> from io import StringIO >>> io = StringIO() >>> json.dump(['streaming API'], io) >>> io.getvalue() '["streaming API"]' Compact encoding:: >>> import json >>> mydict = {'4': 5, '6': 7} >>> json.dumps([1,2,3,mydict], separators=(',', ':')) '[1,2,3,{"4":5,"6":7}]' Pretty printing:: >>> import json >>> print(json.dumps({'4': 5, '6': 7}, sort_keys=True, indent=4)) { "4": 5, "6": 7 } Decoding JSON:: >>> import json >>> obj = ['foo', {'bar': ['baz', None, 1.0, 2]}] >>> json.loads('["foo", {"bar":["baz", null, 1.0, 2]}]') == obj True >>> json.loads('"\\"foo\\bar"') == '"foo\x08ar' True >>> from io import StringIO >>> io = StringIO('["streaming API"]') >>> json.load(io)[0] == 'streaming API' True Specializing JSON object decoding:: >>> import json >>> def as_complex(dct): ... if '__complex__' in dct: ... return complex(dct['real'], dct['imag']) ... return dct ... >>> json.loads('{"__complex__": true, "real": 1, "imag": 2}', ... object_hook=as_complex) (1+2j) >>> from decimal import Decimal >>> json.loads('1.1', parse_float=Decimal) == Decimal('1.1') True Specializing JSON object encoding:: >>> import json >>> def encode_complex(obj): ... if isinstance(obj, complex): ... return [obj.real, obj.imag] ... raise TypeError(f'Object of type {obj.__class__.__name__} ' ... f'is not JSON serializable') ... >>> json.dumps(2 + 1j, default=encode_complex) '[2.0, 1.0]' >>> json.JSONEncoder(default=encode_complex).encode(2 + 1j) '[2.0, 1.0]' >>> ''.join(json.JSONEncoder(default=encode_complex).iterencode(2 + 1j)) '[2.0, 1.0]' Using json.tool from the shell to validate and pretty-print:: $ echo '{"json":"obj"}' | python -m json.tool { "json": "obj" } $ echo '{ 1.2:3.4}' | python -m json.tool Expecting property name enclosed in double quotes: line 1 column 3 (char 2) """ __version__ = '2.0.9' __all__ = [ 'dump', 'dumps', 'load', 'loads', 'JSONDecoder', 'JSONDecodeError', 'JSONEncoder', ] __author__ = 'Bob Ippolito <bob@redivi.com>' from .decoder import JSONDecoder, JSONDecodeError from .encoder import JSONEncoder import codecs _default_encoder = JSONEncoder( skipkeys=False, ensure_ascii=True, check_circular=True, allow_nan=True, indent=None, separators=None, default=None, ) def dump(obj, fp, *, skipkeys=False, ensure_ascii=True, check_circular=True, allow_nan=True, cls=None, indent=None, separators=None, default=None, sort_keys=False, **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``, ``int``, ``float``, ``bool``, ``None``) will be skipped instead of raising a ``TypeError``. If ``ensure_ascii`` is false, then the strings written to ``fp`` can contain non-ASCII characters if they appear in strings contained in ``obj``. Otherwise, all such characters are escaped in JSON strings. 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``). If ``indent`` is a non-negative integer, then JSON array elements and object members will be pretty-printed with that indent level. An indent level of 0 will only insert newlines. ``None`` is the most compact representation. If specified, ``separators`` should be an ``(item_separator, key_separator)`` tuple. The default is ``(', ', ': ')`` if *indent* is ``None`` and ``(',', ': ')`` otherwise. To get the most compact JSON representation, you should specify ``(',', ':')`` to eliminate whitespace. ``default(obj)`` is a function that should return a serializable version of obj or raise TypeError. The default simply raises TypeError. If *sort_keys* is true (default: ``False``), then the output of dictionaries will be sorted by key. To use a custom ``JSONEncoder`` subclass (e.g. one that overrides the ``.default()`` method to serialize additional types), specify it with the ``cls`` kwarg; otherwise ``JSONEncoder`` is used. """ # cached encoder if (not skipkeys and ensure_ascii and check_circular and allow_nan and cls is None and indent is None and separators is None and default is None and not sort_keys and not kw): iterable = _default_encoder.iterencode(obj) else: if cls is None: cls = JSONEncoder iterable = cls(skipkeys=skipkeys, ensure_ascii=ensure_ascii, check_circular=check_circular, allow_nan=allow_nan, indent=indent, separators=separators, default=default, sort_keys=sort_keys, **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, indent=None, separators=None, default=None, sort_keys=False, **kw): """Serialize ``obj`` to a JSON formatted ``str``. If ``skipkeys`` is true then ``dict`` keys that are not basic types (``str``, ``int``, ``float``, ``bool``, ``None``) will be skipped instead of raising a ``TypeError``. If ``ensure_ascii`` is false, then the return value can contain non-ASCII characters if they appear in strings contained in ``obj``. Otherwise, all such characters are escaped in JSON strings. 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``). If ``indent`` is a non-negative integer, then JSON array elements and object members will be pretty-printed with that indent level. An indent level of 0 will only insert newlines. ``None`` is the most compact representation. If specified, ``separators`` should be an ``(item_separator, key_separator)`` tuple. The default is ``(', ', ': ')`` if *indent* is ``None`` and ``(',', ': ')`` otherwise. To get the most compact JSON representation, you should specify ``(',', ':')`` to eliminate whitespace. ``default(obj)`` is a function that should return a serializable version of obj or raise TypeError. The default simply raises TypeError. If *sort_keys* is true (default: ``False``), then the output of dictionaries will be sorted by key. To use a custom ``JSONEncoder`` subclass (e.g. one that overrides the ``.default()`` method to serialize additional types), specify it with the ``cls`` kwarg; otherwise ``JSONEncoder`` is used. """ # cached encoder if (not skipkeys and ensure_ascii and check_circular and allow_nan and cls is None and indent is None and separators is None and default is None and not sort_keys and not kw): return _default_encoder.encode(obj) if cls is None: cls = JSONEncoder return cls( skipkeys=skipkeys, ensure_ascii=ensure_ascii, check_circular=check_circular, allow_nan=allow_nan, indent=indent, separators=separators, default=default, sort_keys=sort_keys, **kw).encode(obj) _default_decoder = JSONDecoder(object_hook=None, object_pairs_hook=None) def detect_encoding(b): bstartswith = b.startswith if bstartswith((codecs.BOM_UTF32_BE, codecs.BOM_UTF32_LE)): return 'utf-32' if bstartswith((codecs.BOM_UTF16_BE, codecs.BOM_UTF16_LE)): return 'utf-16' if bstartswith(codecs.BOM_UTF8): return 'utf-8-sig' if len(b) >= 4: if not b[0]: # 00 00 -- -- - utf-32-be # 00 XX -- -- - utf-16-be return 'utf-16-be' if b[1] else 'utf-32-be' if not b[1]: # XX 00 00 00 - utf-32-le # XX 00 00 XX - utf-16-le # XX 00 XX -- - utf-16-le return 'utf-16-le' if b[2] or b[3] else 'utf-32-le' elif len(b) == 2: if not b[0]: # 00 XX - utf-16-be return 'utf-16-be' if not b[1]: # XX 00 - utf-16-le return 'utf-16-le' # default return 'utf-8' def load(fp, *, cls=None, object_hook=None, parse_float=None, parse_int=None, parse_constant=None, object_pairs_hook=None, **kw): """Deserialize ``fp`` (a ``.read()``-supporting file-like object containing a JSON document) to a Python object. ``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). ``object_pairs_hook`` is an optional function that will be called with the result of any object literal decoded with an ordered list of pairs. The return value of ``object_pairs_hook`` will be used instead of the ``dict``. This feature can be used to implement custom decoders. If ``object_hook`` is also defined, the ``object_pairs_hook`` takes priority. To use a custom ``JSONDecoder`` subclass, specify it with the ``cls`` kwarg; otherwise ``JSONDecoder`` is used. """ return loads(fp.read(), cls=cls, object_hook=object_hook, parse_float=parse_float, parse_int=parse_int, parse_constant=parse_constant, object_pairs_hook=object_pairs_hook, **kw) def loads(s, *, cls=None, object_hook=None, parse_float=None, parse_int=None, parse_constant=None, object_pairs_hook=None, **kw): """Deserialize ``s`` (a ``str``, ``bytes`` or ``bytearray`` instance containing a JSON document) to a Python object. ``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). ``object_pairs_hook`` is an optional function that will be called with the result of any object literal decoded with an ordered list of pairs. The return value of ``object_pairs_hook`` will be used instead of the ``dict``. This feature can be used to implement custom decoders. If ``object_hook`` is also defined, the ``object_pairs_hook`` takes priority. ``parse_float``, if specified, will be called with the string of every JSON float to be decoded. By default this is equivalent to float(num_str). This can be used to use another datatype or parser for JSON floats (e.g. decimal.Decimal). ``parse_int``, if specified, will be called with the string of every JSON int to be decoded. By default this is equivalent to int(num_str). This can be used to use another datatype or parser for JSON integers (e.g. float). ``parse_constant``, if specified, will be called with one of the following strings: -Infinity, Infinity, NaN. This can be used to raise an exception if invalid JSON numbers are encountered. To use a custom ``JSONDecoder`` subclass, specify it with the ``cls`` kwarg; otherwise ``JSONDecoder`` is used. """ if isinstance(s, str): if s.startswith('\ufeff'): raise JSONDecodeError("Unexpected UTF-8 BOM (decode using utf-8-sig)", s, 0) else: if not isinstance(s, (bytes, bytearray)): raise TypeError(f'the JSON object must be str, bytes or bytearray, ' f'not {s.__class__.__name__}') s = s.decode(detect_encoding(s), 'surrogatepass') if (cls is None and object_hook is None and parse_int is None and parse_float is None and parse_constant is None and object_pairs_hook is None and not kw): return _default_decoder.decode(s) if cls is None: cls = JSONDecoder if object_hook is not None: kw['object_hook'] = object_hook if object_pairs_hook is not None: kw['object_pairs_hook'] = object_pairs_hook if parse_float is not None: kw['parse_float'] = parse_float if parse_int is not None: kw['parse_int'] = parse_int if parse_constant is not None: kw['parse_constant'] = parse_constant return cls(**kw).decode(s)