Merged revisions 62734,62736,62748,62769 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

........
  r62734 | brett.cannon | 2008-05-05 22:21:38 +0200 (Mon, 05 May 2008) | 5 lines

  Add the 'json' package. Code taken from simplejson 1.9 and contributed by Bob
  Ippolito.

  Closes issue #2750.
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  r62736 | georg.brandl | 2008-05-05 22:53:39 +0200 (Mon, 05 May 2008) | 2 lines

  Fix JSON module docs.
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  r62748 | benjamin.peterson | 2008-05-06 04:51:10 +0200 (Tue, 06 May 2008) | 2 lines

  PEP 8 nits in json package
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  r62769 | christian.heimes | 2008-05-06 18:18:41 +0200 (Tue, 06 May 2008) | 2 lines

  Intern static string
  Use float constructors instead of magic code for float constants
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1 files changed, 318 insertions, 0 deletions

diff --git a/Lib/json/__init__.py b/Lib/json/__init__.py
new file mode 100644
index 0000000..c419c78
--- /dev/null
+++ b/Lib/json/__init__.py
@@ -0,0 +1,318 @@
+r"""A simple, fast, extensible JSON encoder and decoder
+
+JSON (JavaScript Object Notation) <http://json.org> is a subset of
+JavaScript syntax (ECMA-262 3rd edition) used as a lightweight data
+interchange format.
+
+json exposes an API familiar to uses of the standard library
+marshal and pickle modules.
+
+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
+    >>> json.dumps([1,2,3,{'4': 5, '6': 7}], separators=(',',':'))
+    '[1,2,3,{"4":5,"6":7}]'
+
+Pretty printing (using repr() because of extraneous whitespace in the output)::
+
+    >>> import json
+    >>> print(repr(json.dumps({'4': 5, '6': 7}, sort_keys=True, indent=4)))
+    '{\n    "4": 5, \n    "6": 7\n}'
+
+Decoding JSON::
+
+    >>> import json
+    >>> json.loads('["foo", {"bar":["baz", null, 1.0, 2]}]')
+    ['foo', {'bar': ['baz', None, 1.0, 2]}]
+    >>> json.loads('"\\"foo\\bar"')
+    '"foo\x08ar'
+    >>> from io import StringIO
+    >>> io = StringIO('["streaming API"]')
+    >>> json.load(io)
+    ['streaming API']
+
+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)
+    >>> import decimal
+    >>> json.loads('1.1', parse_float=decimal.Decimal)
+    Decimal('1.1')
+
+Extending JSONEncoder::
+
+    >>> import json
+    >>> class ComplexEncoder(json.JSONEncoder):
+    ...     def default(self, obj):
+    ...         if isinstance(obj, complex):
+    ...             return [obj.real, obj.imag]
+    ...         return json.JSONEncoder.default(self, obj)
+    ...
+    >>> dumps(2 + 1j, cls=ComplexEncoder)
+    '[2.0, 1.0]'
+    >>> ComplexEncoder().encode(2 + 1j)
+    '[2.0, 1.0]'
+    >>> list(ComplexEncoder().iterencode(2 + 1j))
+    ['[', '2.0', ', ', '1.0', ']']
+
+
+Using json.tool from the shell to validate and
+pretty-print::
+
+    $ echo '{"json":"obj"}' | python -mjson.tool
+    {
+        "json": "obj"
+    }
+    $ echo '{ 1.2:3.4}' | python -mjson.tool
+    Expecting property name: line 1 column 2 (char 2)
+
+Note that the JSON produced by this module's default settings
+is a subset of YAML, so it may be used as a serializer for that as well.
+
+"""
+
+__version__ = '1.9'
+__all__ = [
+    'dump', 'dumps', 'load', 'loads',
+    'JSONDecoder', 'JSONEncoder',
+]
+
+__author__ = 'Bob Ippolito <bob@redivi.com>'
+
+from .decoder import JSONDecoder
+from .encoder import JSONEncoder
+
+_default_encoder = JSONEncoder(
+    skipkeys=False,
+    ensure_ascii=True,
+    check_circular=True,
+    allow_nan=True,
+    indent=None,
+    separators=None,
+    encoding='utf-8',
+    default=None,
+)
+
+def dump(obj, fp, skipkeys=False, ensure_ascii=True, check_circular=True,
+        allow_nan=True, cls=None, indent=None, separators=None,
+        encoding='utf-8', default=None, **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``, ``unicode``, ``int``, ``long``, ``float``, ``bool``, ``None``)
+    will be skipped instead of raising a ``TypeError``.
+
+    If ``ensure_ascii`` is ``False``, then the some chunks written to ``fp``
+    may be ``unicode`` instances, subject to normal Python ``str`` to
+    ``unicode`` coercion rules. Unless ``fp.write()`` explicitly
+    understands ``unicode`` (as in ``codecs.getwriter()``) this is likely
+    to cause an error.
+
+    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 ``separators`` is an ``(item_separator, dict_separator)`` tuple
+    then it will be used instead of the default ``(', ', ': ')`` separators.
+    ``(',', ':')`` is the most compact JSON representation.
+
+    ``encoding`` is the character encoding for str instances, default is UTF-8.
+
+    ``default(obj)`` is a function that should return a serializable version
+    of obj or raise TypeError. The default simply raises TypeError.
+
+    To use a custom ``JSONEncoder`` subclass (e.g. one that overrides the
+    ``.default()`` method to serialize additional types), specify it with
+    the ``cls`` kwarg.
+
+    """
+    # cached encoder
+    if (skipkeys is False and ensure_ascii is True and
+        check_circular is True and allow_nan is True and
+        cls is None and indent is None and separators is None and
+        encoding == 'utf-8' and default is None 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, encoding=encoding,
+            default=default, **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,
+        encoding='utf-8', default=None, **kw):
+    """Serialize ``obj`` to a JSON formatted ``str``.
+
+    If ``skipkeys`` is ``True`` then ``dict`` keys that are not basic types
+    (``str``, ``unicode``, ``int``, ``long``, ``float``, ``bool``, ``None``)
+    will be skipped instead of raising a ``TypeError``.
+
+    If ``ensure_ascii`` is ``False``, then the return value will be a
+    ``unicode`` instance subject to normal Python ``str`` to ``unicode``
+    coercion rules instead of being escaped to an ASCII ``str``.
+
+    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 ``separators`` is an ``(item_separator, dict_separator)`` tuple
+    then it will be used instead of the default ``(', ', ': ')`` separators.
+    ``(',', ':')`` is the most compact JSON representation.
+
+    ``encoding`` is the character encoding for str instances, default is UTF-8.
+
+    ``default(obj)`` is a function that should return a serializable version
+    of obj or raise TypeError. The default simply raises TypeError.
+
+    To use a custom ``JSONEncoder`` subclass (e.g. one that overrides the
+    ``.default()`` method to serialize additional types), specify it with
+    the ``cls`` kwarg.
+
+    """
+    # cached encoder
+    if (skipkeys is False and ensure_ascii is True and
+        check_circular is True and allow_nan is True and
+        cls is None and indent is None and separators is None and
+        encoding == 'utf-8' and default is None 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, encoding=encoding, default=default,
+        **kw).encode(obj)
+
+
+_default_decoder = JSONDecoder(encoding=None, object_hook=None)
+
+
+def load(fp, encoding=None, cls=None, object_hook=None, parse_float=None,
+        parse_int=None, parse_constant=None, **kw):
+    """Deserialize ``fp`` (a ``.read()``-supporting file-like object
+    containing a JSON document) to a Python object.
+
+    If the contents of ``fp`` is encoded with an ASCII based encoding other
+    than utf-8 (e.g. latin-1), then an appropriate ``encoding`` name must
+    be specified. Encodings that are not ASCII based (such as UCS-2) are
+    not allowed, and should be wrapped with
+    ``codecs.getreader(fp)(encoding)``, or simply decoded to a ``unicode``
+    object and passed to ``loads()``
+
+    ``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).
+
+    To use a custom ``JSONDecoder`` subclass, specify it with the ``cls``
+    kwarg.
+
+    """
+    return loads(fp.read(),
+        encoding=encoding, cls=cls, object_hook=object_hook,
+        parse_float=parse_float, parse_int=parse_int,
+        parse_constant=parse_constant, **kw)
+
+
+def loads(s, encoding=None, cls=None, object_hook=None, parse_float=None,
+        parse_int=None, parse_constant=None, **kw):
+    """Deserialize ``s`` (a ``str`` or ``unicode`` instance containing a JSON
+    document) to a Python object.
+
+    If ``s`` is a ``str`` instance and is encoded with an ASCII based encoding
+    other than utf-8 (e.g. latin-1) then an appropriate ``encoding`` name
+    must be specified. Encodings that are not ASCII based (such as UCS-2)
+    are not allowed and should be decoded to ``unicode`` first.
+
+    ``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).
+
+    ``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, null, true, false.
+    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.
+
+    """
+    if (cls is None and encoding is None and object_hook is None and
+            parse_int is None and parse_float is None and
+            parse_constant 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 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(encoding=encoding, **kw).decode(s)