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

  Fix JSON module docs.
........
  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
........

3 files changed, 424 insertions, 0 deletions

diff --git a/Doc/library/json.rst b/Doc/library/json.rst
new file mode 100644
index 0000000..a0a62d1
--- /dev/null
+++ b/Doc/library/json.rst
@@ -0,0 +1,397 @@
+:mod:`json` --- JSON encoder and decoder
+========================================
+
+.. module:: json
+   :synopsis: Encode and decode the JSON format.
+.. moduleauthor:: Bob Ippolito <bob@redivi.com>
+.. sectionauthor:: Bob Ippolito <bob@redivi.com>
+.. versionadded:: 2.6
+
+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.
+
+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(u'\u1234')
+    "\u1234"
+    >>> print json.dumps('\\')
+    "\\"
+    >>> print json.dumps({"c": 0, "b": 0, "a": 0}, sort_keys=True)
+    {"a": 0, "b": 0, "c": 0}
+    >>> from StringIO 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::
+
+    >>> import json
+    >>> print json.dumps({'4': 5, '6': 7}, sort_keys=True, indent=4)
+    {
+        "4": 5, 
+        "6": 7
+    }
+
+Decoding JSON::
+    
+    >>> import json
+    >>> json.loads('["foo", {"bar":["baz", null, 1.0, 2]}]')
+    [u'foo', {u'bar': [u'baz', None, 1.0, 2]}]
+    >>> json.loads('"\\"foo\\bar"')
+    u'"foo\x08ar'
+    >>> from StringIO import StringIO
+    >>> io = StringIO('["streaming API"]')
+    >>> json.load(io)
+    [u'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 :class:`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', ']']
+    
+
+.. highlight:: none
+
+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)
+
+.. highlight:: python
+
+.. note:: 
+
+   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.
+
+
+Basic Usage
+-----------
+
+.. function:: dump(obj, fp[, skipkeys[, ensure_ascii[, check_circular[, allow_nan[, cls[, indent[, separators[, encoding[, default[, **kw]]]]]]]]]])
+
+   Serialize *obj* as a JSON formatted stream to *fp* (a ``.write()``-supporting
+   file-like object).
+
+   If *skipkeys* is ``True`` (default: ``False``), then dict keys that are not
+   of a basic type (:class:`str`, :class:`unicode`, :class:`int`, :class:`long`,
+   :class:`float`, :class:`bool`, ``None``) will be skipped instead of raising a
+   :exc:`TypeError`.
+
+   If *ensure_ascii* is ``False`` (default: ``True``), then some chunks written
+   to *fp* may be :class:`unicode` instances, subject to normal Python
+   :class:`str` to :class:`unicode` coercion rules.  Unless ``fp.write()``
+   explicitly understands :class:`unicode` (as in :func:`codecs.getwriter`) this
+   is likely to cause an error.
+
+   If *check_circular* is ``False`` (default: ``True``), then the circular
+   reference check for container types will be skipped and a circular reference
+   will result in an :exc:`OverflowError` (or worse).
+
+   If *allow_nan* is ``False`` (default: ``True``), then it will be a
+   :exc:`ValueError` to serialize out of range :class:`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`` (the default) selects 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 :exc:`TypeError`.  The default simply raises :exc:`TypeError`.
+
+   To use a custom :class:`JSONEncoder`` subclass (e.g. one that overrides the
+   :meth:`default` method to serialize additional types), specify it with the
+   *cls* kwarg.
+
+
+.. function:: dumps(obj[, skipkeys[, ensure_ascii[, check_circular[, allow_nan[, cls[, indent[, separators[, encoding[, default[, **kw]]]]]]]]]])
+
+   Serialize *obj* to a JSON formatted :class:`str`.
+
+   If *ensure_ascii* is ``False``, then the return value will be a
+   :class:`unicode` instance.  The other arguments have the same meaning as in
+   :func:`dump`.
+
+
+.. function load(fp[, encoding[, cls[, object_hook[, parse_float[, parse_int[, parse_constant[, **kw]]]]]]])
+
+   Deserialize *fp* (a ``.read()``-supporting file-like object containing a JSON
+   document) to a Python object.
+
+   If the contents of *fp* are 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 :class:`unicode` object and passed to :func:`loads`.
+
+   *object_hook* is an optional function that will be called with the result of
+   any object literal decode (a :class:`dict`).  The return value of
+   *object_hook* will be used instead of the :class:`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. :class:`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. :class:`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 :class:`JSONDecoder` subclass, specify it with the ``cls``
+   kwarg.  Additional keyword arguments will be passed to the constructor of the
+   class.
+
+
+.. function loads(s[, encoding[, cls[, object_hook[, parse_float[, parse_int[, parse_constant[, **kw]]]]]]])
+
+   Deserialize *s* (a :class:`str` or :class:`unicode` instance containing a JSON
+   document) to a Python object.
+
+   If *s* is a :class:`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 :class:`unicode` first.
+
+   The other arguments have the same meaning as in :func:`dump`.
+
+
+Encoders and decoders
+---------------------
+
+.. class:: JSONDecoder([encoding[, object_hook[, parse_float[, parse_int[, parse_constant[, strict]]]]]])
+
+   Simple JSON decoder.
+
+   Performs the following translations in decoding by default:
+
+   +---------------+-------------------+
+   | JSON          | Python            |
+   +===============+===================+
+   | object        | dict              |
+   +---------------+-------------------+
+   | array         | list              |
+   +---------------+-------------------+
+   | string        | unicode           |
+   +---------------+-------------------+
+   | number (int)  | int, long         |
+   +---------------+-------------------+
+   | number (real) | float             |
+   +---------------+-------------------+
+   | true          | True              |
+   +---------------+-------------------+
+   | false         | False             |
+   +---------------+-------------------+
+   | null          | None              |
+   +---------------+-------------------+
+
+   It also understands ``NaN``, ``Infinity``, and ``-Infinity`` as their
+   corresponding ``float`` values, which is outside the JSON spec.
+
+   *encoding* determines the encoding used to interpret any :class:`str` objects
+   decoded by this instance (UTF-8 by default).  It has no effect when decoding
+   :class:`unicode` objects.
+
+   Note that currently only encodings that are a superset of ASCII work, strings
+   of other encodings should be passed in as :class:`unicode`.
+
+   *object_hook*, if specified, will be called with the result of every JSON
+   object decoded and its return value will be used in place of the given
+   :class:`dict`.  This can be used to provide custom deserializations (e.g. to
+   support 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. :class:`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. :class:`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.
+
+
+   .. method:: decode(s)
+
+      Return the Python representation of *s* (a :class:`str` or
+      :class:`unicode` instance containing a JSON document)
+
+   .. method:: raw_decode(s)
+
+      Decode a JSON document from *s* (a :class:`str` or :class:`unicode`
+      beginning with a JSON document) and return a 2-tuple of the Python
+      representation and the index in *s* where the document ended.
+
+      This can be used to decode a JSON document from a string that may have
+      extraneous data at the end.
+
+
+.. class:: JSONEncoder([skipkeys[, ensure_ascii[, check_circular[, allow_nan[, sort_keys[, indent[, separators[, encoding[, default]]]]]]]]])
+
+   Extensible JSON encoder for Python data structures.
+
+   Supports the following objects and types by default:
+
+   +-------------------+---------------+
+   | Python            | JSON          |
+   +===================+===============+
+   | dict              | object        |
+   +-------------------+---------------+
+   | list, tuple       | array         |
+   +-------------------+---------------+
+   | str, unicode      | string        |
+   +-------------------+---------------+
+   | int, long, float  | number        |
+   +-------------------+---------------+
+   | True              | true          |
+   +-------------------+---------------+
+   | False             | false         |
+   +-------------------+---------------+
+   | None              | null          |
+   +-------------------+---------------+
+
+   To extend this to recognize other objects, subclass and implement a
+   :meth:`default` method with another method that returns a serializable object
+   for ``o`` if possible, otherwise it should call the superclass implementation
+   (to raise :exc:`TypeError`).
+
+   If *skipkeys* is ``False`` (the default), then it is a :exc:`TypeError` to
+   attempt encoding of keys that are not str, int, long, float or None.  If
+   *skipkeys* is ``True``, such items are simply skipped.
+
+   If *ensure_ascii* is ``True`` (the default), the output is guaranteed to be
+   :class:`str` objects with all incoming unicode characters escaped.  If
+   *ensure_ascii* is ``False``, the output will be a unicode object.
+
+   If *check_circular* is ``True`` (the default), then lists, dicts, and custom
+   encoded objects will be checked for circular references during encoding to
+   prevent an infinite recursion (which would cause an :exc:`OverflowError`).
+   Otherwise, no such check takes place.
+
+   If *allow_nan* is ``True`` (the default), then ``NaN``, ``Infinity``, and
+   ``-Infinity`` will be encoded as such.  This behavior is not JSON
+   specification compliant, but is consistent with most JavaScript based
+   encoders and decoders.  Otherwise, it will be a :exc:`ValueError` to encode
+   such floats.
+
+   If *sort_keys* is ``True`` (the default), then the output of dictionaries
+   will be sorted by key; this is useful for regression tests to ensure that
+   JSON serializations can be compared on a day-to-day basis.
+
+   If *indent* is a non-negative integer (it is ``None`` by default), 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 ``(', ', ': ')``.  To get the most compact JSON
+   representation, you should specify ``(',', ':')`` to eliminate whitespace.
+
+   If specified, *default* is a function that gets called for objects that can't
+   otherwise be serialized.  It should return a JSON encodable version of the
+   object or raise a :exc:`TypeError`.
+
+   If *encoding* is not ``None``, then all input strings will be transformed
+   into unicode using that encoding prior to JSON-encoding.  The default is
+   UTF-8.
+
+
+   .. method:: default(o)
+
+      Implement this method in a subclass such that it returns a serializable
+      object for *o*, or calls the base implementation (to raise a
+      :exc:`TypeError`).
+
+      For example, to support arbitrary iterators, you could implement default
+      like this::
+            
+         def default(self, o):
+            try:
+               iterable = iter(o)
+            except TypeError:
+               pass
+            else:
+                return list(iterable)
+            return JSONEncoder.default(self, o)
+
+
+   .. method:: encode(o)
+
+      Return a JSON string representation of a Python data structure, *o*.  For
+      example::
+
+        >>> JSONEncoder().encode({"foo": ["bar", "baz"]})
+        '{"foo": ["bar", "baz"]}'
+
+
+   .. method:: iterencode(o)
+
+      Encode the given object, *o*, and yield each string representation as
+      available.  For example::
+            
+            for chunk in JSONEncoder().iterencode(bigobject):
+                mysocket.write(chunk)
diff --git a/Doc/library/netdata.rst b/Doc/library/netdata.rst
index add01d2..2f27189 100644
--- a/Doc/library/netdata.rst
+++ b/Doc/library/netdata.rst
@@ -12,6 +12,7 @@ on the Internet.
 .. toctree::
 
    email.rst
+   json.rst
    mailcap.rst
    mailbox.rst
    mhlib.rst
diff --git a/Doc/whatsnew/2.6.rst b/Doc/whatsnew/2.6.rst
index 8bd0c19..1af6f73 100644
--- a/Doc/whatsnew/2.6.rst
+++ b/Doc/whatsnew/2.6.rst
@@ -1210,6 +1210,7 @@ Mullender that was in Python's :file:`Demo/classes/` directory for a
 long time.  This implementation was significantly updated by Jeffrey
 Yasskin.
 
+
 Other Language Changes
 ======================
 
@@ -2146,6 +2147,31 @@ complete list of changes, or look through the CVS logs for all the details.
 .. ======================================================================
 .. whole new modules get described in subsections here
 
+The :mod:`json` module
+----------------------
+
+The new :mod:`json` module supports the encoding and decoding of Python types in
+JSON (Javascript Object Notation). JSON is a lightweight interchange format
+often used in web applications. For more information about JSON, see
+http://www.json.org.
+
+:mod:`json` comes with support for decoding and encoding most builtin Python
+types. The following example encodes and decodes a dictionary::
+
+       >>> import json
+       >>> data = {"spam" : "foo", "parrot" : 42}
+       >>> in_json = json.dumps(data) # Encode the data
+       >>> in_json
+       '{"parrot": 42, "spam": "foo"}'
+       >>> json.loads(in_json) # Decode into a Python object
+       {"spam" : "foo", "parrot" : 42}
+
+It is also possible to write your own decoders and encoders to support more
+types. Pretty-printing of the JSON strings is also supported.
+
+:mod:`json` (originally called simplejson) was written by Bob Ippolito.
+
+
 Improved SSL Support
 --------------------------------------------------