r""" A simple, fast, extensible JSON encoder and decoder JSON (JavaScript Object Notation) is a subset of JavaScript syntax (ECMA-262 3rd edition) used as a lightweight data interchange format. simplejson exposes an API familiar to uses of the standard library marshal and pickle modules. Encoding basic Python object hierarchies:: >>> import simplejson >>> simplejson.dumps(['foo', {'bar': ('baz', None, 1.0, 2)}]) '["foo", {"bar": ["baz", null, 1.0, 2]}]' >>> print simplejson.dumps("\"foo\bar") "\"foo\bar" >>> print simplejson.dumps(u'\u1234') "\u1234" >>> print simplejson.dumps('\\') "\\" >>> print simplejson.dumps({"c": 0, "b": 0, "a": 0}, sort_keys=True) {"a": 0, "b": 0, "c": 0} >>> from StringIO import StringIO >>> io = StringIO() >>> simplejson.dump(['streaming API'], io) >>> io.getvalue() '["streaming API"]' Decoding JSON:: >>> import simplejson >>> simplejson.loads('["foo", {"bar":["baz", null, 1.0, 2]}]') [u'foo', {u'bar': [u'baz', None, 1.0, 2]}] >>> simplejson.loads('"\\"foo\\bar"') u'"foo\x08ar' >>> from StringIO import StringIO >>> io = StringIO('["streaming API"]') >>> simplejson.load(io) [u'streaming API'] Specializing JSON object decoding:: >>> import simplejson >>> def as_complex(dct): ... if '__complex__' in dct: ... return complex(dct['real'], dct['imag']) ... return dct ... >>> simplejson.loads('{"__complex__": true, "real": 1, "imag": 2}', ... object_hook=as_complex) (1+2j) Extending JSONEncoder:: >>> import simplejson >>> class ComplexEncoder(simplejson.JSONEncoder): ... def default(self, obj): ... if isinstance(obj, complex): ... return [obj.real, obj.imag] ... return simplejson.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', ']'] Note that the JSON produced by this module is a subset of YAML, so it may be used as a serializer for that as well. """ __version__ = '1.3' __all__ = [ 'dump', 'dumps', 'load', 'loads', 'JSONDecoder', 'JSONEncoder', ] from django.utils.simplejson.decoder import JSONDecoder from django.utils.simplejson.encoder import JSONEncoder def dump(obj, fp, skipkeys=False, ensure_ascii=True, check_circular=True, allow_nan=True, cls=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``). To use a custom ``JSONEncoder`` subclass (e.g. one that overrides the ``.default()`` method to serialize additional types), specify it with the ``cls`` kwarg. """ if cls is None: cls = JSONEncoder iterable = cls(skipkeys=skipkeys, ensure_ascii=ensure_ascii, check_circular=check_circular, allow_nan=allow_nan, **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, **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``). To use a custom ``JSONEncoder`` subclass (e.g. one that overrides the ``.default()`` method to serialize additional types), specify it with the ``cls`` kwarg. """ if cls is None: cls = JSONEncoder return cls(skipkeys=skipkeys, ensure_ascii=ensure_ascii, check_circular=check_circular, allow_nan=allow_nan, **kw).encode(obj) def load(fp, encoding=None, cls=None, object_hook=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. """ if cls is None: cls = JSONDecoder if object_hook is not None: kw['object_hook'] = object_hook return cls(encoding=encoding, **kw).decode(fp.read()) def loads(s, encoding=None, cls=None, object_hook=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). To use a custom ``JSONDecoder`` subclass, specify it with the ``cls`` kwarg. """ if cls is None: cls = JSONDecoder if object_hook is not None: kw['object_hook'] = object_hook return cls(encoding=encoding, **kw).decode(s) def read(s): """ json-py API compatibility hook. Use loads(s) instead. """ import warnings warnings.warn("simplejson.loads(s) should be used instead of read(s)", DeprecationWarning) return loads(s) def write(obj): """ json-py API compatibility hook. Use dumps(s) instead. """ import warnings warnings.warn("simplejson.dumps(s) should be used instead of write(s)", DeprecationWarning) return dumps(obj)