from django.utils import simplejson from django.utils.simplejson.encoder import ( encode_basestring, encode_basestring_ascii, FLOAT_REPR, INFINITY) from types import GeneratorType class JSONEncoder(simplejson.JSONEncoder): def iterencode(self, o, _one_shot=False): """Encode the given object and yield each string representation as available. For example:: for chunk in JSONEncoder().iterencode(bigobject): mysocket.write(chunk) This method is a verbatim copy of :meth:`django.utils.simplejson.encoder.JSONEncoder.iterencode`. It is needed because we need to call our patched :func:`streamingjson._make_iterencode`. """ if self.check_circular: markers = {} else: markers = None if self.ensure_ascii: _encoder = encode_basestring_ascii else: _encoder = encode_basestring if self.encoding != 'utf-8': def _encoder(o, _orig_encoder=_encoder, _encoding=self.encoding): if isinstance(o, str): o = o.decode(_encoding) return _orig_encoder(o) def floatstr(o, allow_nan=self.allow_nan, _repr=FLOAT_REPR, _inf=INFINITY, _neginf=-INFINITY): # Check for specials. Note that this type of test is processor- and/or # platform-specific, so do tests which don't depend on the internals. if o != o: text = 'NaN' elif o == _inf: text = 'Infinity' elif o == _neginf: text = '-Infinity' else: return _repr(o) if not allow_nan: raise ValueError("Out of range float values are not JSON compliant: %r" % (o,)) return text _iterencode = _make_iterencode( markers, self.default, _encoder, self.indent, floatstr, self.key_separator, self.item_separator, self.sort_keys, self.skipkeys, _one_shot) return _iterencode(o, 0) def _make_iterencode(markers, _default, _encoder, _indent, _floatstr, _key_separator, _item_separator, _sort_keys, _skipkeys, _one_shot, ## HACK: hand-optimized bytecode; turn globals into locals False=False, True=True, ValueError=ValueError, basestring=basestring, dict=dict, float=float, GeneratorType=GeneratorType, id=id, int=int, isinstance=isinstance, list=list, long=long, str=str, tuple=tuple, ): """ This is a patched version of :func:`django.utils.simplejson.encoder.iterencode`. Whenever it encounters a generator in the data structure, it encodes it as a JSON list. """ def _iterencode_list(lst, _current_indent_level): if not lst: yield '[]' return if markers is not None: markerid = id(lst) if markerid in markers: raise ValueError("Circular reference detected") markers[markerid] = lst buf = '[' if _indent is not None: _current_indent_level += 1 newline_indent = '\n' + (' ' * (_indent * _current_indent_level)) separator = _item_separator + newline_indent buf += newline_indent else: newline_indent = None separator = _item_separator first = True for value in lst: if first: first = False else: buf = separator if isinstance(value, basestring): yield buf + _encoder(value) elif value is None: yield buf + 'null' elif value is True: yield buf + 'true' elif value is False: yield buf + 'false' elif isinstance(value, (int, long)): yield buf + str(value) elif isinstance(value, float): yield buf + _floatstr(value) else: yield buf if isinstance(value, (list, tuple, GeneratorType)): chunks = _iterencode_list(value, _current_indent_level) elif isinstance(value, dict): chunks = _iterencode_dict(value, _current_indent_level) else: chunks = _iterencode(value, _current_indent_level) for chunk in chunks: yield chunk if newline_indent is not None: _current_indent_level -= 1 yield '\n' + (' ' * (_indent * _current_indent_level)) yield ']' if markers is not None: del markers[markerid] def _iterencode_dict(dct, _current_indent_level): if not dct: yield '{}' return if markers is not None: markerid = id(dct) if markerid in markers: raise ValueError("Circular reference detected") markers[markerid] = dct yield '{' if _indent is not None: _current_indent_level += 1 newline_indent = '\n' + (' ' * (_indent * _current_indent_level)) item_separator = _item_separator + newline_indent yield newline_indent else: newline_indent = None item_separator = _item_separator first = True if _sort_keys: items = dct.items() items.sort(key=lambda kv: kv[0]) else: items = dct.iteritems() for key, value in items: if isinstance(key, basestring): pass # JavaScript is weakly typed for these, so it makes sense to # also allow them. Many encoders seem to do something like this. elif isinstance(key, float): key = _floatstr(key) elif isinstance(key, (int, long)): key = str(key) elif key is True: key = 'true' elif key is False: key = 'false' elif key is None: key = 'null' elif _skipkeys: continue else: raise TypeError("key %r is not a string" % (key,)) if first: first = False else: yield item_separator yield _encoder(key) yield _key_separator if isinstance(value, basestring): yield _encoder(value) elif value is None: yield 'null' elif value is True: yield 'true' elif value is False: yield 'false' elif isinstance(value, (int, long)): yield str(value) elif isinstance(value, float): yield _floatstr(value) else: if isinstance(value, (list, tuple, GeneratorType)): chunks = _iterencode_list(value, _current_indent_level) elif isinstance(value, dict): chunks = _iterencode_dict(value, _current_indent_level) else: chunks = _iterencode(value, _current_indent_level) for chunk in chunks: yield chunk if newline_indent is not None: _current_indent_level -= 1 yield '\n' + (' ' * (_indent * _current_indent_level)) yield '}' if markers is not None: del markers[markerid] def _iterencode(o, _current_indent_level): if isinstance(o, basestring): yield _encoder(o) elif o is None: yield 'null' elif o is True: yield 'true' elif o is False: yield 'false' elif isinstance(o, (int, long)): yield str(o) elif isinstance(o, float): yield _floatstr(o) elif isinstance(o, (list, tuple, GeneratorType)): for chunk in _iterencode_list(o, _current_indent_level): yield chunk elif isinstance(o, dict): for chunk in _iterencode_dict(o, _current_indent_level): yield chunk else: if markers is not None: markerid = id(o) if markerid in markers: raise ValueError("Circular reference detected") markers[markerid] = o o = _default(o) for chunk in _iterencode(o, _current_indent_level): yield chunk if markers is not None: del markers[markerid] return _iterencode