import collections
+import functools
+import io
+import struct
TAG_NULL = 0x00
TAG_TRUE = 0x01
TAG_FALSE = 0x02
+TAG_UINT8 = 0x03
+TAG_UINT16 = 0x04
+TAG_UINT32 = 0x05
+TAG_UINT64 = 0x06
+TAG_INT8 = 0x10
+TAG_INT16 = 0x11
+TAG_INT32 = 0x12
+TAG_INT64 = 0x13
+TAG_BINARY = 0x20
+TAG_UTF8 = 0x21
+TAG_UTF16 = 0x22
+TAG_UTF32 = 0x23
TaggedObject = collections.namedtuple(
'TaggedObject',
return serializer
+def _make_struct_serializer(fmt):
+ fmt = '!B' + fmt
+ packer = functools.partial(struct.pack, fmt)
+
+ def serializer(to):
+ return packer(to.tag, to.instance)
+
+ return serializer
+
+def _make_string_serializer(encoder):
+ packer = functools.partial(struct.pack, '!BI')
+
+ def serializer(to):
+ encoded = encoder(to.instance)
+ return packer(to.tag, len(encoded)) + encoded
+
+ return serializer
+
_TAGS_TO_SERIALIZERS = {
TAG_NULL: _make_tag_only_serializer(TAG_NULL, None),
TAG_TRUE: _make_tag_only_serializer(TAG_TRUE, True),
TAG_FALSE: _make_tag_only_serializer(TAG_FALSE, False),
+ TAG_UINT8: _make_struct_serializer('B'),
+ TAG_UINT16: _make_struct_serializer('H'),
+ TAG_UINT32: _make_struct_serializer('I'),
+ TAG_UINT64: _make_struct_serializer('Q'),
+ TAG_INT8: _make_struct_serializer('b'),
+ TAG_INT16: _make_struct_serializer('h'),
+ TAG_INT32: _make_struct_serializer('i'),
+ TAG_INT64: _make_struct_serializer('q'),
+ TAG_BINARY: _make_string_serializer(lambda s: s),
+ TAG_UTF8: _make_string_serializer(lambda s: s.encode('utf-8')),
+ TAG_UTF16: _make_string_serializer(lambda s: s.encode('utf-16')),
+ TAG_UTF32: _make_string_serializer(lambda s: s.encode('utf-32')),
}
def serialize(to):
def _make_tag_only_parser(tag, value):
def parser(b):
- return TaggedObject(tag = tag, instance = value), b
+ return TaggedObject(tag = tag, instance = value)
+
+ return parser
+
+def _make_struct_deserializer(tag, fmt):
+ fmt = '!' + fmt
+ size = struct.calcsize(fmt)
+ unpacker = functools.partial(struct.unpack, fmt)
+
+ def parser(b):
+ b = b.read(size)
+ assert len(b) == size
+ return TaggedObject(tag = tag, instance = unpacker(b)[0])
+
+ return parser
+
+def _make_string_deserializer(tag, decoder):
+ fmt = '!I'
+ size = struct.calcsize(fmt)
+ unpacker = functools.partial(struct.unpack, fmt)
+
+ def parser(b):
+ length_b = b.read(size)
+ assert len(length_b) == size
+ length = unpacker(length_b)[0]
+ s = b.read(length)
+ assert len(s) == length
+ return TaggedObject(tag = tag, instance = decoder(s))
return parser
TAG_NULL: _make_tag_only_parser(TAG_NULL, None),
TAG_TRUE: _make_tag_only_parser(TAG_TRUE, True),
TAG_FALSE: _make_tag_only_parser(TAG_FALSE, False),
+ TAG_UINT8: _make_struct_deserializer(TAG_UINT8, 'B'),
+ TAG_UINT16: _make_struct_deserializer(TAG_UINT16, 'H'),
+ TAG_UINT32: _make_struct_deserializer(TAG_UINT32, 'I'),
+ TAG_UINT64: _make_struct_deserializer(TAG_UINT64, 'Q'),
+ TAG_INT8: _make_struct_deserializer(TAG_INT8, 'b'),
+ TAG_INT16: _make_struct_deserializer(TAG_INT16, 'h'),
+ TAG_INT32: _make_struct_deserializer(TAG_INT32, 'i'),
+ TAG_INT64: _make_struct_deserializer(TAG_INT64, 'q'),
+ TAG_BINARY: _make_string_deserializer(TAG_BINARY, lambda b: b),
+ TAG_UTF8: _make_string_deserializer(TAG_UTF8, lambda b: b.decode('utf-8')),
+ TAG_UTF16: _make_string_deserializer(TAG_UTF16, lambda b: b.decode('utf-16')),
+ TAG_UTF32: _make_string_deserializer(TAG_UTF32, lambda b: b.decode('utf-32')),
}
def deserialize(b):
- result, remainder = _TAGS_TO_PARSERS[b[0]](b[1:])
+ if isinstance(b, bytes):
+ b = io.BytesIO(b)
+
+ tag = b.read(1)[0]
+
+ result = _TAGS_TO_PARSERS[tag](b)
+
+ remainder = b.read()
if len(remainder) == 0:
return result