7 def _make_tag_only_serializer(tag, expected_value):
11 assert to.instance == expected_value
16 def _make_struct_serializer(fmt):
18 packer = functools.partial(struct.pack, fmt)
21 return packer(to.tag, to.instance)
25 def _make_string_serializer(encoder):
26 packer = functools.partial(struct.pack, '!BI')
29 encoded = encoder(to.instance)
30 return packer(to.tag, len(encoded)) + encoded
34 def _serialize_tuple(to):
35 assert isinstance(to.instance, tuple)
37 payload = b''.join(serialize(item) for item in to.instance)
41 return struct.pack('!BI', tags.TUPLE, len(payload)) + payload
44 _TAGS_TO_SERIALIZERS = {
45 tags.NULL: _make_tag_only_serializer(tags.NULL, None),
46 tags.TRUE: _make_tag_only_serializer(tags.TRUE, True),
47 tags.FALSE: _make_tag_only_serializer(tags.FALSE, False),
48 tags.UINT8: _make_struct_serializer('B'),
49 tags.UINT16: _make_struct_serializer('H'),
50 tags.UINT32: _make_struct_serializer('I'),
51 tags.UINT64: _make_struct_serializer('Q'),
52 tags.INT8: _make_struct_serializer('b'),
53 tags.INT16: _make_struct_serializer('h'),
54 tags.INT32: _make_struct_serializer('i'),
55 tags.INT64: _make_struct_serializer('q'),
56 tags.BINARY: _make_string_serializer(lambda s: s),
57 tags.UTF8: _make_string_serializer(lambda s: s.encode('utf-8')),
58 tags.UTF16: _make_string_serializer(lambda s: s.encode('utf-16')),
59 tags.UTF32: _make_string_serializer(lambda s: s.encode('utf-32')),
60 tags.TUPLE: _serialize_tuple,
64 return _TAGS_TO_SERIALIZERS[to.tag](to)
66 def _make_tag_only_parser(tag, value):
68 return 0, tags.TaggedObject(tag = tag, instance = value)
72 def _make_struct_deserializer(tag, fmt):
74 size = struct.calcsize(fmt)
75 unpacker = functools.partial(struct.unpack, fmt)
80 return size, tags.TaggedObject(tag = tag, instance = unpacker(b)[0])
85 _LENGTH_FMT_SIZE = struct.calcsize(_LENGTH_FMT)
87 def _read_length_then_payload(b):
88 length_b = b.read(_LENGTH_FMT_SIZE)
89 assert len(length_b) == _LENGTH_FMT_SIZE
90 length = struct.unpack(_LENGTH_FMT, length_b)[0]
92 payload = b.read(length)
93 assert len(payload) == length
94 return _LENGTH_FMT_SIZE + length, payload
96 def _make_string_deserializer(tag, decoder):
98 size = struct.calcsize(fmt)
99 unpacker = functools.partial(struct.unpack, fmt)
102 bytes_read, payload = _read_length_then_payload(b)
103 return bytes_read, tags.TaggedObject(tag = tag, instance = decoder(payload))
107 def _deserialize_tuple(b):
108 bytes_read, payload = _read_length_then_payload(b)
110 payload_stream = io.BytesIO(payload)
115 while total_bytes_read < len(payload):
116 partial_bytes_read, item = _deserialize_partial(payload_stream)
117 total_bytes_read += partial_bytes_read
118 instance.append(item)
120 return bytes_read, tags.TaggedObject(tag = tags.TUPLE, instance = tuple(instance))
123 tags.NULL: _make_tag_only_parser(tags.NULL, None),
124 tags.TRUE: _make_tag_only_parser(tags.TRUE, True),
125 tags.FALSE: _make_tag_only_parser(tags.FALSE, False),
126 tags.UINT8: _make_struct_deserializer(tags.UINT8, 'B'),
127 tags.UINT16: _make_struct_deserializer(tags.UINT16, 'H'),
128 tags.UINT32: _make_struct_deserializer(tags.UINT32, 'I'),
129 tags.UINT64: _make_struct_deserializer(tags.UINT64, 'Q'),
130 tags.INT8: _make_struct_deserializer(tags.INT8, 'b'),
131 tags.INT16: _make_struct_deserializer(tags.INT16, 'h'),
132 tags.INT32: _make_struct_deserializer(tags.INT32, 'i'),
133 tags.INT64: _make_struct_deserializer(tags.INT64, 'q'),
134 tags.BINARY: _make_string_deserializer(tags.BINARY, lambda b: b),
135 tags.UTF8: _make_string_deserializer(tags.UTF8, lambda b: b.decode('utf-8')),
136 tags.UTF16: _make_string_deserializer(tags.UTF16, lambda b: b.decode('utf-16')),
137 tags.UTF32: _make_string_deserializer(tags.UTF32, lambda b: b.decode('utf-32')),
138 tags.TUPLE: _deserialize_tuple,
141 def _deserialize_partial(b):
144 bytes_read, to = _TAGS_TO_PARSERS[tag[0]](b)
145 return bytes_read + 1, to
148 if isinstance(b, bytes):
151 bytes_read, result = _deserialize_partial(b)
155 if len(remainder) == 0:
158 raise Exception('Unable to parse remainder: {}'.format(remainder))