def unpack_from(cls, payload, expected_segments):
for num_segment in iter_range(expected_segments):
try:
segment_header = ReplySegmentHeader(*cls.header_struct.unpack(payload.read(cls.header_size)))
except struct.error:
raise Exception("No valid segment header")
debug('%s (%d/%d): %s', cls.__name__, num_segment + 1, expected_segments, str(segment_header))
if expected_segments == 1:
# If we just expects one segment than we can take the full payload.
# This also a workaround of an internal bug (Which bug?)
segment_payload_size = -1
else:
segment_payload_size = segment_header.segment_length - cls.header_size
# Determinate segment payload
pl = payload.read(segment_payload_size)
segment_payload = BytesIO(pl)
debug('Read %d bytes payload segment %d', len(pl), num_segment + 1)
parts = tuple(Part.unpack_from(segment_payload, expected_parts=segment_header.num_parts))
segment = cls(segment_header.function_code, parts, header=segment_header)
if segment_header.segment_kind == segment_kinds.REPLY:
yield segment
elif segment_header.segment_kind == segment_kinds.ERROR:
error = segment
if error.parts[0].kind == part_kinds.ROWSAFFECTED:
raise Exception("Rows affected %s" % (error.parts[0].values,))
elif error.parts[0].kind == part_kinds.ERROR:
raise error.parts[0].errors[0]
else:
raise Exception("Invalid reply segment")
def test_unpack_unkown_part_raises_exception():
packed = BytesIO(
b"\x80\x00\x0a\x00\x00\x00\x00\x00\x0a\x00\x00\x00\x00"
b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
)
with pytest.raises(InterfaceError):
tuple(Part.unpack_from(packed, 1))
def test_unpack_unkown_part_raises_exception(self):
packed = BytesIO(
b"\x80\x00\x0a\x00\x00\x00\x00\x00\x0a\x00\x00\x00\x00"
b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
)
with pytest.raises(InterfaceError):
tuple(Part.unpack_from(packed, 1))
def unpack(cls, header, payload):
"""
Takes unpacked header and payload of segment and
create ReplySegment object.
"""
return cls(
header[6],
tuple(Part.unpack_from(payload, expected_parts=header[2]))
)
def unpack_from(cls, payload, expected_segments):
for num_segment in iter_range(expected_segments):
try:
segment_header = ReplySegmentHeader(
*cls.header_struct.unpack(payload.read(cls.header_size)))
except struct.error:
raise Exception("No valid segment header")
debug('%s (%d/%d): %s', cls.__name__, num_segment + 1,
expected_segments, str(segment_header))
if expected_segments == 1:
# If we just expects one segment than we can take the full payload.
# This also a workaround of an internal bug (Which bug?)
segment_payload_size = -1
else:
segment_payload_size = segment_header.segment_length - cls.header_size
# Determinate segment payload
pl = payload.read(segment_payload_size)
segment_payload = BytesIO(pl)
debug('Read %d bytes payload segment %d', len(pl), num_segment + 1)
parts = tuple(
Part.unpack_from(segment_payload,
expected_parts=segment_header.num_parts))
segment = cls(segment_header.function_code,
parts,
header=segment_header)
if segment_header.segment_kind == segment_kinds.REPLY:
yield segment
elif segment_header.segment_kind == segment_kinds.ERROR:
error = segment
if error.parts[0].kind == part_kinds.ROWSAFFECTED:
raise Exception("Rows affected %s" %
(error.parts[0].values, ))
elif error.parts[0].kind == part_kinds.ERROR:
raise error.parts[0].errors[0]
else:
raise Exception("Invalid reply segment")
def test_unpack_multiple_dummy_parts():
packed = BytesIO(
b"\x7f\x00\x0a\x00\x00\x00\x00\x00\x0a\x00\x00\x00\xc8\xff\x01"
b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
b"\x00\x00\x7f\x00\x0e\x00\x00\x00\x00\x00\x0e\x00\x00\x00\xa8"
b"\xff\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
b"\x00\x00\x00\x00\x7f\x00\x12\x00\x00\x00\x00\x00\x12\x00\x00"
b"\x00\x68\xff\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
)
unpacked = tuple(Part.unpack_from(packed, 3))
assert len(unpacked) == 3
assert isinstance(unpacked[0], DummyPart)
assert unpacked[0].zeros == 10
assert isinstance(unpacked[1], DummyPart)
assert unpacked[1].zeros == 14
assert isinstance(unpacked[2], DummyPart)
assert unpacked[2].zeros == 18
def test_unpack_multiple_dummy_parts(self):
packed = BytesIO(
b"\x7f\x00\x0a\x00\x00\x00\x00\x00\x0a\x00\x00\x00\xc8\xff\x01"
b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
b"\x00\x00\x7f\x00\x0e\x00\x00\x00\x00\x00\x0e\x00\x00\x00\xa8"
b"\xff\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
b"\x00\x00\x00\x00\x7f\x00\x12\x00\x00\x00\x00\x00\x12\x00\x00"
b"\x00\x68\xff\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
)
unpacked = tuple(Part.unpack_from(packed, 3))
assert len(unpacked) == 3
assert isinstance(unpacked[0], DummyPart)
assert unpacked[0].zeros == 10
assert isinstance(unpacked[1], DummyPart)
assert unpacked[1].zeros == 14
assert isinstance(unpacked[2], DummyPart)
assert unpacked[2].zeros == 18
def test_invalid_part_header_raises_exception():
packed = BytesIO(
b"\xbb\xff\xaa\x00\x00\x00\x00\x0a\x00\x00\x00\x00\x00\x00\x00"
)
with pytest.raises(InterfaceError):
tuple(Part.unpack_from(packed, 1))
def test_invalid_part_header_raises_exception(self):
packed = BytesIO(
b"\xbb\xff\xaa\x00\x00\x00\x00\x0a\x00\x00\x00\x00\x00\x00\x00"
)
with pytest.raises(InterfaceError):
tuple(Part.unpack_from(packed, 1))
