def test_to_bytes(self):
vals = {'buf': self.MAGIC}
with self.subTest('with no length constraints'):
field = codec.Buf('buf') # default: len=0
self.assertEqual(field.to_bytes(vals), self.MAGIC)
with self.subTest('with length constraints'):
field = codec.Buf('buf', len=len(self.MAGIC))
self.assertEqual(field.to_bytes(vals), self.MAGIC)
with self.subTest('EncodeError due to length mismatch'):
field = codec.Buf('buf', len=4)
with self.assertRaises(codec.EncodeError):
field.to_bytes(vals)
class PDUv0Rx(codec.Envelope):
STRUCT = (
Header(ver=0),
codec.Uint32BE('fn'),
codec.Uint('rssi', mult=-1),
codec.Int16BE('toa256'),
codec.Buf('soft-bits'),
codec.Buf('pad'), # Optional
)
def __init__(self, *args, **kw):
codec.Envelope.__init__(self, *args, **kw)
# Field 'soft-bits' is either 148 (GMSK) or 444 (8-PSK) octets long
self.STRUCT[-2].get_len = lambda _, data: 444 if len(data
) > 148 else 148
class PDUv0Tx(codec.Envelope):
STRUCT = (
Header(ver=0),
codec.Uint32BE('fn'),
codec.Uint('pwr'),
codec.Buf('hard-bits'),
)
def test_from_bytes(self):
vals = {}
with self.subTest('with no length constraints'):
field = codec.Buf('buf') # default: len=0
offset = field.from_bytes(vals, self.MAGIC)
self.assertEqual(vals['buf'], self.MAGIC)
self.assertEqual(offset, len(self.MAGIC))
with self.subTest('with length constraints'):
field = codec.Buf('buf', len=2)
offset = field.from_bytes(vals, self.MAGIC)
self.assertEqual(vals['buf'], self.MAGIC[:2])
self.assertEqual(offset, len(self.MAGIC[:2]))
with self.subTest('DecodeError due to not enough bytes'):
field = codec.Buf('buf', len=64)
with self.assertRaises(codec.DecodeError):
field.from_bytes(vals, self.MAGIC)
class TLV(codec.Envelope):
STRUCT = (
codec.Uint('T'),
codec.Uint('L'),
codec.Buf('V'),
)
def __init__(self, *args, **kw) -> None:
codec.Envelope.__init__(self, *args, **kw)
self.STRUCT[-2].get_val = lambda v: len(v['V'])
self.STRUCT[-1].get_len = lambda v, _: v['L']
class TestPDU(codec.Envelope):
STRUCT = (
codec.BitFieldSet(len=2, set=(
codec.BitField('ver', bl=4),
codec.BitField('flag', bl=1),
)),
codec.Uint16BE('len'),
codec.Buf('data'),
codec.Buf('tail', len=2),
)
def __init__(self, *args, **kw):
codec.Envelope.__init__(self, *args, **kw)
self.STRUCT[-3].get_val = lambda v: len(v['data'])
self.STRUCT[-2].get_len = lambda v, _: v['len']
self.STRUCT[-1].get_pres = lambda v: bool(v['flag'])
def check(self, vals: dict) -> None:
if not vals['ver'] in (0, 1, 2):
raise ValueError('Unknown version %d' % vals['ver'])