def decode(cls, data):
"Decodes the PDU from the given data bytes"
new_pdu = cls()
idx = 0
for member in cls._orderedKeys:
if not member.startswith("__") and not callable(getattr(cls, member)):
M = getattr(cls, member)
if Integer == type(M): # in [Integer, CString, String, TLV]
s = data[idx:idx+M.length]
idx = idx + M.length
setattr(new_pdu, member, Integer.decode(s))
elif CString == type(M):
# Need to find the next NULL character which is the string's end
try:
nidx = data.index(b'\x00', idx)
s = data[idx:nidx+1]
idx = nidx + 1
setattr(new_pdu, member, CString.decode(s))
except:
raise RuntimeError("Cannot find end for CString type")
elif String == type(M):
# TODO: Since string fields can either be fixed length or have a corresponding
# length field specifying their length, decoding this requires some info to
# be passed from within the PDU class.
pass
elif TLV == type(M):
pass
return new_pdu
def test_02_integer_decode():
"Test to check 1, 2 and 4 byte integer decoding"
assert 5 == Integer.decode(b'\x05').value
assert 41746 == Integer.decode(b'\xa3\x12').value
assert 31022623 == Integer.decode(b'\x01\xd9^\x1f').value
