def process(self, request_adu):
""" Process request ADU and return response.
:param request_adu: A bytearray containing the ADU request.
:return: A bytearray containing the response of the ADU request.
"""
validate_crc(request_adu)
return super(RTUServer, self).process(request_adu)
def process(self, request_adu):
""" Process request ADU and return response.
:param request_adu: A bytearray containing the ADU request.
:return: A bytearray containing the response of the ADU request.
"""
validate_crc(request_adu)
return super(RTUServer, self).process(request_adu)
def get_frame(adu):
frame = adu[:2]
i = 2
while 1:
try:
validate_crc(frame)
break
except (CRCError, struct.error) as e:
frame += adu[i:i + 1]
i += 1
return frame
def test_request_returning_server_device_failure_error(rtu_server, function):
""" Validate response PDU of request returning excepetion response with
error code 4.
"""
adu = function()
function_code = struct.unpack('>B', adu[1:2])[0]
rtu_server.serial_port.write(adu)
rtu_server.serve_once()
resp = rtu_server.serial_port.read(rtu_server.serial_port.in_waiting)
validate_crc(resp)
assert struct.unpack('>BB', resp[1:-2]) == (0x80 + function_code, 4)
def test_request_returning_invalid_data_value_error(rtu_server, function_code,
quantity):
""" Validate response PDU of request returning excepetion response with
error code 3.
"""
starting_address = 0
slave_id = 1
adu = add_crc(struct.pack('>BBHH', slave_id, function_code,
starting_address, quantity))
rtu_server.serial_port.write(adu)
rtu_server.serve_once()
resp = rtu_server.serial_port.read(rtu_server.serial_port.in_waiting)
validate_crc(resp)
assert struct.unpack('>BB', resp[1:-2]) == (0x80 + function_code, 3)
def parse_response_adu(resp_adu, req_adu=None):
""" Parse response ADU and return response data. Some functions require
request ADU to fully understand request ADU.
:param resp_adu: Resonse ADU.
:param req_adu: Request ADU, default None.
:return: Response data.
"""
resp_pdu = resp_adu[1:-2]
validate_crc(resp_adu)
req_pdu = None
if req_adu is not None:
req_pdu = req_adu[1:-2]
function = create_function_from_response_pdu(resp_pdu, req_pdu)
return function.data
def parse_response_adu(resp_adu, req_adu=None):
""" Parse response ADU and return response data. Some functions require
request ADU to fully understand request ADU.
:param resp_adu: Resonse ADU.
:param req_adu: Request ADU, default None.
:return: Response data.
"""
resp_pdu = resp_adu[1:-2]
validate_crc(resp_adu)
req_pdu = None
if req_adu is not None:
req_pdu = req_adu[1:-2]
function = create_function_from_response_pdu(resp_pdu, req_pdu)
return function.data
def parse_response_adu(resp_adu, req_adu=None):
""" Parse response ADU and return response data. Some functions require
request ADU to fully understand request ADU.
:param resp_adu: Resonse ADU.
:param req_adu: Request ADU, default None.
:return: Response data.
"""
aes = AES.new(key, AES.MODE_CBC, IV)
resp_pdu = aes.decrypt(resp_adu[1:-2])
validate_crc(resp_adu)
req_pdu = None
if req_adu is not None:
req_pdu = req_adu[1:-2]
aes = AES.new(key, AES.MODE_CBC, IV)
req_pdu = aes.decrypt(req_pdu)
function = create_function_from_response_pdu(resp_pdu, req_pdu)
return function.data
def test_validate_invalid_crc():
"""" Method should raise assertion error. """
with pytest.raises(CRCError):
validate_crc(b'\x01\x02\x07')
def test_validate_valid_crc():
"""" Method should not raise assertion error. """
validate_crc(b'\x00\x01\x02\xf1\x91')
