def execute_route(self, meta_data, request_pdu):
""" Execute configured route based on requests meta data and request
PDU.
:param meta_data: A dict with meta data. It must at least contain
key 'unit_id'.
:param request_pdu: A bytearray containing request PDU.
:return: A bytearry containing reponse PDU.
"""
try:
function = create_function_from_request_pdu(request_pdu)
results =\
function.execute(meta_data['unit_id'], self.server.route_map)
try:
# ReadFunction's use results of callbacks to build response
# PDU...
return function.create_response_pdu(results)
except TypeError:
# ...other functions don't.
return function.create_response_pdu()
except ModbusError as e:
function_code = get_function_code_from_request_pdu(request_pdu)
return pack_exception_pdu(function_code, e.error_code)
except Exception as e:
log.exception('Could not handle request: {0}.'.format(e))
function_code = get_function_code_from_request_pdu(request_pdu)
return pack_exception_pdu(function_code,
ServerDeviceFailureError.error_code)
def execute_route(self, meta_data, request_pdu):
""" Execute configured route based on requests meta data and request
PDU.
:param meta_data: A dict with meta data. It must at least contain
key 'unit_id'.
:param request_pdu: A bytearray containing request PDU.
:return: A bytearry containing reponse PDU.
"""
try:
function = create_function_from_request_pdu(request_pdu)
results =\
function.execute(meta_data['unit_id'], self.route_map)
try:
# ReadFunction's use results of callbacks to build response
# PDU...
return function.create_response_pdu(results)
except TypeError:
# ...other functions don't.
return function.create_response_pdu()
except ModbusError as e:
function_code = get_function_code_from_request_pdu(request_pdu)
return pack_exception_pdu(function_code, e.error_code)
except Exception as e:
log.exception('Could not handle request: {0}.'.format(e))
function_code = get_function_code_from_request_pdu(request_pdu)
return pack_exception_pdu(function_code,
ServerDeviceFailureError.error_code)
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.
"""
log.debug('Lenght of received ADU is {0}.'.format(len(request_adu)))
log.info('<-- {0} - {1}.'.format(self.client_address[0],
hexlify(request_adu)))
try:
transaction_id, protocol_id, _, unit_id = \
unpack_mbap(request_adu[:7])
function = function_factory(request_adu[7:])
results = function.execute(unit_id, self.server.route_map)
try:
# ReadFunction's use results of callbacks to build response
# PDU...
response_pdu = function.create_response_pdu(results)
except TypeError:
# ...other functions don't.
response_pdu = function.create_response_pdu()
except ModbusError as e:
function_code = get_function_code_from_request_pdu(request_adu[7:])
response_pdu = pack_exception_pdu(function_code, e.error_code)
except Exception as e:
log.exception('Could not handle request: {0}.'.format(e))
function_code = get_function_code_from_request_pdu(request_adu[7:])
response_pdu = \
pack_exception_pdu(function_code,
ServerDeviceFailureError.error_code)
response_mbap = pack_mbap(transaction_id, protocol_id,
len(response_pdu) + 1, unit_id)
log.debug('Response MBAP {0}'.format(response_mbap))
log.debug('Response PDU {0}'.format(response_pdu))
response_adu = response_mbap + response_pdu
return response_adu
def test_pack_exception_pdu():
""" Exception PDU should correct encoding of error code and function code.
"""
assert pack_exception_pdu(1, 1) == b'\x81\x01'
def test_pack_exception_pdu():
""" Exception PDU should correct encoding of error code and function code.
"""
assert pack_exception_pdu(1, 1) == b'\x81\x01'
