def confirmation(self, pdu):
"""This is a request from a client."""
if _debug: ModbusServer._debug("confirmation %r", pdu)
# generic decoding
mpdu = MPDU()
mpdu.decode(pdu)
if _debug: ModbusServer._debug(" - mpdu: %r", mpdu)
# we don't know anything but MODBUS
if (mpdu.mpduProtocolID != 0):
return
# clients shouldn't be sending exceptions
if (mpdu.mpduFunctionCode >= 128):
return
# map the function code
klass = request_types.get(mpdu.mpduFunctionCode, None)
if not klass:
# create an error for now
resp = ExceptionResponse(
mpdu.mpduFunctionCode,
ExceptionResponse.ILLEGAL_FUNCTION,
)
# match the transaction information
resp.pduDestination = mpdu.pduSource
resp.mpduTransactionID = mpdu.mpduTransactionID
if _debug: ModbusServer._debug(" - resp: %r", resp)
# return the response to the device
self.request(resp)
req = klass()
req.decode(mpdu)
if _debug: ModbusServer._debug(" - req: %r", req)
# pass it along to the application
self.response(req)
