Pymodbus 3.4.0, bug in async_execute

[tomas-bozek]

Python: 3.8
Pymodbus: 3.4.0
used on: UDP Client (for our example connection to nowhere, or not existed address)

Bug:
https://github.com/pymodbus-dev/pymodbus/blob/dev/pymodbus/client/base.py#L193
Future is created only ONCE

code tries to use retries, first time it is ok, when more times then wait_for using CANCELLED future!

FIX:
move req = self._build_response(request.transaction_id) to wait_for

async def async_execute(self, request=None):
        """Execute requests asynchronously."""
        request.transaction_id = self.transaction.getNextTID()
        packet = self.framer.buildPacket(request)
        self.transport_send(packet)        
        if self.params.broadcast_enable and not request.slave_id:
            resp = b"Broadcast write sent - no response expected"
        else:
            count = 0
            while count < self.params.retries:
                count += 1
                try:
                    req = self._build_response(request.transaction_id)
                    resp = await asyncio.wait_for(
                        req, timeout=self.comm_params.timeout_connect
                    )
                    break
                except asyncio.exceptions.TimeoutError:
                    pass
            if count == self.params.retries:
                self.close(reconnect=True)
                raise ModbusIOException(
                    f"ERROR: No response received after {self.params.retries} retries"
                )
        return resp

[janiversen]

Pull requests are welcome.

[janiversen]

v3.4.1 will be released this weekend, so that is the deadline for a PR, that is if you want it in the next release cycle.

[tomas-bozek]

v3.4.1 will be released this weekend, so that is the deadline for a PR, that is if you want it in the next release cycle.

I'm on vacation. i shall do it, but after vacation.

[janiversen]

Have a nice vacation.

[tomas-bozek]

Have a nice vacation.

thanks