Custom Response Class registration lost due to ModbusFramer being inialized multiple times

[wlcrs]

Versions

• Python: 3.10.2
• OS: Ubuntu 20.04
• Pymodbus: 3.0.0
• Modbus Hardware (if used):

Pymodbus Specific

• Client: tcp async

Description

I'm trying to upgrade to 3.0.0, but run into trouble with registering my custom response class.

I do this like this:

client = AsyncModbusTcpClient(host,   port,     framer=ModbusSocketFramer)
client.register(PrivateHuaweiModbusResponse)   

This correctly adds the response to the client.framer.decoder.__lookup table

However, upon callling client.connect(), I see that in AsyncModbusTcpClient._create_protocol, it does not pass client.framer to the ModbusClientProtocol, but instead the self.params.framer:

       protocol = ModbusClientProtocol(framer=self.params.framer, **self.params.kwargs)

In the protocol-object, the framer is initialized again, without the custom response class this time.

I'm very confused about how both AsyncModbusTcpClient and ModbusClientProtocol have ModbusBaseClient as a parent class. Would it not be more appropriate to remove ModbusBaseClient as a parent class from ModbusClientProtocol and pass the client-object creating the ModbusClientProtocol to it instead?

[janiversen]

We are moving in the direction of having the code common between sync and async thus the need for a common base class.

Seems however you found a real bug, I will add a test case and solve it.

[janiversen]

3.0.1 is due beginning November and will include the fix. It would be nice if you could test it before then.

HomeAssistant modbus integration is also due to be bumped to use the new library.

[wlcrs]

I was able to successfully complete the migration of my huawei-solar library to pyModbus 3.x. Thank you for the code cleanup. The API looks much nicer now. 👍

I'll release a new version of my HA integration when 3.0.1 is released.