Multiple SerialPorts within single Twisted reactor

Question

I am trying to setup a program with twisted to emulate a serial devices that sends/receives AT commands. Different devices open a different amount of serial ports and use these ports for different things.

I would like my application to be able to open as many SerialPorts as needed and to know what serial Device is writing to dataReceived. I did not want to run each port on a different reactor or thread.

Is there anyway to do this ?

class VirtualDeviceBase(LineReceiver): 
    def __init__(self, reactor, serial_address):
    [...]

    def open_port(self):
        self.serial_device = SerialPort(self, serial_address, reactor)
        self.serial_device2 = SerialPort(? , serial_address, reactor)

    def dataReceived(self,data):
        [...]

I have tried this:

class VirtualDeviceBase(LineReceiver): 

    class Protocol(LineReceiver):
        def __init__(self,reactor,address):
            [...]

    def open_port(self):
        new_protocol = self.Protocol()
        self.serial_device = SerialPort(self, serial_address, reactor)
        self.serial_device2 = SerialPort(new_protocol , serial_address, reactor)

and it does not throw any errors but than neither of them call dataRecevied any more.

Answer 1

Just instantiate two SerialPort s. Give them whatever protocols you like. They can share a reactor. A single reactor can handle many different event sources.

from twisted.internet.protocol import Protocol
from twisted.internet.serial import SerialPort
from twisted.internet.task import react

class Echo(Protocol):
    def dataReceived(self, data):
        print("Received: {}".format(data))

def main(reactor):
    SerialPort(Echo(), "com0", reactor)
    SerialPort(Echo(), "com1", reactor)

react(main, [])