I have a question. I am running a python project with multiple files with multiple classes. Let's say in file A, I am running a process in a try-exception. In this try-exception a function is called from a different file B/class.

The function in file B is quite complicated as there a a couple while/ and try-exceptions statements. However, within the most inside function, I am putting a counter and if this counter reaches a certain amount, I want it to raise an error that takes me back to the try-exception / to a specific point in file A. The problem that I now have is that the error that I am raising doesn't abort the function in file/class B so it would take me to file/class A, but it takes me to the with.media.getSynchronous statement that is outside of the try-exception, see code below:

        with self.media.getSynchronous():
        if not reply.isStreaming():
            self.writeTrace("TX: " + self.now() + "\t" + GXByteBuffer.hex(data), TraceLevel.VERBOSE)
            self.media.send(data)
        pos = 0
        try:
            while not self.client.getData(rd, reply, notify):
                if notify.data.size != 0:
                    if not notify.isMoreData():
                        t = GXDLMSTranslator()
                        xml = t.dataToXml(notify.data)
                        print(xml)
                        notify.clear()
                    continue
                if not p.eop:
                    p.count = self.client.getFrameSize(rd)
                while not self.media.receive(p):
                    pos += 1
                    if pos == 4:
                        raise TimeoutException("Failed to receive reply from the device in given time.")
                    if pos == 1:
                        self.counter+= 1
                        if self.counter>= 2:
                            logging.warning(f"Worker {self.worker_id} | counteris {self.counter}")
                            raise STOP(f"Data send failed, limit reached ({self.counter})")
                    logging.info(f"Worker {self.worker_id} | Meter ({self.meternummer}) - Data send failed. Try to resend " + str(pos) + f"/3, times: {self.counter}")
                    self.media.send(data, None)
                rd.set(p.reply)
                p.reply = None
          # except STOP as a:  # i have tried to put an specific exception like below here, in order to stop, but still the function continues
        #     break
        except Exception as e:
            self.writeTrace("RX: " + self.now() + "\t" + str(rd), TraceLevel.ERROR)
            raise e
        self.writeTrace("RX: " + self.now() + "\t" + str(rd), TraceLevel.VERBOSE)
        if reply.error != 0:
            raise GXDLMSException(reply.error)

My error definition

class STOP(Exception):
pass

Is there a way that I call an exception or return so that I go back to file A, because now the script gets stuck in file B

I have a question. I am running a python project with multiple files with multiple classes. Let's say in file A, I am running a process in a try-exception. In this try-exception a function is called from a different file B/class.

The function in file B is quite complicated as there a a couple while/ and try-exceptions statements. However, within the most inside function, I am putting a counter and if this counter reaches a certain amount, I want it to raise an error that takes me back to the try-exception / to a specific point in file A. The problem that I now have is that the error that I am raising doesn't abort the function in file/class B so it would take me to file/class A, but it takes me to the with.media.getSynchronous statement that is outside of the try-exception, see code below:

        with self.media.getSynchronous():
        if not reply.isStreaming():
            self.writeTrace("TX: " + self.now() + "\t" + GXByteBuffer.hex(data), TraceLevel.VERBOSE)
            self.media.send(data)
        pos = 0
        try:
            while not self.client.getData(rd, reply, notify):
                if notify.data.size != 0:
                    if not notify.isMoreData():
                        t = GXDLMSTranslator()
                        xml = t.dataToXml(notify.data)
                        print(xml)
                        notify.clear()
                    continue
                if not p.eop:
                    p.count = self.client.getFrameSize(rd)
                while not self.media.receive(p):
                    pos += 1
                    if pos == 4:
                        raise TimeoutException("Failed to receive reply from the device in given time.")
                    if pos == 1:
                        self.counter+= 1
                        if self.counter>= 2:
                            logging.warning(f"Worker {self.worker_id} | counteris {self.counter}")
                            raise STOP(f"Data send failed, limit reached ({self.counter})")
                    logging.info(f"Worker {self.worker_id} | Meter ({self.meternummer}) - Data send failed. Try to resend " + str(pos) + f"/3, times: {self.counter}")
                    self.media.send(data, None)
                rd.set(p.reply)
                p.reply = None
          # except STOP as a:  # i have tried to put an specific exception like below here, in order to stop, but still the function continues
        #     break
        except Exception as e:
            self.writeTrace("RX: " + self.now() + "\t" + str(rd), TraceLevel.ERROR)
            raise e
        self.writeTrace("RX: " + self.now() + "\t" + str(rd), TraceLevel.VERBOSE)
        if reply.error != 0:
            raise GXDLMSException(reply.error)

My error definition

class STOP(Exception):
pass

Is there a way that I call an exception or return so that I go back to file A, because now the script gets stuck in file B

• python

1 Answer 1

Generalising your case, to something easier, this is how you should handle your custom error.

# python

# Your custom error declaration
class StopError(Exception):
    pass  

def functionB():
    # Let exceptions propagate naturally without redundant try/except blocks
    # Your other logic goes here
    for i in range(3):
        if i >= 2:
            # Raising error in loops breaks them
            raise StopError("Data limit reached")

def functionA():
    print("Do something")
    try:
        functionB()
    except StopError as se:
        # Handle the specific custom exception
        print("Handled StopError:", se)
    except Exception as e:
        # Catch any other exceptions
        print("An unexpected error occurred:", e)
        
    print("Continue doing something")

functionA()

But if you expect this error to be raised every time the loop iterates, I would question why you need to raise it at all, instead of trying to add more try/excepts.

Alternatively, you can read up on decorators in Python, and specifically about error interceptors, if you want your error handling logic neatly in one place.