Short question on pytango Device.init_device() and Device.delete_device()

Development Python
1

Hello there,
after some time of working with the basic functionalities of pytango and its high level server API I found myself frequently using init_device() to create instance variables and got curious whether this is the right way to handle things. Whenever I create one my IDE complains, that it should not be declared outside of init() (which to my understanding should not/ does not need to be accesed by me at all, right?) which makes me wonder whether these are now any different from instance variables created in init() (as done in regular python usage).

A little recent example of mine would be a server in need of a background thread. Currently my thread is created and started in init_device() and a stop event is triggered in delete_device(). Is this the “correct” way to use these two methods or am i overseeing some unforeseen consequences here?

2

Hi larpsid,

I would say your logic is correct.

You can initialize the variables to None in init to prevent IDE warnings or tag the init_device with #noqa so the IDE does not complain (I prefer the second):


class MyDevice(Device):

    def init_device(self):
        super().init_device()
        self.task = threading.Thread(target=...)  # noqa

    def delete_device(self):
        self.stop_task.set()
        self.task.join()
        self.task = None