Instrument settings

[YagoDel]

My problem: I kinda want the Andor to go back to the settings I last left it in, not change when self.initialize gets called

More general problem: have instruments save/load a set of settings. Could be handled similar to metadata_property_names, maybe even the same actually

[rwb27]

Related idea I never managed to implement: have a context manager that allows you to temporarily change a property. So instead of:

prev_exposure = camera.exposure_time
camera.exposure_time = 10
image = camera.take_snapshot()
camera.exposure_time = prev_exposure

you could do:

with camera.temporarily_set(exposure_time=10):
    image = camera.take_snapshot()

That is not only way neater (especially if you're changing more than one setting), it's also much more robust to errors, etc.

Consistently managing settings is tricky - so I will be curious to see what you come up with here. I've quite enjoyed our settings mechanism in LabThings because a side-effect of the way we've done it is that it becomes trivially easy to download all the current settings as JSON, and restore the state of the instrument by sending said JSON back to the server.

[YagoDel]

Related to that context manager, I had a quick go adding this as an Instrument method and tested it with the Andor to do what you described:

@contextmanager

def temporarily_set(self, **kwargs):
    
    try:
        
        original_settings = dict()

        for key, value in kwargs.items():

            original_settings[key] = getattr(self, key)

            setattr(self, key, value)

        yield original_settings

    finally:

        for key, value in original_settings.items():

            setattr(self, key, value)

I'm wondering if I'm being stupid.

Thanks for pointing out LabThings! I was indeed thinking something with that kind of JSON functionality (although I was thinking YAML), but indeed finding something consistent is going to be interesting...

[YagoDel]

Made a first pass at this (in branch issue124). It works for what I wanted to do with the Andor