How to use the logger

You should always use the self.logger object of SKADevice within methods. This instance of the logger is the only one that knows the Tango device name. You can also use the PyTango logging decorators like tango.DebugIt, since the monkey patching in SKADevice redirects them to that same logger.

class MyDevice(SKADevice):
    def my_method(self):
        someone = "you"
        self.logger.info("I have a message for %s", someone)

    @tango.DebugIt(show_args=True, show_ret=True)
    def my_handler(self):
        # great, entry and exit of this method is automatically logged
        # at debug level!
        pass

Yes, you could use f-strings. f"I have a message for {someone}". The only benefit of the %s type formatting is that the full string does not need to be created unless the log message will be emitted. This could provide a small performance gain, depending on what is being logged, and how often.

Changing the logging level

The loggingLevel attribute allows adjusting the severity of logs being emitted. This attribute is an enumerated type. The default is currently INFO level, but it can be overridden by setting the LoggingLevelDefault property in the Tango database.

Example:

proxy = tango.DeviceProxy('my/test/device')

# change to debug level using an enum
proxy.loggingLevel = ska_control_model.LoggingLevel.DEBUG

# change to info level using a string
proxy.loggingLevel = "INFO"

Do not use tango.DeviceProxy.set_logging_level(). That method only applies to the Tango Logging Service (TLS) - see Additional logging targets. However, note that when the loggingLevel attribute is set, we internally update the TLS logging level as well.