Measurement state_class and statistics are not working

Development
1

I can’t for the life of me work out how to provide the state_class and last_reset properties to Home Assistant such that users can access statistics for the values.

I’ve even tried overly verbose logging (original source):

    @property
    def state_class(self):
        """Return the state class if relevent"""
        measurement = getattr(self.__statistic, "measurement", False)
        if measurement:
            _LOGGER.debug("Is measurement class")
            return "measurement"
        else:
            _LOGGER.error("Is not measurement class")
            return None

And I’m never seeing those properties being accessed by Home Assistant.

Of course - this means that there are no statistics available when trying to access them in lovelace:

Screen Shot 2021-08-15 at 6.33.27 pm
Screen Shot 2021-08-15 at 6.33.27 pm1004×232 7.53 KB

2

It seems setting a state_class of measurement does not yet work.

I assume statistics has been pre-documented before being implemented?

Does anybody know if statistics is still coming, or this is a bug?

Screen Shot 2021-08-21 at 11.42.24 am
Screen Shot 2021-08-21 at 11.42.24 am1194×288 21.2 KB
Screen Shot 2021-08-21 at 11.42.40 am
Screen Shot 2021-08-21 at 11.42.40 am788×960 52.1 KB

3

Does your sensor extend the Entity class or the SensorEntity class?

4

Thank-you @anotherjulien - it’s SensorEntity link

Is there any documentation I can refer to? Is the RestoreEntity the issue?

class NSWCovidEntry(RestoreEntity, SensorEntity):
    """Represent a NSW Covid Statistic."""

    def __init__(
        self,
        statistic,
    ):
        """Set up NSW Covid entity."""
        self.__statistic = statistic
5

It might make sense that not using a built-in device_class along with its default unit_of_measurement could be the problem, don’t you think?
The only default device_class you seem to use is timestamp and I’m not even sure how it would make sense to extract statistics from this type of measurement. :slightly_frowning_face:

Just to be on the safe side, I’d try to set last_reset to dt_util.utc_from_timestamp(0) (with from homeassistant.util import dt as dt_util) instead of None by default, but I’m not sure it makes sense for measurements that are not continually accumulating…

6

I’m not sure I follow? The default is timestamp - that doesn’t mean that everything (or anything) is the default. (see image in previous post) - the unit of measurement for most of the sensors is “cases” or “doses”

Additionally - I’d like to keep last_reset as the actual last reset value - rather than epoch

7

What I mean is that except for ISO8601, you only seem to use custom unit_of_measurement

    def unit_of_measurement(self):
        """Return the unit of measurement"""
        if (
            self.__statistic.typeName
            and self.__statistic.typeName is not None
            and self.__statistic.typeName in TIMESTAMP_TYPES
        ):
            return "ISO8601"

        if self.__statistic.unit and self.__statistic.unit == "case":
            return "cases"

        if self.__statistic.unit and self.__statistic.unit == "death":
            return "deaths"

        if self.__statistic.unit and self.__statistic.unit == "dose":
            return "doses"

        if self.__statistic.unit and self.__statistic.unit == "test":
            return "tests"

        return self.__statistic.unit

Same with device_class for which you seem to have timestamp or None

    def device_class(self):
        """Return the device class if relevent"""
        if (
            self.__statistic.typeName
            and self.__statistic.typeName is not None
            and self.__statistic.typeName in TIMESTAMP_TYPES
        ):
            return "timestamp"
        return None

My concern is that HA might only be able to generate statistics for known device_class with suitable unit_of_measurement.

As far as the last_reset, my suggestion is only to replace None in the following; not to return dt_util.utc_from_timestamp(0) systematically.

    def last_reset(self):
        """Return the state class if relevent"""
        resetting = getattr(self.__statistic, "resetting", False)
        if not resetting:
            return None
        return self.__statistic.published
1 Like
8

Indeed. This should change in the next version

1 Like