decimal.InvalidOperation

[ColinRobbins]

I am seeing the followng error in my logs.

I am running HA 2022.8.0b0.
PowerCalc 0.24.3.

I think the error was probably hapening before I upgraded from 2022.7.7, but cannot be certain.
Alas, I can't (easily) roll back to verify to database schema changes in 22.22.8.0b0

The error is ocurring at Startup time, so maybe because the status of a sensor is "Unavailable" or "Unknown" as it has not fully started yet. Thus the conversion to decimal fails.

Logger: homeassistant
Source: custom_components/powercalc/sensors/power.py:447
Integration: Powercalc (documentation, issues)
First occurred: 14:49:00 (1 occurrences)
Last logged: 14:49:00

Error doing job: Task exception was never retrieved
Traceback (most recent call last):
  File "/home/homeassistant/.homeassistant/custom_components/powercalc/sensors/power.py", line 326, in appliance_state_listener
    await self._update_power_sensor(self._source_entity, new_state)
  File "/home/homeassistant/.homeassistant/custom_components/powercalc/sensors/power.py", line 386, in _update_power_sensor
    self._power = await self.calculate_power(state)
  File "/home/homeassistant/.homeassistant/custom_components/powercalc/sensors/power.py", line 447, in calculate_power
    return Decimal(power)
decimal.InvalidOperation: [<class 'decimal.ConversionSyntax'>]

[bramstroker]

I have added extra logging for the next release so we can see which entity is the culprit. And what the value is it is trying to convert to a decimal.

[jfrux]

Getting this as well!

Using template and doing some math so not sure if it's an issue with my template.
My template does render properly in Developer Tools > Template

Example of what I'm using:

{% set power_switch = states('switch.pool_filter_pump') %}
{% set current_speed = states('sensor.pool_filter_pump_speed')|float %}
{% set max_power_draw = 1100 %}
{% if power_switch == "on" %}
{% set current_power_draw = (max_power_draw * (current_speed / 100))|float %}
{% else %}
{% set current_power_draw = 0.0|float %}
{% endif %}
{{ current_power_draw }}

Maybe there is a better way to do it to ensure it's safer but it should at least work for now I'd think.

[jfrux]

I added the |float to everything to ensure it was typed but dunno if that is even necessary.

[bramstroker]

I have found the issue, the problem is with sensors having a template as the value and created with new config flow.
The template is not correctly recognized by powercalc as a template so it is trying to convert the full template string to a decimal (which causes this exception).

Will have some time to write some tests and make the fix tomorrow.

@ColinRobbins did you also use a power sensor with templates?

[ColinRobbins]

I do.

[ColinRobbins]

I may be barking up the wrong tree, but I only see the issue at start up.
In general the template appears to be working.
Is it possible, during HA startup the template is returning a state of "unavailable" or "unknown", which causes the error.

[bramstroker]

I may be barking up the wrong tree, but I only see the issue at start up. In general the template appears to be working. Is it possible, during HA startup the template is returning a state of "unavailable" or "unknown", which causes the error.

hmm I am pretty sure that this bug I reproduced for specifically the config flow created entities will never work if you use a template.
Did you define the template sensor with configuration.yaml or the GUI flow?
Seems you guys have 2 different issues.
@ColinRobbins for the conversion error stack trace you posted I already made some changes yesterday to provide a better error message. When you install 0.24.3 it should give information about the entity and the value which cause the decimal conversion error.

[ColinRobbins]

Hi,
I use configuration.yaml.
I have 0.24.3, and do not see any addiitonal error information:

This error originated from a custom integration.

Logger: homeassistant
Source: custom_components/powercalc/sensors/power.py:447
Integration: Powercalc (documentation, issues)
First occurred: 16:48:35 (1 occurrences)
Last logged: 16:48:35

Error doing job: Task exception was never retrieved
Traceback (most recent call last):
  File "/home/homeassistant/.homeassistant/custom_components/powercalc/sensors/power.py", line 326, in appliance_state_listener
    await self._update_power_sensor(self._source_entity, new_state)
  File "/home/homeassistant/.homeassistant/custom_components/powercalc/sensors/power.py", line 386, in _update_power_sensor
    self._power = await self.calculate_power(state)
  File "/home/homeassistant/.homeassistant/custom_components/powercalc/sensors/power.py", line 447, in calculate_power
    return Decimal(power)
decimal.InvalidOperation: [<class 'decimal.ConversionSyntax'>]

I have several entries with template sensors, and this only throws 1 error.

[bramstroker]

Ah ok configuration.yaml, that's what I expected. So your issue is not similar to @jfrux.
I am sorry, the better error handling was not in v0.24.3 yet. Just released v0.24.4 which contains this.

[ColinRobbins]

No problem - by trial an error, I have tracked it to the following...

- platform: powercalc
  entity_id: sensor.ev_charge_power
  name: EV
  fixed:
    power: "{{states('sensor.ev_power_w')}}"

The sensor sensor.ev_power_w is itself a template sensor, converts kWh to w.

 - name: EV Power W
    unique_id: cjr_46
    state: >
      {% if is_number(states('sensor.ev_charge_power')) %}
        {{ states('sensor.ev_charge_power')|float * 1000 }}
      {% else %}
        0
      {% endif %}
    state_class: measurement
    icon: 'mdi:flash'
    unit_of_measurement: W
    device_class: power

My guess is, that during the startup sequence, sensor.ev_power_w is unavailable, as its one of the last things HA starts.

If I change it to

- platform: powercalc
  entity_id: sensor.electra_charge_power
  name: Electra
  fixed:
    power: >
      {% if is_number(states('sensor.ev_charge_power')) %}
        {{ states('sensor.ev_charge_power')|float * 1000 }}
      {% else %}
        0
      {% endif %}

The error goes away.

[bramstroker]

Ok that's nice. Could you still check what value is in the logs when you use your old simple template? I suspect it is "unknown". When I know this I can have a look into making this a littlte more failsafe so no error will be logged in the error log and you can still use your old template.

[bramstroker]

@ColinRobbins I have found the best solution to your problem.
Currently the initial state of the powercalc power sensor is calculated during setup of powercalc. This could cause issues like you had where one of the template entities is not setup yet.
I have now changed that to calculate the initial state after setup. I am pretty sure this will also solve your problem.
Will be in next release.

@jfrux You issue with the template not being evaluated when using the config flow is also fixed, see #918, this will also be in the upcoming release.

[ColinRobbins]

I've run v0.24.4 and reverted my template.
I now get the error (as anticiapted)

This error originated from a custom integration.

Logger: custom_components.powercalc.sensors.power
Source: custom_components/powercalc/sensors/power.py:326
Integration: Powercalc (documentation, issues)
First occurred: 09:20:18 (1 occurrences)
Last logged: 09:20:18

sensor.ev_charge_power: Could not convert value 'unknown' to decimal

I can now resolve this locally. Thank you.

[bramstroker]

Just released v0.24.5 with proposed fixes mentioned above.
Closing this issue. Let me know if you still experience any issues.