Using a rain sensor to control irrigation

Third party integrations Node-RED
1

Hardware:
RB-SRAIN01 Solar Rain Sensor
QT06_2 Water irrigation valve

Problem description:
I want to sample data points for rain intensity every 5 minutes during the day.
If there is more than 10 datapoints with heavy rain since last irrigation, then I do not want to turn on the irrigation valve at the evening.
If there is more than 20 datapoints with moderate rain since last irrigation, then I do not want to turn on the irrigation valve at the evening.
If there is more than 30 datapoints with rain at all since last irrigation, then I do not want to turn on the irrigation valve at the evening.
Otherwise, turn on irrigation for half an hour at 18:00 in the evening.

I have defined the different rain levels through a templated helper sensor:

template:
  - sensor:
      - name: "Rain Rate"
        state: >
          {% set intensity = states('sensor.tuya_rain_sensor_rb_srain01_rain_intensity') | int %}
          {% if intensity < 10 %}
            No Rain
          {% elif intensity <= 2000 %}
            Light Rain
          {% elif intensity <= 2600 %}
            Moderate Rain
          {% else %}
            Heavy Rain
          {% endif %}

The part with choosing when to start or not to start irrigation I have pretty much under control.
But I struggle with how to store counters which increase the value by one when there is some type of rain, and how to reset it at 18:30.
I reckon it will be something like this:
if “Heavy Rain” then ++Heavy_Rain_Counter;
if “Moderate Rain” then ++Moderate_Rain_Counter;
if (“Heavy Rain” or “Moderate Rain” or “Light Rain”) then ++Rain_Counter;

Is the solution a timed inject node which fetch “Rain Rate”, and goes to a switch node, which stores it to a global value?
(How do I save the global value so that it does not go away in case of a reboot, or a Node Red restart?)

Any hints, tips, tricks, pointers will be much appreciated.

2

You would need to enable context store to file.

https://nodered.org/docs/user-guide/context#saving-context-data-to-the-file-system

Use the inject to trigger every 5 seconds.

It would be better to use counter helpers from home assistant. This will store the values in history and it will survive restarts. You will also have an entity that can be displayed on the dash.

Use the action counter.increment to increase the counter. Then use an inject set to fire @ 18:30 and use the action counter.reset to return it to it’s initial value.

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