Configure irrigation system over mqtt

Add-ons Bindings
,
1

I´ve an irrigation system that can be configured and controlled over mqtt, just publising messages.

For example:
// (1) to enable an irrigation line
irrigation/greenhouse/pots/enable “1”
// (2) to start irrigation manually
irrigation/greenhouse/state “1”
// (3) to set the irrigation time of specific line
irrigation/greenhouse/pots/time “15”
// (4) to set irrigation schedule
irrigation/greenhouse/schedule “0 0 4 * * ?”

How can I integrate this to OH. I already have some lights working with mqtt just fine but in this case my specific doubt is when I need to send data to it, not just changing its state (examples 3 & 4)

Any help will be appreciated.

2

You can install and use the mqtt action:

publish(String brokerName, String topic, String message)

Use this in a rules

publish(String brokerName, String topic, String message)

For example:

publish("yourbroker", "irrigation/greenhouse/schedule", "0 0 4 * * ? *")
3

Thanks for your response. What you suggest is good, but the value would be harcoded within the rule. Is there any way to take that value from any source in a way that could be updated from any of the UI’s??

4

Yes of course there is
Depends what your cron string needs basicaly
Your current string triggers at 4am everyday
So you could have the value 4 in a Dimmer item in the UI and use a slider to select the number
Then your rule will be like:

rule "schedule changed"
when
    Item Irrigation_Schedule changed
then
    val hour = String::format("%d", (Irrigation_Schedule.state as DecimalType).floatValue())
    val cronString = "0 0 " + hour + " * * ? *"
    publish("yourbroker", "irrigation/greenhouse/schedule", cronString)
end
5

I’ll try it! Tranks for your help.