Skip to main content Link Search Menu Expand Document (external link)
OpenHAB JRuby Script Library

Creating Rules in Main UI

Rules can be created in the UI as well as in rules files, but some things are a bit different. First of all, only the execution blocks need to be created in the script. All triggers and conditions are created directly in the UI instead.

To create a rule:

  1. Go to the Rules section in the UI and add a new rule.
  2. Input a name for your rule, and configure the Triggers through the UI.
  3. When adding an Action, select Run script, and then Ruby. A script editor will open where you can write your code.
  4. When you are done, save the script and go back to complete the configuration.

UI Rules vs File-based Rules

The following features of this library are only usable within file-based rules:

  • Triggers: UI-based rules provide equivalent triggers through the UI.
  • Guards: UI-based rules use Conditions in the UI instead. Alternatively it can be implemented inside the rule code.
  • Execution Blocks: The UI-based rules will execute your JRuby script as if it’s inside a run execution block. A special event variable is available within your code to provide it with additional information regarding the event. For more details see the run execution block.
  • delay: There is no direct equivalent in the UI. It can be achieved using timers like in the example below.
  • otherwise: There is no direct equivalent in the UI. However, it can be implemented within the rule using an if-else block.

Loading the Scripting Library

To make all the features offered by this library available to your rule, the JRuby scripting addon needs to be configured to install the openhab-scripting gem and require the openhab script. This will enable all the special methods for Items, Things, Actions, Logging etc. that are documented here, and the event properties documented for the Run execution block.

Examples

Reset the switch that triggered the rule after 5 seconds

Trigger defined as:

  • When: a member of an item group receives a command
  • Group: Reset_5Seconds
  • Command: ON
logger.info("#{event.item.id} Triggered the rule")
after 5.seconds do
  event.item << OFF
end

Update a DateTime Item with the current time when a motion sensor is triggered

Given the following group and items:

Group MotionSensors
Switch Sensor1 (MotionSensors)
Switch Sensor2 (MotionSensors)

DateTime Sensor1_LastMotion
DateTime Sensor2_LastMotion

Trigger defined as:

  • When: the state of a member of an item group is updated
  • Group: MotionSensors
  • State: ON
logger.info("#{event.item.id} Triggered")
items["#{event.item_name}_LastMotion"].update Time.now