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# Groovy Scripting
This add-on provides support for Groovy (opens new window) 4.0.11 that can be used as a scripting language within automation rules and which eliminates the need to manually install Groovy.
# Creating Groovy Scripts
When this add-on is installed, you can select Groovy as a scripting language when creating a script action within the rule editor of the UI.
Alternatively, you can create scripts in the automation/jsr223
configuration directory.
If you create an empty file called test.groovy
, you will see a log line with information similar to:
... [INFO ] [.a.m.s.r.i.l.ScriptFileWatcher:150 ] - Loading script 'test.groovy'
To enable debug logging, use the console logging commands to enable debug logging for the automation functionality:
log:set DEBUG org.openhab.core.automation
For more information on the available APIs in scripts see the JSR223 Scripting documentation.
# Code reuse
One can place *.groovy files with Groovy classes under automation/groovy
configuration directory.
Those classes can be imported in JSR-223 scripts or the UI rules action with the usual Groovy import
statement.
To apply shared code changes, one has to restart the openHAB Core :: Bundles :: Automation
bundle on the Console or an openHAB instance altogether.
# Script Examples
Groovy scripts provide access to almost all the functionality in an openHAB runtime environment.
As a simple example, the following script logs "Hello, World!".
Note that System.out.println
will usually not work since the output has no terminal to display the text.
The openHAB server uses the SLF4J (opens new window) library for logging.
import org.slf4j.LoggerFactory
LoggerFactory.getLogger("org.openhab.core.automation.examples").info("Hello, World!")
Depending on the openHAB logging configuration, you may need to prefix logger names with org.openhab.core.automation
for them to show up in the log file (or you modify the logging configuration).
The script uses the LoggerFactory (opens new window) to obtain a named logger and then logs a message like:
... [INFO ] [.openhab.core.automation.examples:-2 ] - Hello, World!