As of r902947, Sling Scripting allows bundles to contribute objects to the variables available to scripts by exposing OSGi services.
This can be done by implementing either java.util.Map or org.apache.sling.scripting.api.BindingsValuesProvider. Implement org.apache.sling.scripting.api.BindingsValuesProvider if you need access to the current script variables.
In either case, implementations are able to add one or more name/value pairs to the javax.script.Bindings object, but they cannot overwrite or remove any of the default scripting variables (defined here: Scripting Variables). These custom bindings can be configured to apply to any scripting language or a specific scripting language.
An example of the binding of a custom object using java.util.Map can be found in the extensions.groovy bundle (source):
import org.apache.sling.commons.json.groovy.JSONGroovyBuilder;
/**
* BindingsValuesProvider which binds an instance of JSONGroovyBuilder.
*
* @scr.component immediate="true" metatype="no"
* @scr.service
*
* @scr.property name="service.description" value="JSONGroovyBuilder BindingsValuesProvider"
* @scr.property name="service.vendor" value="The Apache Software Foundation"
*
* @scr.property name="javax.script.name" value="groovy"
*/
public class JSONGroovyBuilderBindingsValuesProvider extends HashMap<String,Object> {
public JSONGroovyBuilderBindingsValuesProvider() {
super();
put("jsonBuilder", new JSONGroovyBuilder());
}
}
In this example, the jsonBuilder key is bound to an instance of JSONGroovyBuilder only for Groovy scripts.
An example of the binding of a custom object using org.apache.sling.scripting.api.BindingsValuesProvider can be found in the jcr.resource bundle (source):
import javax.jcr.Node;
import javax.script.Bindings;
import org.apache.sling.api.resource.Resource;
import org.apache.sling.scripting.api.BindingsValuesProvider;
/**
* BindingsValuesProvider for currentNode object.
*
* @scr.component immediate="true" metatype="no"
* @scr.service
*
* @scr.property name="service.description" value="CurrentNode BindingsValuesProvider"
* @scr.property name="service.vendor" value="The Apache Software Foundation"
*
* @scr.property name="javax.script.name" value="any"
*/
public class CurrentNodeBindingsValuesProvider implements BindingsValuesProvider {
/**
* {@inheritDoc}
*/
public void addBindings(Bindings bindings) {
Resource resource = (Resource) bindings.get("resource");
Node node = resource.adaptTo(Node.class);
if (node != null) {
bindings.put("currentNode", node);
}
}
}