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The Dynamic Server Configuration Service (DSCS) is built around the Basic Configuration Service. The DSCS provides the environment to change specific Sakai properties during run-time using JMX.

Usage

  • Simple Case 1: Configure a String object
  • First we configure the DSCS so that it knows about the property. Define your property as a static string in:
    • org.sakaiproject.component.configuration.properties.api.ConfigurationProperties
  • It has to be a unique value. We recommend that you use the package name from the class where the property lives, and append the property name:
    • e.g.
      Code Block
      
      package org.sakaiproject.component.configuration.properties.api;
      
      	public interface ConfigurationProperties {
      
      		// Person's First Name
      		public static final String PERSON_FIRST_NAME = "org.sakaiproject.example.Person.FirstName";
      
      		// ...
      	}
      	
      
  • Now, modify the component-impl's components.xml file.
  • Find the following bean: "<bean id="org.sakaiproject.component.configuration.service.api.DynamicServerConfigurationService" and locate the "dynamicSakaiProperties" bean property. Then, add your configurable property to the map and assign it an initial value:
    • e.g.
      Code Block
      
      <property name="dynamicSakaiProperties">
      	<map>
      		<entry key="org.sakaiproject.example.Person.FirstName">
      			<value>Thomas</value>
      		</entry>
      	</map>
      </property>
      
  • The target class that wants to add a dynamically configurable property needs to implement "ConfigurationNotificationListener" and "ConfigurationProperties"
    • e.g.
      Code Block
      
      public class PersonImpl implements ConfigurationNotificationListener, ConfigurationProperties { ... }
      
  • The class needs to get the initial property value either at construction time or during a Spring init() method invocation.
  • Also, it needs to implement the ConfigurationNotificationListener API method "handleNotification" e.g. Code Block package org.sakaiproject.example.Person; public class PersonImpl implements ConfigurationNotificationListener, ConfigurationProperties { // ... private String firstName; private DynamicServerConfigurationService dynamicServerConfigurationService; // ... // Spring DSCS injection public void setDynamicServerConfigurationService(DynamicServerConfigurationService dynamicServerConfigurationService) { this.dynamicServerConfigurationService = dynamicServerConfigurationService; } // Spring init method public void init() { // Configuration Service dynamicServerConfigurationService.addNotificationListener(this, PERSON_FIRST_NAME); try { firstName = dynamicServerConfigurationService.getDynamicString(PERSON_FIRST_NAME); } catch (ConfigurationObjectNotFound e) { LOG.error("Was not able to find configuration property"); } catch (InvalidConfigurationKey e) { LOG.error("Provided invalid configuration key"); } } // Implementing ConfigurationNotificationListener API: handleNotification public void handleNotification(String configurationItemKey) { try { if(PERSON_FIRST_NAME.equals(configurationItemKey)) { firstName = dynamicServerConfigurationService.getDynamicString(PERSON_FIRST_NAME); } } catch (ConfigurationObjectNotFound e) { LOG.error("Was not able to find configuration property for key = " + configurationItemKey); } catch (InvalidConfigurationKey e) { LOG.error("Provided invalid configuration key = " + configurationItemKey); } } Case 2: Configure a custom object