DSCS Usage Case 1

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.

    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.

    <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.

    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.

    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); } }