This example covers Togglz integration which JSF, Primefaces, and Spring. The example web application displays customer information based on the state of the toggle/flag. The customer’s address is only displayed if the toggle/flag is enabled. The flag can be enabled and disabled from the Togglz administration console. You can find the source code here.
Maven Togglz Dependencies
Since our example is Maven based, the Togglz dependencies are declared in pom.xml. Our application uses Togglz’s Spring integration module (and not CDI).
Our example application’s Togglz feature definition is described in a Java enum file named CustomerFeatures which implements the Feature interface. Our example declares only one feature named FEATURE_ADDRESS. The optional @Label is used to specify a human readable label for the feature which is used in the Togglz Admin Console. While the @EnabledByDefault annotation is used to indicate the feature, FEATURE_ADDRESS, is enabled by default if no previous state of the feature toggle is persisted in the state repository.
The example Togglz configuration is specified in a Java class named ToggleConfiguration. It implements the TogglzConfig interface. This particular class configures the FeatureManager which is the central Togglz component that manages the state of our features. The methods, declared in ToggleConfiguration, serve the following functions:
- getFeatureClass: Returns the Java enum used in our example application, CustomerFeatures.
- getStateRepository: Returns the type of repository where the state of our toggle will be persisted. In our example, the state is persisted in a file named features.properties located in a temporary directory.
- getUserProvider: Returns the user who can access Togglz Admin Console to modify the state of the toggle (enabled or disabled). In our example, no security is enabled and anyone can access the admin page.
In this example, Customer and Address constitutes our data model. They are regular POJOs that come with their own attributes and a corresponding set of getters and setters.
In our example a Java bean named, ViewCustomersManagedBean, is used for storing data. It is accessed by our example JSF page, index.xtml, for displaying customer information. Since our example uses Spring for managing Togglz configuration, we use Spring annotations (@Controller and @Scope) instead of JSF annotations (@ManagedBean and @SessionScoped). Using @ManagedBean annotation with Spring causes problems in certain application containers.
The example JSF page, index.xhtml, displays customer name and address based on the toggle FEATURE_ADDRESS. If the toggle FEATURE_ADDRESS is enabled, customer is address otherwise not. The check for the toggle is performed by the following snippet.
Since we are using Servlet 3.0 (make sure your app/web server supports Servlet 3.0), no Togglz specific configuration changes are need in WEB-INF/web.xml file. The following web.xml contains configuration related to JSF and Spring.
Now if you container which doesn’t support Servlet 3.0 specification, you have to add the following declaration in your web.xml:
We specify the Spring configuration in a applicationContext.xml, located in WEB-INF. The name and the location of the Spring configuration file are specified in a context-param tag named contextConfigLocation. The context:annotation-config tag is used to activate annotations in beans already registered in the application context. While context:component-scan tag is used to activate Spring annotation scanning capability which allows to make use of annotations like @Controller, @Component, etc. Here is our example applicationContext.xml.
Standard face-config.xml doesn’t contain any information related to Togglz.
Building Maven Project
To build our Maven project, open a console and change directory to the project root. Once you are in the project root, execute the following command:
mvn clean install
If the project builds successfully, it should create a rest-helloworld.war file in the target directory.
Deploying in Tomcat
Here we will only talk about deploying the WAR file directly to a web server (instead of deploying it form Eclipse):
- Make sure you have started Tomcat by executing startup.bat script in the bin folder under Tomcat installed directory.
- Tomcat should start up at port 8080.
- Copy the togglz-jsf-example.war to the webapps folder under Tomcat installed directory.
- Access our example from http://localhost:8080/togglz-jsf-example
- Access Togglz Admin Console from http://localhost:8080/togglz-jsf-example/togglz
- Since the Address Feature toggle is enabled, its status is green. Click the action button (gear) to change the state of the Address Feature toggle.
- Change the state by unchecking the Enabled checkbox and clicking Save.
- The state of the Address Feature toggle is red and disabled.
- Now access or example again from http://localhost:8080/togglz-jsf-example/
- You will notice the address column is missing.