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The REST Plugin

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• Fully implements Ruby on Rails REST-style URLs
• Supports XML-free development, without requiring annotations
• Built-in serialization and deserialization support for XML and JSON
• Automatic error handling
• Type-safe configuration of the HTTP response
• Automatic conditional GET support

Usage

As with the Codebehind Plugin, the first step is to tell the plugin where to find your resource action classes. Modify the configuration of your Struts 2 filter in web.xml and add the 'actionPackages' init-param like so:

{snippet:url=struts2/apps/rest-showcase/src/main/webapp/WEB-INF/web.xml|id=filter|lang=xml}

To set other Struts properties, add other init-params. For example to set devMode to true, add:

  <!-- ... -->
  <init-param>
    <param-name>struts.devMode</param-name>
    <param-value>true</param-value>
  </init-param>
</filter>

Next, create Create Java objects ending in "Controller" in the configured package. The "Controller" suffix is used to distinguish REST action resources from regular Struts 2 actions, although it is completely optional and they are functionally the same. Now, add in methods to handle the various requests. For example, the following resource action will support /orders/34 GET and PUT requests:

package org.apache.struts2.rest.example;

@Namespace("")
public class OrdersController implements ModelDriven<Order> {

    private OrderManager orderManager;
    private String id;
    private Order model;

    // Handles /orders/{id} GET requests
    public HttpHeaders show() {
        model = orderManager.findOrder(id);
        return new DefaultHttpHeaders("show")
            .withETag(model.getUniqueStamp())
            .lastModified(model.getLastModified());
    }

    // Handles /orders/{id} PUT requests
    public String update() {
        orderManager.updateOrder(model);
        return "update";
    }

    // getters and setters
}

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struts.rest.handlerOverride.xml=myXml

struts.xml

Because the REST plugin uses the Convention plugin, some settings need to be set in struts.xml:

<constant name="struts.convention.action.suffix" value="Controller"/>
<constant name="struts.convention.action.mapAllMatches" value="true"/>
<constant name="struts.convention.default.parent.package" value="rest-default"/>

Example

The plugin ships with a struts2-rest-showcase application that demonstrates a simple REST web program.

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The following settings can be customized. See the developer guide.
For more configuration options see the Convention Plugin Documentation

Installation

This plugin can be installed by copying the plugin jar into your application's /WEB-INF/lib directory. The REST plugin is dependent on the Codebehind Convention Plugin, so if aren't using a build system that supports transitive dependencies like Maven 2, you will need to add that plugin as well.

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