Implementing a RESTful Service with Reflection¶

Prerequisites¶

This section builds off the example in the previous section Implementing a RESTful Service with Maps.

Create a new java bean¶

1. The use of ReflectiveResource requires we have an underlying object to to work with. Create a class named Hello in the package org.geoserver.hellorest:

   package org.geoserver.hellorest;
   
   public class Hello {
   
      String message;
   
      public Hello( String message ) {
          this.message = message;
      }
   
      public String getMessage() {
         return message;
      }
   }
   

Create a new resource class¶

1. Create a new class called HelloReflectiveResource in the package org.geoserver.hellorest, which extends from ReflectiveResource:

   package org.geoserver.hellorest;
   
   import org.geoserver.rest.ReflectiveResource;
   
   public class HelloReflectiveResource extends ReflectiveResource {
   
      @Override
      protected Object handleObjectGet() throws Exception {
          return null;
      }
   }
   

2. The first method to implement is handleObjectGet(). The purpose of this method is to return the underlying object representing the resource. In this case, an instance of the Hello class created in the previous step.

   @Override
   protected Object handleObjectGet() throws Exception {
      return new Hello( "Hello World" );
   }
   

Update the application context¶

1. The next step is to update an application context and tell GeoServer about the new resource created in the previous section. Update the applicationContext.xml file so that it looks like the following:

    <!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd">
   
    <beans>
       <bean id="hello" class="org.geoserver.hellorest.HelloResource"/>
       <bean id="helloMap" class="org.geoserver.hellorest.HelloMapResource"/>
       <bean id="helloReflective" class="org.geoserver.hellorest.HelloReflectiveResource"/>
   
       <bean id="helloMapping" class="org.geoserver.rest.RESTMapping">
          <property name="routes">
             <map>
               <entry>
                 <key><value>/hello.{format}</value></key>
                 <!--value>hello</value-->
                 <!--value>helloMap</value-->
                 <value>helloReflective</value>
               </entry>
            </map>
         </property>
       </bean>
   
   </beans>
   

   There are two things to note above. The first is the addition of the helloReflective bean. The second is a change to the helloMapping bean, which now maps to the helloReflective bean.

Test¶

1. Create a new test class called HelloReflectiveResourceTest in the package org.geoserver.hellorest, which extends from org.geoserver.test.GeoServerTestSupport:

   package org.geoserver.hellorest;
   
   import org.geoserver.test.GeoServerTestSupport;
   
   public class HelloReflectiveResourceTest extends GeoServerTestSupport {
   
   }
   

2. Add a test named testGetAsXML() which makes a GET request for /rest/hello.xml:

   ...
   
   import org.w3c.dom.Document;
   import org.w3c.dom.Node;
   
   ...
   
      public void testGetAsXML() throws Exception {
        //make the request, parsing the result as a dom
        Document dom = getAsDOM( "/rest/hello.xml" );
   
        //print out the result
        print(dom);
   
        //make assertions
        Node message = getFirstElementByTagName( dom, "message");
        assertNotNull(message);
        assertEquals( "Hello World", message.getFirstChild().getNodeValue() );
      }
   

3. Add a second test named testGetAsJSON() which makes a GET request for /rest/hello.json:

   ...
   
   import net.sf.json.JSON;
   import net.sf.json.JSONObject;
   
   ...
   
      public void testGetAsJSON() throws Exception {
        //make the request, parsing the result into a json object
        JSON json = getAsJSON( "/rest/hello.json");
   
        //print out the result
        print(json);
   
        //make assertions
        assertTrue( json instanceof JSONObject );
        JSONObject hello = ((JSONObject) json).getJSONObject( "org.geoserver.hellorest.Hello" );
        assertEquals( "Hello World", hello.get( "message" ) );
      }
   

4. Build and test the hello_test module:

   [hello_rest]% mvn clean install -Dtest=HelloMapReflectiveResourceTest