Servlet context injection fail while using jersey test framework

Question

I'm beginning with jersey and trying to get freemarker working with it using TDD. I want to make a ViewProcessor for my templates, but fail to inject the servlet context in the class.

Here is the class code :

@Provider
public class myProcessor implements ViewProcessor<Template> {

    [...]
   
    @Context
    public ServletContext myContext;

    [...]

 freemarkerConfiguration.setTemplateLoader(
       new WebappTemplateLoader(myContext,
           myContext.getInitParameter("freemarker.template.path")));

    [...]
    }

And here is the test code :

public class myProcessorTest extends JerseyTest {
   
    public static myProcessor mp;
   
    public myProcessorTest() throws Exception{
        super(new WebAppDescriptor.Builder("com.domain").build());
    }
   
    @Test
    public void firstTest(){
        mp = new myProcessor();
        String path = new String("test.ftl");
        Template template = mp.resolve(path);
        assertNotNull(template);
    }
}

I use maven with dependencies as follow:

<dependency>
    <groupId>com.sun.jersey.jersey-test-framework</groupId>
    <artifactId>jersey-test-framework-grizzly</artifactId>
    <version>1.5-SNAPSHOT</version>
    <scope>test</scope>
</dependency>

My code runs fine when I deploy to my local jetty server. But if I want to test the code in my IDE, it failed to inject the servlet context (@Context) : myContext is null when I run the test :/

I think I'm missing something, but I'm a complete beginner with servlet world.

Answer 1

Here's a technique for testing a specific resource class, using Jersey Test Framework, with servlet support. Also demonstrates how to customize the ServletContext.

import javax.servlet.ServletContext;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.Feature;
import javax.ws.rs.core.FeatureContext;
import org.glassfish.jersey.server.ResourceConfig;
import org.glassfish.jersey.servlet.ServletContainer;
import org.glassfish.jersey.test.DeploymentContext;
import org.glassfish.jersey.test.JerseyTest;
import org.glassfish.jersey.test.ServletDeploymentContext;
import org.glassfish.jersey.test.TestProperties;
import org.glassfish.jersey.test.grizzly.GrizzlyWebTestContainerFactory;
import org.glassfish.jersey.test.spi.TestContainerException;
import org.glassfish.jersey.test.spi.TestContainerFactory;

import static org.mockito.Mockito.mock;

/**
 * A base class for testing web resources.
 */
public abstract class WebResourceTest extends JerseyTest {

    /**
     * Creates a JAX-RS resource configuration for test purposes.
     */
    @Override
    protected abstract ResourceConfig configure();

    /**
     * Creates a test container factory with servlet support.
     */
    @Override
    protected TestContainerFactory getTestContainerFactory() throws TestContainerException {
        return new GrizzlyWebTestContainerFactory();
    }

    /**
     * Configures a deployment context for JAX-RS.
     */
    @Override
    protected DeploymentContext configureDeployment() {
        ResourceConfig app = configure();
        app.register(new Feature() {
            @Context
            ServletContext servletContext;

            @Override
            public boolean configure(FeatureContext context) {
                servletContext.setAttribute("example", new Object());
                return true;
            }
        });
        return ServletDeploymentContext.forServlet(new ServletContainer(app)).build();
    }
}

A usage example:

import org.glassfish.jersey.server.ResourceConfig;
import javax.ws.rs.core.Context;
import javax.ws.rs.Path;
import javax.ws.rs.GET;
import javax.ws.rs.core.Response;
import static org.mockito.Mockito.spy;
import static org.testng.Assert.assertEquals;
import static org.junit.Assert.*;

public class MyResourceTest extends WebResourceTest {

    private MyResource resource;

    @Override
    protected ResourceConfig configure() {
        resource = spy(new MyResource());
        return new ResourceConfig().register(resource);
    }

    @Test
    public void testSomething() {
        Response r = target("/myresource").request().get();
        assertEquals(200, r.getStatus());
        assertEquals(1, resource.count);
    }
}

@Path("/myresource")
public class MyResource {
    int count = 0;

    @Context
    protected ServletContext servletContext;

    @GET
    public void get() {
       Object attr = servletContext.getAttribute("example");
       count++;
    }
}