RESTEasy will not map my Spring bean with custom Spring ContextLoader

Question

• RESTEasy 2.0.1GA
• Java 1.6
• Spring 3.0.3

I have tried everything I can, and cannot make head or tail of what's going on. I have a Spring MVC application, however I'd like to have some RESTEasy endpoints available outside the Spring MVC app, but in the same container, ultimately being able to wire in the same beans.

As a first step, I'm simply trying to stand-up RESTEasy inside the container, serving requests from a Spring-configured bean. I have tried the boilerplate from the instructions and have also tried manual setup, to no avail.

Bean

@Resource
@Path("/")
public class NeighborComparison {

    private String foo;

    @GET @Path(value="customer") @Produces("text/plain")
    public String getNeighborComparison() {
        return "foo";
    }
}

web.xml

<context-param>
    <param-name>resteasy.servlet.mapping.prefix</param-name>
    <param-value>/api</param-value>
</context-param>

<listener>
    <listener-class>org.jboss.resteasy.plugins.server.servlet.ResteasyBootstrap</listener-class>
</listener>

<!-- NOT configuring SpringContextLoaderListener because I declare my own, so if I do, everything
     blows up, plus  all it actually does is sanity check configuration -->
<listener>
    <listener-class>com.example.MyCustomContextLoaderListener</listener-class>
</listener>

<servlet>
    <servlet-name>Resteasy</servlet-name>
    <servlet-class>org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher</servlet-class>
</servlet>

<servlet-mapping>
    <servlet-name>Resteasy</servlet-name>
    <url-pattern>/api/*</url-pattern>
</servlet-mapping>

applicationContext.xml

<bean id="resteasy.providerFactory" class="org.jboss.resteasy.spi.ResteasyProviderFactory"
      factory-method="getInstance">
</bean>

<bean id="resteasy.dispatcher" class="org.jboss.resteasy.core.SynchronousDispatcher">
    <constructor-arg ref="resteasy.providerFactory"/>
</bean>

<bean id="resteasy.spring.bean.processor" class="org.jboss.resteasy.plugins.spring.SpringBeanProcessor">
    <description>
        Add Resources and @Providers to the appropriate places
        in Resteasy's infrastructure
    </description>
    <constructor-arg ref="resteasy.dispatcher"/>
</bean>

<bean id="neighborComparison" class="opower.api.customer.neighbor_comparison.NeighborComparison">
</bean>

According to the documentation, all I have to do is “manually register the RESTeasy BeanFactoryPostProcessor by allocating an instance of org.jboss.resteasy.plugins.spring.SpringBeanProcessor”. I believe this spring configuration does that.

Jetty starts and the app context spins up with no issues. Application works normally, however when I

> curl -H"Accept: text/plain" localhost:8080/ei/api/customer

("ei" is the application context). The log shows (this and only this):

2011-03-29 16:44:24,153 DEBUG [qtp-575315405-0] [EI] [] [asy.core.SynchronousDispatcher] PathInfo: /customer
2011-03-29 16:44:24,156 DEBUG [qtp-575315405-0] [EI] [] [asy.core.SynchronousDispatcher] Failed executing GET /customer
org.jboss.resteasy.spi.NotFoundException: Could not find resource for relative : /customer of full path: http://localhost:8080/ei/api/customer

Even if I could convince RESTEasy to show me the mappings, it seems that it's just not discovering my bean.

If I map it explicitly via the resteasy.resources context param, it works, though obviously doesn't have access to auto-wired Spring beans.

Anything else I can try? I have debug log on the entire RESTEasy codebase and I don't get any messages. I've also confirmed that Spring is, in fact, creating my bean, so it's just that RESTEasy isn't finding it.

Answer 1

Your resource class needs to be annotated with @Path annotation for RESTeasy to pick up on it during bootstrap:

@Path("/customer")
@Resource
public class NeighborComparison {

    @GET @Path("/{customerId}") @Produces("text/plain")
    public String getNeighborComparison(@PathParam("customerId") long customerId) {
        return "foo";
    }
}

Note the @Path("/{customerId}} annotation without which your @PathParam parameter would not have been mapped correctly, resulting in a pretty detailed exception (and an accompanying 500 response on the client side). Assuming the service is picked up by RESTeasy of course.

In addition if you don't use RESTeasy's SpringContextLoader, you have to make sure your SpringBeanProcessor instance is registered with the ApplicationContext. RESTeasy delegates to it by registering an ApplicationListener in SpringContextLoader:

  ApplicationListener listener = new ApplicationListener() {
     public void onApplicationEvent(ApplicationEvent event) {
        if (event instanceof ContextRefreshedEvent) {
           ContextRefreshedEvent cre = (ContextRefreshedEvent) event;
           ConfigurableListableBeanFactory autowireCapableBeanFactory = (ConfigurableListableBeanFactory) cre
                 .getApplicationContext().getAutowireCapableBeanFactory();
           new SpringBeanProcessor(dispatcher, registry, providerFactory)
                 .postProcessBeanFactory(autowireCapableBeanFactory);
        }
     }
  };
  configurableWebApplicationContext.addApplicationListener(listener);

If using a custom context loader and not the RESTEasy-provided one, this code has to appear somewhere in your context loader so that everything gets wired up. A bit convoluted, yeah. It is SpringBeanProcessor that goes through all Spring beans and registers with RESTeasy those that have a @Path annotation somewhere in their hierarchy (type and their corresponding interfaces).