Grizzly Jersey swallowing exceptions

Question

I'm building a Jersey Moxy service using the quickstart archetype at the end. My code works fine and I can get some JSON returned. However as I'm developing, if I make a mistake, say the request handler has an unsupported type, I will get an empty 500 response, which makes debugging difficult. For example, if I decorate an attribute incorrectly with @XmlElementRef, I will get a response like:

$ curl -i http://localhost:8080/myapp/test
HTTP/1.1 500 Internal Server Error
Date: Thu, 05 Sep 2013 10:27:55 GMT
Connection: close
Content-Length: 0

The server will act as if nothing is wrong:

Sep 5, 2013 11:27:46 AM org.glassfish.grizzly.http.server.HttpServer start
INFO: [HttpServer] Started.
Jersey app started with WADL available at http://localhost:8080/application.wadl
Hit enter to stop it...

I tried using a log config file with:

-Djava.util.logging.config.file=log.conf

This produces plenty of output, but still doesn't show any kind of exception.

I've tried looking into Grizzly config but I can't find a way turn off graceful error handling. Ideally I would like the server to throw an exception. Any suggestions on what I'm missing?

Here's my main code:

import org.glassfish.grizzly.http.server.HttpServer;
import org.glassfish.jersey.grizzly2.httpserver.GrizzlyHttpServerFactory;
import org.glassfish.jersey.moxy.json.MoxyJsonConfig;
import org.glassfish.jersey.server.ResourceConfig;

import javax.ws.rs.ext.ContextResolver;
import javax.ws.rs.ext.Provider;

import java.io.IOException;
import java.net.URI;
import java.util.*;

public class Main {
    // Base URI the Grizzly HTTP server will listen on
    public static final String BASE_URI = "http://localhost:8080/";

    /**
     * Starts Grizzly HTTP server exposing JAX-RS resources defined in this application.
  * @return Grizzly HTTP server.
   */
   public static HttpServer startServer() {
       // create a resource config that scans for JAX-RS resources and providers
       // in com.myapp package
       final ResourceConfig rc = new ResourceConfig().packages("com.myapp").registerInstances(new JsonMoxyConfigurationContextResolver());

       // create and start a new instance of grizzly http server
       // exposing the Jersey application at BASE_URI
       return GrizzlyHttpServerFactory.createHttpServer(URI.create(BASE_URI), rc);
   }

   /**
    * Main method.
     * @param args
  * @throws IOException
   */
   public static void main(String[] args) throws IOException {
       final HttpServer server = startServer();
       System.out.println(String.format("Jersey app started with WADL available at "
               + "%sapplication.wadl\nHit enter to stop it...", BASE_URI));
       System.in.read();
       server.stop();
   }

   @Provider
   final static class JsonMoxyConfigurationContextResolver implements ContextResolver<MoxyJsonConfig> {

       @Override
       public MoxyJsonConfig getContext(Class<?> objectType) {
           final MoxyJsonConfig configuration = new MoxyJsonConfig();

           Map<String, String> namespacePrefixMapper = new HashMap<String, String>(1);
           namespacePrefixMapper.put("http://www.w3.org/2001/XMLSchema-instance", "xsi");

           configuration.setNamespacePrefixMapper(namespacePrefixMapper);
           configuration.setNamespaceSeparator(':');

           return configuration;
       }
   }
}

The code is almost identical to the example here:

https://github.com/jersey/jersey/tree/2.2/examples/json-moxy/src/main/java/org/glassfish/jersey/examples/jsonmoxy

Full archetype generation I used:

mvn archetype:generate -DarchetypeArtifactId=jersey-quickstart-grizzly2 \
-DarchetypeGroupId=org.glassfish.jersey.archetypes -DinteractiveMode=false \
-DgroupId=com.myapp -DartifactId=yarese-service -Dpackage=com.myapp \
-DarchetypeVersion=2.2

Suggestions gratefully received.

Answer 1

The exception is not getting propagated to the Grizzly layer, so it should be logged by Jersey. I haven't found what kind of Logger you have to enable, but looks like custom ExceptionMapper could help.

import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.Response;
import javax.ws.rs.ext.ExceptionMapper;
import javax.ws.rs.ext.Provider;
import org.glassfish.grizzly.utils.Exceptions;

@Provider
public class MyExceptionMapper  implements
        ExceptionMapper<WebApplicationException> {
    @Override
    public Response toResponse(WebApplicationException ex) {
        return Response.status(500).entity(Exceptions.getStackTraceAsString(ex)).type("text/plain")
                .build();
    }
}

Answer 2

As you've seen, Grizzly uses java.util.logging. If you'd like to see the stacktrace, you need to make sure the levels are correctly set in your log.conf file.

Here are settings that have worked for me in the past:

handlers=java.util.logging.ConsoleHandler
java.util.logging.ConsoleHandler.level=ALL
.level=ALL
org.glassfish.level=CONFIG