Dropwizard instrumentation of Guice beans annotated with @timed

ApplicationGuiceModule.java

package com.developerb.dropbot;

import com.developerb.dropbot.instrumentation.MethodInvocationTimingInterceptor;
import com.google.inject.AbstractModule;
import com.yammer.metrics.annotation.Timed;

import static com.google.inject.matcher.Matchers.annotatedWith;
import static com.google.inject.matcher.Matchers.any;

/**
 * @author Kim A. Betti
 */
public class DropBotModule extends AbstractModule {

    @Override
    protected void configure() {
        bindInterceptor(any(), annotatedWith(Timed.class), new MethodInvocationTimingInterceptor());

        // ... 
    }

}

MethodInvocationTimingInterceptor.java

package com.developerb.dropbot.instrumentation;

import com.yammer.metrics.Metrics;
import com.yammer.metrics.annotation.Timed;
import com.yammer.metrics.core.MetricName;
import com.yammer.metrics.core.Timer;
import com.yammer.metrics.core.TimerContext;
import org.aopalliance.intercept.MethodInterceptor;
import org.aopalliance.intercept.MethodInvocation;

import static com.yammer.metrics.core.MetricName.chooseGroup;
import static com.yammer.metrics.core.MetricName.chooseName;
import static com.yammer.metrics.core.MetricName.chooseType;
import static java.util.concurrent.TimeUnit.MILLISECONDS;
import static java.util.concurrent.TimeUnit.SECONDS;

/**
 * Based on InstrumentedResourceMethodDispatchProvider
 * @author Kim A. Betti
 */
public class MethodInvocationTimingInterceptor implements MethodInterceptor {

    @Override
    public Object invoke(MethodInvocation invocation) throws Throwable {
        Class<?> clazz = invocation.getThis().getClass();
        Timed annotation = invocation.getMethod().getAnnotation(Timed.class);

        MetricName metricName = buildMetric(invocation, clazz, annotation);
        Timer timer = buildTimer(annotation, metricName);
        return proceedInvocationWithTimer(invocation, timer);
    }

    private MetricName buildMetric(MethodInvocation invocation, Class<?> clazz, Timed annotation) {
        String group = chooseGroup(annotation.group(), clazz);
        String type = chooseType(annotation.type(), clazz);
        String name = chooseName(annotation.name(), invocation.getMethod());
        return new MetricName(group, type, name);
    }

    private Timer buildTimer(Timed annotation, MetricName metricName) {
        return Metrics.newTimer(metricName,
                annotation.durationUnit() == null ? MILLISECONDS : annotation.durationUnit(),
                annotation.rateUnit() == null ? SECONDS : annotation.rateUnit());
    }

    private Object proceedInvocationWithTimer(MethodInvocation invocation, Timer timer) throws Throwable {
        TimerContext context = timer.time();
        try {
            return invocation.proceed();
        }
        finally {
            context.stop();
        }
    }

}

PostenZipCodeClient.java

package com.developerb.dropbot.bot.posten;

import com.sun.jersey.api.client.WebResource;
import com.yammer.dropwizard.client.JerseyClient;
import com.yammer.metrics.annotation.Timed;
import org.codehaus.jackson.annotate.JsonCreator;
import org.codehaus.jackson.annotate.JsonProperty;
import org.hibernate.validator.constraints.NotEmpty;

import javax.inject.Inject;

import static javax.ws.rs.core.MediaType.APPLICATION_ATOM_XML_TYPE;

/**
 * Proof of concept client for Bring's zip code service.
 * Reference: http://developer.bring.com/learn/postalcode/apireference.html
 * @author Kim A. Betti
 */
public class PostenZipCodeClient implements ZipCodeClient {

    private final WebResource api;

    @Inject
    public PostenZipCodeClient(JerseyClient client) {
        api = client.resource("http://fraktguide.bring.no/fraktguide/api/postalCode.json");
    }

    @Override
    @Timed(group="external", type="posten-zip-code-service", name="reverse-lookup")
    public String resolve(String zipCode) {
        PostenResult response = api.queryParam("country", "no")
                                   .queryParam("pnr", zipCode)
                                   .accept(APPLICATION_ATOM_XML_TYPE)
                                   .get(PostenResult.class);

        if (response.isInvalid()) {
            throw new InvalidZipCodeException(zipCode, "Norway");
        }
        else {
            return response.place;
        }
    }

    private static class PostenResult {

        @NotEmpty
        private final String place;
        private final boolean valid;

        @JsonCreator
        public PostenResult(@JsonProperty("result") String place,
                            @JsonProperty("valid") boolean valid) {

            this.valid = valid;
            this.place = place;
        }

        public String getPlace() {
            return place;
        }

        public boolean isInvalid() {
            return !valid;
        }

    }

}

sample-output.js

{
  "external.posten-zip-code-service" : {
    "reverse-lookup" : {
      "type" : "timer",
      "duration" : {
        "unit" : "milliseconds",
        "min" : 39.74018,
        "max" : 5474.089895,
        "mean" : 1634.8598794000002,
        "std_dev" : 2355.3624835465334,
        "median" : 219.17689,
        "p75" : 3913.0017159999998,
        "p95" : 5474.089895,
        "p98" : 5474.089895,
        "p99" : 5474.089895,
        "p999" : 5474.089895
      },
      "rate" : {
        "unit" : "seconds",
        "count" : 5,
        "mean" : 0.0012641292163691517,
        "m1" : 0.015991117074135343,
        "m5" : 0.0033057369185648107,
        "m15" : 0.001164697404800008
      }
    }
  }
}