MonetaDropwizardApplication.java

/*
 * This software is licensed under the Apache License, Version 2.0
 * (the "License") agreement; you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.moneta.config.dropwizard;

import io.dropwizard.Application;
import io.dropwizard.setup.Bootstrap;
import io.dropwizard.setup.Environment;
import net.admin4j.ui.servlets.MemoryMonitorStartupServlet;

import org.apache.commons.lang.ArrayUtils;
import org.eclipse.jetty.servlet.BaseHolder.Source;
import org.eclipse.jetty.servlet.FilterHolder;
import org.eclipse.jetty.servlet.Holder;
import org.eclipse.jetty.servlet.ServletHolder;
import org.force66.correlate.RequestCorrelationFilter;
import org.moneta.MonetaPerformanceFilter;
import org.moneta.MonetaServlet;
import org.moneta.MonetaTopicListServlet;
import org.moneta.config.MonetaConfiguration;

import com.codahale.metrics.JmxReporter;

/**
 * Dropwizard configuration for Moneta
 * @author D. Ashmore
 *
 */
public class MonetaDropwizardApplication extends
Application<MonetaDropwizardConfiguration> {

	protected static boolean containsConfiguration(String[] args) {
		for (String arg : args) {
			if (arg.endsWith(".yaml") || arg.endsWith(".yml")
					|| arg.endsWith(".json")) {
				return true;
			}
		}
		return false;
	}

	public static void main(String[] args) throws Exception {
		String[] localArgs = args;
		if (!containsConfiguration(args)) {
			// Add default config if nothing specified
			localArgs = (String[]) ArrayUtils.add(args, "/moneta-config.yaml");
		}
		new MonetaDropwizardApplication().run(localArgs);
	}

	@Override
	public void initialize(Bootstrap<MonetaDropwizardConfiguration> bootstrap) {
		bootstrap.setConfigurationSourceProvider(new MonetaConfigurationSourceProvider());
		super.initialize(bootstrap);
	}

	@Override
	public void run(MonetaDropwizardConfiguration configuration,
			Environment environment) throws Exception {

		/*
		 * The ServletHolder allows you to specify init parameters and other
		 * servlet configuration itmes in the web.xml. Setting the order means
		 * that the servlet is initialized on startup; by default it is not.
		 */
		ServletHolder topicHolder = new ServletHolder(Source.EMBEDDED);
		topicHolder.setHeldClass(MonetaServlet.class);
		topicHolder.setInitOrder(0);
		topicHolder.setInitParameter(
				MonetaServlet.CONFIG_IGNORED_CONTEXT_PATH_NODES, "moneta,topic");
		environment.getApplicationContext()
		.getServletHandler()
		.addServletWithMapping(topicHolder, "/moneta/topic/*");

		// Will be initialized on first use by default.
		environment.getApplicationContext()
		.addServlet(MonetaTopicListServlet.class, "/moneta/topics/*");

		/*
		 * Install thread contention monitoring -- withdrawn after issue with
		 * Jetty discovered.
		 */
		// ServletHolder threadContentionHolder = new
		// ServletHolder(Source.EMBEDDED);
		// threadContentionHolder.setHeldClass(ThreadMonitorStartupServlet.class);
		// threadContentionHolder.setInitOrder(0);
		// environment.getApplicationContext()
		// .getServletHandler()
		// .addServlet(threadContentionHolder);

		/*
		 * Install memory alert monitoring
		 */
		ServletHolder memoryAlertHolder = new ServletHolder(Source.EMBEDDED);
		memoryAlertHolder.setHeldClass(MemoryMonitorStartupServlet.class);
		memoryAlertHolder.setInitOrder(0);
		environment.getApplicationContext()
		.getServletHandler()
		.addServlet(memoryAlertHolder);

		/*
		 * Install the performance filter
		 */
		FilterHolder perfFilterHolder = new FilterHolder(Holder.Source.EMBEDDED);
		perfFilterHolder.setHeldClass(MonetaPerformanceFilter.class);
		perfFilterHolder.setInitParameter(
				MonetaPerformanceFilter.PARM_MAX_TRNASACTION_TIME_THRESHOLD_IN_MILLIS,
				"3000");
		environment.getApplicationContext()
		.addFilter(perfFilterHolder, "/moneta/*", null);

		/*
		 * Install RequestCorrelation filter so I can get a correlation id in
		 * the logs
		 */
		FilterHolder correlationFilterHolder = new FilterHolder(
				Holder.Source.EMBEDDED);
		correlationFilterHolder.setHeldClass(RequestCorrelationFilter.class);

		// Install healthchecks
		MonetaConfiguration config = new MonetaConfiguration();
		for (String checkName : config.getHealthChecks()
				.keySet()) {
			environment.healthChecks()
			.register(checkName, config.getHealthChecks()
					.get(checkName));
		}

		final JmxReporter jmxReporter = JmxReporter.forRegistry(
				environment.metrics())
				.build();
		jmxReporter.start();
	}

}