Hystrix publisher

gistfile1.txt

package br.com.oobj.me.hystrix;

import io.prometheus.client.exporter.MetricsServlet;

import org.apache.commons.lang3.StringUtils;
import org.apache.log4j.Logger;
import org.dom4j.Element;
import org.eclipse.jetty.server.Server;
import org.eclipse.jetty.servlet.ServletContextHandler;
import org.eclipse.jetty.servlet.ServletHolder;

import com.netflix.hystrix.contrib.metrics.eventstream.HystrixMetricsStreamServlet;
import com.soundcloud.prometheus.hystrix.HystrixPrometheusMetricsPublisher;

/**
 * Servidor de publicacao de metricas coletadas pelo hystrix
 * 
 * @author Ricardo Faria
 *
 */
public class HystrixPublishServer {

	private final static Logger LOG = Logger.getLogger(HystrixPublishServer.class);

	private static final String NOME_STREAM = "/hystrix.stream";
	private static final String PORTA_PUBLICACAO = "porta";
	private static final String PROMETHEUS = "dashboard";
	private static final int PORTA_PADRAO = 7777;

	/**
	 * Element utilizado para definir a inicializacao do hystrix
	 * 
	 * @param element
	 */
	public HystrixPublishServer(Element element) {
		try {
			int porta = getPorta(element);
			boolean prometheusAtivado = isPrometheusAtivado(element);
			if(prometheusAtivado) {
				publicarPrometheus();
			}
			inicializarServer(porta, prometheusAtivado);
			LOG.info("Publicador de metricas do hystrix iniciado na porta "
					+ porta + ".");
		} catch (Exception e) {
			LOG.error("Falha ao publicar servidor de metricas do hystrix.", e);
		}
	}

	private int getPorta(Element element) {
		int porta = PORTA_PADRAO;
		String portaString = element.attributeValue(PORTA_PUBLICACAO);
		if (StringUtils.isNumeric(portaString)) {
			porta = Integer.valueOf(portaString);
		}
		return porta;
	}

	private boolean isPrometheusAtivado(Element element) {
		boolean ativado = false;
		String ativadoString = element.attributeValue(PROMETHEUS);
		ativado = Boolean.parseBoolean(ativadoString);
		return ativado;
	}

	
	private void publicarPrometheus(){
		HystrixPrometheusMetricsPublisher.register("bureau");

	}
	
	private void inicializarServer(int porta, boolean prometheusAtivado) throws Exception {
		Server server = new Server(porta);
		ServletContextHandler context = new ServletContextHandler(
				ServletContextHandler.NO_SESSIONS);
		server.setHandler(context);

		final HystrixMetricsStreamServlet servlet = new HystrixMetricsStreamServlet();
		final ServletHolder holder = new ServletHolder(servlet);
		context.addServlet(holder, NOME_STREAM);
		if(prometheusAtivado) {
			context.addServlet(new ServletHolder(new MetricsServlet()), "/metrics");
		}

		server.start();
	}
}