eu.agilejava.snoop.scan.SnoopClient.java Source code

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Here is the source code for eu.agilejava.snoop.scan.SnoopClient.java

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/*
 * The MIT License
 *
 * Copyright 2015 Ivar Grimstad (ivar.grimstad@gmail.com).
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package eu.agilejava.snoop.scan;

import com.fasterxml.jackson.dataformat.yaml.snakeyaml.Yaml;
import java.io.IOException;
import java.net.URI;
import java.util.Calendar;
import java.util.Map;
import java.util.logging.Logger;
import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;
import javax.annotation.Resource;
import javax.ejb.ScheduleExpression;
import javax.ejb.Singleton;
import javax.ejb.Startup;
import javax.ejb.Timeout;
import javax.ejb.Timer;
import javax.ejb.TimerConfig;
import javax.ejb.TimerService;
import javax.websocket.ClientEndpoint;
import javax.websocket.ContainerProvider;
import javax.websocket.DeploymentException;
import javax.websocket.OnMessage;
import javax.websocket.Session;
import javax.websocket.WebSocketContainer;

/**
 * Registers with Snoop and gives heartbeats every 10 second.
 *
 * @author Ivar Grimstad (ivar.grimstad@gmail.com)
 */
@ClientEndpoint
@Singleton
@Startup
public class SnoopClient {

    private static final Logger LOGGER = Logger.getLogger("eu.agilejava.snoop");
    private static final String DEFAULT_BASE_URI = "ws://localhost:8080/snoop-service/";
    private static final String REGISTER_ENDPOINT = "snoop";
    private static final String STATUS_ENDPOINT = "snoopstatus/";

    private String serviceUrl;
    private String applicationName;

    @Resource
    private TimerService timerService;

    @PostConstruct
    private void init() {

        LOGGER.config("Checking if snoop is enabled");

        if (SnoopExtensionHelper.isSnoopEnabled()) {

            readProperties();

            if (applicationName != null) {
                LOGGER.config(() -> "Registering " + applicationName);
                register(applicationName);
            } else {
                LOGGER.config(() -> "Registering with name from annotation: " + applicationName);
                register(SnoopExtensionHelper.getApplicationName());
            }

        } else {
            LOGGER.config("Snoop is not enabled. Use @EnableSnoopClient!");
        }
    }

    public void register(final String clientId) {
        sendMessage(REGISTER_ENDPOINT, clientId);

        ScheduleExpression schedule = new ScheduleExpression();
        schedule.second("*/10").minute("*").hour("*").start(Calendar.getInstance().getTime());

        TimerConfig config = new TimerConfig();
        config.setPersistent(false);

        Timer timer = timerService.createCalendarTimer(schedule, config);

        LOGGER.config(() -> timer.getSchedule().toString());
    }

    /**
     * Handles incoming message.
     *
     * @param session The WebSocket session
     * @param message The message
     */
    @OnMessage
    public void onMessage(Session session, String message) {
        LOGGER.config(() -> "Message: " + message);
        sendMessage(STATUS_ENDPOINT + applicationName, "UP");
    }

    @Timeout
    public void health(Timer timer) {
        LOGGER.config(() -> "health update: " + Calendar.getInstance().getTime());
        LOGGER.config(() -> "Next: " + timer.getNextTimeout());
        sendMessage(STATUS_ENDPOINT + applicationName, "UP");
    }

    /**
     * Sends message to the WebSocket server.
     *
     * @param endpoint The server endpoint
     * @param msg The message
     * @return a return message
     */
    private String sendMessage(String endpoint, String msg) {

        LOGGER.config(() -> "Sending message: " + msg);

        String returnValue = "-1";
        try {
            WebSocketContainer container = ContainerProvider.getWebSocketContainer();
            String uri = serviceUrl + endpoint;
            Session session = container.connectToServer(this, URI.create(uri));
            session.getBasicRemote().sendText(msg != null ? msg : "");
            returnValue = session.getId();

        } catch (DeploymentException | IOException ex) {
            LOGGER.warning(ex.getMessage());
        }

        return returnValue;
    }

    @PreDestroy
    private void deregister() {

        LOGGER.config(() -> "Deregistering " + applicationName);
        sendMessage(STATUS_ENDPOINT + applicationName, "OUT_OF_SERVICE");
    }

    private void readProperties() {
        Yaml yaml = new Yaml();
        Map<String, Object> props = (Map<String, Object>) yaml
                .load(this.getClass().getResourceAsStream("/application.yml"));

        Map<String, String> snoopConfig = (Map<String, String>) props.get("snoop");

        applicationName = snoopConfig.get("applicationName");
        LOGGER.config(() -> "application name: " + applicationName);

        serviceUrl = snoopConfig.get("serviceUrl") != null ? snoopConfig.get("serviceUrl") : DEFAULT_BASE_URI;
    }
}