edu.stanford.epad.epadws.handlers.admin.ServerStatusHandler.java Source code

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/*******************************************************************************
 * Copyright (c) 2015 The Board of Trustees of the Leland Stanford Junior University
 * BY CLICKING ON "ACCEPT," DOWNLOADING, OR OTHERWISE USING EPAD, YOU AGREE TO THE FOLLOWING TERMS AND CONDITIONS:
 * STANFORD ACADEMIC SOFTWARE SOURCE CODE LICENSE FOR
 * "ePAD Annotation Platform for Radiology Images"
 *
 * This Agreement covers contributions to and downloads from the ePAD project ("ePAD") maintained by The Board of Trustees 
 * of the Leland Stanford Junior University ("Stanford"). 
 *
 * *   Part A applies to downloads of ePAD source code and/or data from ePAD. 
 *
 * *   Part B applies to contributions of software and/or data to ePAD (including making revisions of or additions to code 
 * and/or data already in ePAD), which may include source or object code. 
 *
 * Your download, copying, modifying, displaying, distributing or use of any ePAD software and/or data from ePAD 
 * (collectively, the "Software") is subject to Part A. Your contribution of software and/or data to ePAD (including any 
 * that occurred prior to the first publication of this Agreement) is a "Contribution" subject to Part B. Both Parts A and 
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 *
 * PART A. DOWNLOADING AGREEMENT - LICENSE FROM STANFORD WITH RIGHT TO SUBLICENSE ("SOFTWARE LICENSE").
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package edu.stanford.epad.epadws.handlers.admin;

import java.io.File;
import java.io.PrintWriter;
import java.net.InetAddress;
import java.text.DecimalFormat;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.Date;
import java.util.List;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.io.FileSystemUtils;
import org.eclipse.jetty.server.Request;
import org.eclipse.jetty.server.handler.AbstractHandler;

import edu.stanford.epad.common.util.EPADConfig;
import edu.stanford.epad.common.util.EPADLogger;
import edu.stanford.epad.dtos.TaskStatus;
import edu.stanford.epad.epadws.EPadWebServerVersion;
import edu.stanford.epad.epadws.Main;
import edu.stanford.epad.epadws.epaddb.EpadDatabase;
import edu.stanford.epad.epadws.handlers.HandlerUtil;
import edu.stanford.epad.epadws.models.EventLog;
import edu.stanford.epad.epadws.models.Plugin;
import edu.stanford.epad.epadws.models.User;
import edu.stanford.epad.epadws.processing.pipeline.PipelineFactory;
import edu.stanford.epad.epadws.processing.pipeline.task.EpadStatisticsTask;
import edu.stanford.epad.epadws.processing.pipeline.watcher.EPADSessionWatcher;
import edu.stanford.epad.epadws.processing.pipeline.watcher.QueueAndWatcherManager;
import edu.stanford.epad.epadws.security.EPADSession;
import edu.stanford.epad.epadws.security.EPADSessionOperations;
import edu.stanford.epad.epadws.service.DefaultEpadProjectOperations;
import edu.stanford.epad.epadws.service.PluginOperations;
import edu.stanford.epad.epadws.service.SessionService;

/**
 * <code>
 * curl -v -b JSESSIOND=<id> -X GET "http://<ip>:<port>/epad/status/"
 * </code>
 * 
 * @author martin
 */
public class ServerStatusHandler extends AbstractHandler {
    private static final EPADLogger log = EPADLogger.getInstance();

    private static final String INVALID_SESSION_TOKEN_MESSAGE = "Session token is invalid on status route";
    private static final String INTERNAL_EXCEPTION_MESSAGE = "Internal error getting server status";

    private static Long startTime = null;

    public ServerStatusHandler() {
        if (startTime == null)
            startTime = System.currentTimeMillis();
    }

    @Override
    public void handle(String s, Request request, HttpServletRequest httpRequest,
            HttpServletResponse httpResponse) {
        PrintWriter responseStream = null;
        int statusCode;

        httpResponse.setContentType("text/html");
        if (request != null) // In case handler is not called thru jetty
            request.setHandled(true);

        try {
            boolean debug = "true".equalsIgnoreCase(httpRequest.getParameter("system_debug"));
            responseStream = httpResponse.getWriter();
            boolean validSession = SessionService.hasValidSessionID(httpRequest);
            User user = null;
            String sessionID = null;
            String username = null;
            if (validSession) {
                sessionID = SessionService.getJSessionIDFromRequest(httpRequest);
                username = EPADSessionOperations.getSessionUser(sessionID);
                user = DefaultEpadProjectOperations.getInstance().getUser(username);
                long upTime = System.currentTimeMillis() - startTime;
                long upTimeHr = upTime / (1000 * 60 * 60);
                long remain = upTime % (1000 * 60 * 60);
                long upTimeMin = remain / (1000 * 60);
                long upTimeSec = remain % (1000 * 60);
                upTimeSec = upTimeSec / 1000;
                responseStream.println("<body  topmargin='10px' leftmargin='10px' width='900px'>");
                String path = httpRequest.getContextPath().replace("status/", "").replace("status", "");
                if (!path.endsWith("/"))
                    path = path + "/";
                responseStream.println("<a href=\"javascript:window.parent.location='" + path
                        + "Web_pad.html'\"><b>Back to ePAD</b></a>");
                if (Main.testPages && user != null && user.isAdmin())
                    responseStream.println("<div style='float:right'><a href=\"javascript:window.parent.location='"
                            + path + "test/index.jsp'\"><b>Test Pages</b></a></div>");
                responseStream.println("<hr>");
                responseStream.println("<h3><center>ePAD Server Status</center></h3>");
                responseStream.println("<hr>");
                responseStream.println("<b>ePAD server started:</b> " + new Date(startTime) + "<br>");
                responseStream.println("<b>ePAD server uptime:</b> " + upTimeHr + " hrs " + upTimeMin + " mins "
                        + upTimeSec + " secs<br>");
                responseStream.println("<br>");
            }
            if (!validSession)
                responseStream.println("Version: " + new EPadWebServerVersion().getVersion() + " Build Date: "
                        + new EPadWebServerVersion().getBuildDate() + " Build Host: "
                        + new EPadWebServerVersion().getBuildHost() + "<br>");
            if (validSession || debug) {
                responseStream.println("<b>Version:</b> " + new EPadWebServerVersion().getVersion()
                        + " <b>Build Date:</b> " + new EPadWebServerVersion().getBuildDate()
                        + " <b>Build Host:</b> " + new EPadWebServerVersion().getBuildHost() + "<br>");

                //responseStream.println("Plugin Version - interface:      " + EPadPlugin.PLUGIN_INTERFACE_VERSION + "<br>");
                //responseStream.println("Plugin Version - implementation: " + ePadPlugin.getPluginImplVersion() + "<br>");
                EpadDatabase epadDatabase = EpadDatabase.getInstance();
                responseStream.println("<table width=50%>");
                //responseStream.println("ePAD database startup time: " + epadDatabase.getStartupTime() + " ms, database version: " + epadDatabase.getEPADDatabaseOperations().getDBVersion() + "<br>");
                //Dcm4CheeDatabase dcm4CheeDatabase = Dcm4CheeDatabase.getInstance();
                //responseStream.println("<br>");
                //responseStream.println("DCM4CHEE database startup time: " + dcm4CheeDatabase.getStartupTime() + " ms" + "<br>");
                //responseStream.println("<br>");
                responseStream.println("<tr><td colspan=2><hr></td></tr>");
                responseStream.println(
                        "<tr><td><b>Config Server:</b></td><td nowrap>" + EPADConfig.xnatServer + "</td></tr>");
                responseStream.println("<tr><td><b>Config serverProxy:</b></td><td nowrap>"
                        + EPADConfig.getParamValue("serverProxy") + "</td></tr>");
                responseStream.println("<tr><td><b>Config webserviceBase:</b></td><td nowrap>"
                        + EPADConfig.getParamValue("webserviceBase") + "</td></tr>");
                responseStream.println("<tr><td><b>Hostname:</b></td><td>"
                        + InetAddress.getLocalHost().getHostName() + "</td></tr>");
                responseStream.println(
                        "<tr><td><b>IP Address:</b></td><td>" + EpadStatisticsTask.getIPAddress() + "</td></tr>");
                if (EPADSessionWatcher.diskspacealert) {
                    responseStream.println(
                            "<tr><td colspan=2><font size=+1 color=red><b>Low System Disk Space</b></font></td></tr>");
                }
                responseStream
                        .println("<style>tbody { display: block;max-height:440px;overflow-y:auto; } </style>");
                List<EventLog> recentLogs = new ArrayList<EventLog>();
                int free = EpadDatabase.getInstance().getEPADDatabaseOperations().getFreeConnections();
                int used = EpadDatabase.getInstance().getEPADDatabaseOperations().getUsedConnections();
                if ((user != null && user.isAdmin()) || debug) {
                    responseStream.println("<tr><td colspan=2><hr></td></tr>");
                    responseStream.println(
                            "<tr><td nowrap><b>Available DB Connections:</b></td><td>" + free + "</td></tr>");
                    responseStream.println("<tr><td><b>Used DB Connections:</b></td><td>" + used + "</td></tr>");
                    responseStream.println("<tr><td colspan=2><hr></td></tr>");
                    long freeHeap = Runtime.getRuntime().freeMemory();
                    long totalHeap = Runtime.getRuntime().totalMemory();
                    DecimalFormat df = new DecimalFormat("###,###,###");
                    responseStream.println(
                            "<tr><td><b>Available Heap Space:</b></td><td>" + df.format(freeHeap) + "</td></tr>");
                    responseStream.println(
                            "<tr><td><b>Total Heap Space:</b></td><td>" + df.format(totalHeap) + "</td></tr>");
                    responseStream.println("<tr><td colspan=2><hr></td></tr>");
                    try {
                        responseStream.println("<tr><td><b>dcm4chee Free Space: </b></td><td>"
                                + df.format(FileSystemUtils.freeSpaceKb(EPADConfig.dcm4cheeDirRoot) / 1024)
                                + " Mb</td></tr>");
                        responseStream.println("<tr><td><b>ePad Free Space: </b></td><td>"
                                + df.format(
                                        FileSystemUtils.freeSpaceKb(EPADConfig.getEPADWebServerBaseDir()) / 1024)
                                + " Mb</td></tr>");
                        responseStream.println("<tr><td><b>Tmp Free Space: </b></td><td>"
                                + df.format(
                                        FileSystemUtils.freeSpaceKb(System.getProperty("java.io.tmpdir")) / 1024)
                                + " Mb (Max Upload)</td></tr>");
                        if (new File("/var/lib/mysql").exists())
                            responseStream.println("<tr><td><b>Mysql DB Free Space: </b></td><td>"
                                    + df.format(FileSystemUtils.freeSpaceKb("/var/lib/mysql") / 1024)
                                    + " Mb</td></tr>");
                    } catch (Exception x) {
                    }
                    responseStream.println("<tr><td colspan=2><hr></td></tr>");
                    responseStream.println("<tr><td><b>Series Queue:</b></td><td>"
                            + QueueAndWatcherManager.dicomSeriesWatcherQueue.size() + "</td></tr>");
                    responseStream.println("<tr><td><b>PNG Queue:</b></td><td>"
                            + QueueAndWatcherManager.pngGeneratorTaskQueue.size() + "</td></tr>");
                    responseStream.println("<tr><td><b>AddToProject Queue:</b></td><td>"
                            + QueueAndWatcherManager.xnatSeriesWatcherQueue.size() + "</td></tr>");
                    responseStream.println("<tr><td colspan=2><hr></td></tr>");
                    responseStream.println("</table>");
                    List<Plugin> plugins = PluginOperations.getInstance().getPlugins();
                    responseStream.println("<br>");
                    responseStream.println("<b>Loaded Plugins:</b>");
                    responseStream.println("<br><table border=1 cellpadding=2><tr style='font-weight: bold;'>"
                            + "<td align=center>ID</td><td align=center>Name</td><td align=center>Description</td>"
                            + "<td align=center>Javaclass</td><td align=center>Enabled</td><td align=center>Status</td><td align=center>Modality</td></tr>");
                    for (Plugin plugin : plugins) {
                        responseStream.println("<tr><td>" + plugin.getPluginId() + "</td><td>" + plugin.getName()
                                + "</td><td>" + checkNull(plugin.getDescription(), "&nbsp;") + "</td>");
                        responseStream.println("<td>" + plugin.getJavaclass() + "</td><td>" + plugin.getEnabled()
                                + "</td><td>" + checkNull(plugin.getStatus(), "&nbsp;") + "</td><td>"
                                + checkNull(plugin.getModality(), "&nbsp;") + "</td></tr>");
                    }
                    responseStream.println("</table>");
                    responseStream.println("<br><b>Current Sessions: </b>");
                    Map<String, EPADSession> sessions = EPADSessionOperations.getCurrentSessions();
                    responseStream.println(
                            "<br><table border=1 cellpadding=2 ><tbody><tr style='font-weight: bold;'><td align=center>User</td><td align=center>Started</td><td align=center>Client</td><td align=center>Last Request</td><td align=center>Request Time</td></tr>");
                    for (String id : sessions.keySet()) {
                        String you = "";
                        if (id.equals(sessionID))
                            you = "*";
                        EPADSession session = sessions.get(id);
                        responseStream.println("<tr><td>" + session.getUsername() + you + "</td><td nowrap>"
                                + shortformat.format(session.getCreatedTime()) + "</td><td nowrap>"
                                + session.getRemoteHost() + "/" + session.getRemoteAddr() + "</td><td>"
                                + session.getLastRequest() + "</td><td nowrap>"
                                + shortformat.format(session.getLastActivity()) + "</td></tr>");
                    }
                    responseStream.println("</table>");
                    Collection<User> users = DefaultEpadProjectOperations.getUserCache();
                    responseStream.println("<br><b>Background Tasks: </b>");
                    responseStream.println(
                            "<br><table border=1 cellpadding=2 ><tbody><tr style='font-weight: bold;'><td align=center>User</td><td align=center>Task</td><td align=center>Start</td><td align=center>Complete</td><td align=center>Elapsed</td><td align=center>Target</td><td align=center>Status</td></tr>");
                    boolean empty = true;
                    for (User u : users) {
                        Collection<TaskStatus> tssCol = u.getCurrentTasks().values();
                        List<TaskStatus> tss = new ArrayList<TaskStatus>();
                        tss.addAll(tssCol);
                        Collections.sort(tss, new TSComparator());
                        for (TaskStatus ts : tss) {
                            responseStream
                                    .println("<tr><td>" + u.getUsername() + "</td><td>" + ts.type + "</td><td>"
                                            + ts.starttime + "</td><td>" + checkNull(ts.completetime, "In Process")
                                            + "</td><td>" + getDiff(getDate(ts.starttime), getDate(ts.completetime))
                                            + "</td><td>" + ts.target
                                            + "</td><td style='max-width:500px; max-height:40px; overflow-y:auto'>"
                                            + ts.status + "</td></tr>");
                            empty = false;
                        }
                    }
                    if (empty)
                        responseStream.println(
                                "<tr><td colspan=100% align=center>No background processes running</td></tr>");
                    responseStream.println("</tbody></table>");
                    if (free > 0 && !debug)
                        recentLogs = DefaultEpadProjectOperations.getInstance().getUseEventLogs("%", 0, 100);
                } else {
                    responseStream.println("<br><b>Background Tasks: </b>");
                    responseStream.println(
                            "<br><table border=1 cellpadding=2 ><tbody><tr style='font-weight: bold;'><td align=center>User</td><td align=center>Task</td><td align=center>Start</td><td align=center>Complete</td><td align=center>Elapsed</td><td align=center>Target</td><td align=center>Status</td></tr>");
                    Collection<TaskStatus> tssCol = user.getCurrentTasks().values();
                    List<TaskStatus> tss = new ArrayList<TaskStatus>();
                    tss.addAll(tssCol);
                    Collections.sort(tss, new TSComparator());
                    for (TaskStatus ts : tss) {
                        responseStream.println("<tr><td>" + user.getUsername() + "</td><td>" + ts.type + "</td><td>"
                                + ts.starttime + "</td><td>" + checkNull(ts.completetime, "In Process")
                                + "</td><td>" + getDiff(getDate(ts.starttime), getDate(ts.completetime))
                                + "</td><td>" + ts.target + "</td><td>" + ts.status + "</td></tr>");
                    }
                    if (tss.size() == 0)
                        responseStream.println(
                                "<tr><td colspan=100% align=center>No background processes running</td></tr>");
                    responseStream.println("</tbody></table>");
                    if (free > 0)
                        recentLogs = DefaultEpadProjectOperations.getInstance().getUseEventLogs(username, 0, 100);
                }
                responseStream.println("<br><b>Event Logs: </b>");
                responseStream.println(
                        "<br><table border=1 cellpadding=2><tbody><tr style='font-weight: bold;'><td align=center>Time</td><td align=center>User</td><td align=center>Action</td><td align=center>Project</td><td align=center >Target</td></tr>");
                for (EventLog elog : recentLogs) {
                    responseStream.println(
                            "<tr style='max-height:40px;'><td nowrap>" + dateformat.format(elog.getCreatedTime())
                                    + "</td><td>" + elog.getUsername() + "</td><td nowrap>" + elog.getFunction()
                                    + "</td><td nowrap>" + checkNull(elog.getProjectID(), "N/A")
                                    + "</td><td><div style='max-width:500px; max-height:40px; overflow-y:auto'>"
                                    + checkNull(elog.getTarget(), "N/A") + "</div></td></tr>");
                }
                responseStream.println("</tbody></table>");

                responseStream.println("</body>");
            }
            statusCode = HttpServletResponse.SC_OK;
        } catch (Throwable t) {
            log.warning(INTERNAL_EXCEPTION_MESSAGE, t);
            statusCode = HandlerUtil.internalErrorResponse(INTERNAL_EXCEPTION_MESSAGE, responseStream, log);
        }
        httpResponse.setStatus(statusCode);
    }

    public static String checkNull(String value, String defaultValue) {
        if (value == null)
            return defaultValue;
        else
            return value;
    }

    static SimpleDateFormat dateformat = new SimpleDateFormat("yyyyMMdd HH:mm:ss");

    public static Date getDate(String dateStr) {
        if (dateStr == null || dateStr.length() == 0)
            return new Date();
        try {
            return dateformat.parse(dateStr);
        } catch (Exception x) {
        }
        return null;
    }

    static SimpleDateFormat shortformat = new SimpleDateFormat("MM/dd HH:mm:ss");

    public static String getDiff(Date start, Date end) {
        if (start == null)
            return null;
        if (end == null)
            end = new Date();
        long ms = end.getTime() - start.getTime();
        String diff = ms / (1000 * 60) + " mins " + ms % (1000 * 60) / 1000 + " secs";
        return diff;
    }

    public class TSComparator implements Comparator<TaskStatus> {
        public int compare(TaskStatus o1, TaskStatus o2) {
            try {
                //            if (o2.completetime != null)
                //               return getDate(o2.completetime).compareTo(getDate(o1.completetime));
                //            else
                return getDate(o2.starttime).compareTo(getDate(o1.starttime));
            } catch (Exception x) {
            }
            return 0;
        }
    }

    private String getPipelineActivityLevel() {
        PipelineFactory pipelineFactory = PipelineFactory.getInstance();
        StringBuilder sb = new StringBuilder();
        int activityLevel = pipelineFactory.getActivityLevel();
        int errCount = pipelineFactory.getErrorFileCount();
        if (activityLevel == 0) {
            sb.append("idle.");
        } else {
            sb.append("active-" + activityLevel);
            if (errCount > 0) {
                sb.append(" errors-" + errCount);
            }
        }
        return sb.toString();
    }
}