rrdadhocgraphservlet.java

来自「opennms得相关源码 请大家看看」· Java 代码 · 共 233 行

//
// This file is part of the OpenNMS(R) Application.
//
// OpenNMS(R) is Copyright (C) 2002-2003 The OpenNMS Group, Inc.  All rights reserved.
// OpenNMS(R) is a derivative work, containing both original code, included code and modified
// code that was published under the GNU General Public License. Copyrights for modified 
// and included code are below.
//
// OpenNMS(R) is a registered trademark of The OpenNMS Group, Inc.
//
// Copyright (C) 1999-2001 Oculan Corp.  All rights reserved.
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
//
// For more information contact:
//      OpenNMS Licensing       <[e-mail]>
//      http://www.opennms.org/
//      http://www.opennms.com/
//

package org.opennms.web.graph;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.text.MessageFormat;
import java.util.Properties;

import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.opennms.core.resource.Vault;
import org.opennms.netmgt.rrd.RrdException;
import org.opennms.netmgt.rrd.RrdUtils;
import org.opennms.netmgt.utils.RrdFileConstants;
import org.opennms.web.Util;

/**
 * A servlet that creates a custom graph of network performance data using the
 * <a href="http://www.rrdtool.org/">RRDTool </a>.
 * 
 * <p>
 * This servlet executes an <em>rrdtool graph</em> command in another process,
 * piping its PNG file to standard out. The servlet then reads that PNG file and
 * returns it on the <code>ServletOutputStream</code>.
 * </p>
 * 
 * @author <A HREF="mailto:[e-mail]">Lawrence Karnowski </A>
 * @author <A HREF="http://www.opennms.org/">OpenNMS </A>
 */
public class RRDAdHocGraphServlet extends HttpServlet {
    /**
     * The working directory as specifed in the rrdtool-graph properties file.
     */
    protected File workDir;

    /**
     * The prefix for the RRDtool command (including the executable's pathname)
     * as specified in the rrdtool-graph properties file.
     */
    protected String commandPrefix;

    /**
     * The mime type of the image we will return.
     */
    protected String mimeType;

    /**
     * Holds the information specified in the rrdtool-graph properties file.
     */
    protected Properties properties;

    /**
     * Initializes this servlet by reading the rrdtool-graph properties file.
     */
    public void init() throws ServletException {
        try {
            String propertiesFilename = Vault.getHomeDir() + this.getServletConfig().getInitParameter("rrd-properties");

            this.properties = new Properties();
            this.properties.load(new FileInputStream(propertiesFilename));

            RrdUtils.graphicsInitialize();
        } catch (FileNotFoundException e) {
            throw new ServletException("Could not find configuration file", e);
        } catch (IOException e) {
            throw new ServletException("Could not load configuration file", e);
        } catch (RrdException e) {
            throw new ServletException("Could not initialize graphing system", e);
        }

        this.workDir = new File(this.properties.getProperty("command.input.dir"));
        this.commandPrefix = this.properties.getProperty("command.prefix");
        this.mimeType = this.properties.getProperty("output.mime");
    }

    /**
     * Checks the parameters passed to this servlet, and if all are okay,
     * executes the RRDTool command in another process and pipes its PNG output
     * to the <code>ServletOutputStream</code> back to the requesting web
     * browser.
     */
    public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        String rrdDir = request.getParameter("rrddir");
        String start = request.getParameter("start");
        String end = request.getParameter("end");

        if (rrdDir == null || start == null || end == null) {
            response.setContentType("image/png");
            Util.streamToStream(this.getServletContext().getResourceAsStream("/images/rrd/missingparams.png"), response.getOutputStream());
            return;
        }

        if (!RrdFileConstants.isValidRRDName(rrdDir)) {
            this.log("Illegal RRD directory: " + rrdDir);
            throw new IllegalArgumentException("Illegal RRD directory: " + rrdDir);
        }

        // begin inserted code
        String command = createAdHocCommand(request, rrdDir, start, end);

        if (command == null) {
            response.setContentType("image/png");
            Util.streamToStream(this.getServletContext().getResourceAsStream("/images/rrd/missingparams.png"), response.getOutputStream());
            return;
        }

        InputStream tempIn = null;
        ServletOutputStream out = response.getOutputStream();
        try {

            this.log("Executing RRD command in this directory: " + workDir);
            this.log(command);

            tempIn = RrdUtils.createGraph(command, workDir);

        } catch (RrdException e) {
            this.log("Read from stderr: " + e.getMessage());
            response.setContentType("image/png");
            Util.streamToStream(this.getServletContext().getResourceAsStream("/images/rrd/error.png"), out);
        }

        if (tempIn != null) {
            response.setContentType(this.mimeType);
            Util.streamToStream(tempIn, out);

            tempIn.close();
        }
        out.close();

        // end inserted code
    }

    protected String createAdHocCommand(HttpServletRequest request, String rrdDir, String start, String end) {
        String title = this.properties.getProperty("adhoc.command.title");
        String ds = this.properties.getProperty("adhoc.command.ds");
        String graphline = this.properties.getProperty("adhoc.command.graphline");

        // remember rrdtool wants the time in seconds, not milliseconds;
        // java.util.Date.getTime() returns milliseconds, so divide by 1000
        String starttime = Long.toString(Long.parseLong(start) / 1000);
        String endtime = Long.toString(Long.parseLong(end) / 1000);

        String graphtitle = request.getParameter("title");

        if (graphtitle == null) {
            return null;
        }

        StringBuffer buf = new StringBuffer();
        buf.append(this.commandPrefix);
        buf.append(" ");
        buf.append(title);

        String dsNames[] = request.getParameterValues("ds");
        String dsAggregFxns[] = request.getParameterValues("agfunction");
        String colors[] = request.getParameterValues("color");
        String dsTitles[] = request.getParameterValues("dstitle");
        String dsStyles[] = request.getParameterValues("style");

        if (dsNames == null || dsAggregFxns == null || colors == null || dsTitles == null || dsStyles == null) {
            return null;
        }

        for (int i = 0; i < dsNames.length; i++) {
            String dsAbbrev = "ds" + Integer.toString(i);

            String dsName = dsNames[i];
            String rrd = rrdDir + File.separator + dsNames[i] + RrdFileConstants.RRD_SUFFIX;
            String dsAggregFxn = dsAggregFxns[i];
            String color = colors[i];
            String dsTitle = dsTitles[i];
            String dsStyle = dsStyles[i];

            buf.append(" ");
            buf.append(MessageFormat.format(ds, new String[] { rrd, starttime, endtime, graphtitle, dsAbbrev, dsName, dsAggregFxn, dsStyle, color, dsTitle }));
        }

        for (int i = 0; i < dsNames.length; i++) {
            String dsAbbrev = "ds" + Integer.toString(i);

            String dsName = dsNames[i];
            String rrd = rrdDir + File.separator + dsNames[i] + RrdFileConstants.RRD_SUFFIX;
            String dsAggregFxn = dsAggregFxns[i];
            String color = colors[i];
            String dsTitle = dsTitles[i];
            String dsStyle = dsStyles[i];

            buf.append(" ");
            buf.append(MessageFormat.format(graphline, new String[] { rrd, starttime, endtime, graphtitle, dsAbbrev, dsName, dsAggregFxn, dsStyle, color, dsTitle }));
        }

        return MessageFormat.format(buf.toString(), new String[] { "bogus-rrd", starttime, endtime, graphtitle });
    }
}