    001    //$HeadURL: https://svn.wald.intevation.org/svn/deegree/base/branches/2.4_testing/src/org/deegree/enterprise/servlet/SimpleProxyServlet.java $
    002    /*----------------------------------------------------------------------------
    003     This file is part of deegree, http://deegree.org/
    004     Copyright (C) 2001-2009 by:
    005     Department of Geography, University of Bonn
    006     and
    007     lat/lon GmbH
    008
    009     This library is free software; you can redistribute it and/or modify it under
    010     the terms of the GNU Lesser General Public License as published by the Free
    011     Software Foundation; either version 2.1 of the License, or (at your option)
    012     any later version.
    013     This library is distributed in the hope that it will be useful, but WITHOUT
    014     ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
    015     FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
    016     details.
    017     You should have received a copy of the GNU Lesser General Public License
    018     along with this library; if not, write to the Free Software Foundation, Inc.,
    019     59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
    020
    021     Contact information:
    022
    023     lat/lon GmbH
    024     Aennchenstr. 19, 53177 Bonn
    025     Germany
    026     http://lat-lon.de/
    027
    028     Department of Geography, University of Bonn
    029     Prof. Dr. Klaus Greve
    030     Postfach 1147, 53001 Bonn
    031     Germany
    032     http://www.geographie.uni-bonn.de/deegree/
    033
    034     e-mail: info@deegree.org
    035     ----------------------------------------------------------------------------*/
    036    package org.deegree.enterprise.servlet;
    037
    038    import java.io.IOException;
    039    import java.io.InputStream;
    040    import java.io.OutputStream;
    041    import java.net.URL;
    042    import java.net.URLConnection;
    043    import java.util.Enumeration;
    044    import java.util.HashMap;
    045    import java.util.Map;
    046
    047    import javax.servlet.ServletException;
    048    import javax.servlet.http.HttpServlet;
    049    import javax.servlet.http.HttpServletRequest;
    050    import javax.servlet.http.HttpServletResponse;
    051
    052    import org.apache.commons.httpclient.HttpClient;
    053    import org.apache.commons.httpclient.methods.InputStreamRequestEntity;
    054    import org.apache.commons.httpclient.methods.PostMethod;
    055    import org.deegree.enterprise.WebUtils;
    056    import org.deegree.framework.log.ILogger;
    057    import org.deegree.framework.log.LoggerFactory;
    058    import org.deegree.framework.util.CharsetUtils;
    059    import org.deegree.framework.util.KVP2Map;
    060    import org.deegree.framework.util.StringTools;
    061    import org.deegree.i18n.Messages;
    062    import org.deegree.ogcwebservices.OGCRequestFactory;
    063    import org.deegree.ogcwebservices.OGCWebServiceException;
    064    import org.deegree.ogcwebservices.OGCWebServiceRequest;
    065
    066    /**
    067     * simple proxy servlet The servlet is intended to run in its own context combined with ServletFilter (e.g.
    068     * OWSProxyServletFilter ) to filter out invalid requests/responses
    069     *
    070     * @version $Revision: 20309 $
    071     * @author <a href="mailto:poth@lat-lon.de">Andreas Poth </a>
    072     * @author last edited by: $Author: aschmitz $
    073     *
    074     * @version 1.0. $Revision: 20309 $, $Date: 2009-10-22 16:24:01 +0200 (Do, 22. Okt 2009) $
    075     *
    076     * @since 1.1
    077     */
    078    public class SimpleProxyServlet extends HttpServlet {
    079
    080        private ILogger LOG = LoggerFactory.getLogger( SimpleProxyServlet.class );
    081
    082        private static final long serialVersionUID = 3086952074808203858L;
    083
    084        private Map<String, String> host = null;
    085
    086        private boolean removeCredentials = false;
    087
    088        /**
    089         * @see javax.servlet.GenericServlet#init()
    090         */
    091        @Override
    092        public void init()
    093                                throws ServletException {
    094            super.init();
    095            host = new HashMap<String, String>();
    096            Enumeration<?> enu = getInitParameterNames();
    097            while ( enu.hasMoreElements() ) {
    098                String pn = (String) enu.nextElement();
    099                if ( pn.toLowerCase().equals( "removecredentials" ) ) {
    100                    removeCredentials = getInitParameter( pn ).equalsIgnoreCase( "true" );
    101                    continue;
    102                }
    103                String[] tmp = StringTools.toArray( pn, ":", false );
    104                String hostAddr = this.getInitParameter( pn );
    105                host.put( tmp[0], hostAddr );
    106            }
    107        }
    108
    109        /**
    110         * @see javax.servlet.http.HttpServlet#doGet(javax.servlet.http.HttpServletRequest,
    111         *      javax.servlet.http.HttpServletResponse)
    112         */
    113        @Override
    114        protected void doGet( HttpServletRequest request, HttpServletResponse response )
    115                                throws ServletException, IOException {
    116            InputStream is = null;
    117            OutputStream os = null;
    118            try {
    119                String query = request.getQueryString();
    120                Map<String, String> map = KVP2Map.toMap( query );
    121                if ( removeCredentials ) {
    122                    map.remove( "USER" );
    123                    map.remove( "PASSWORD" );
    124                    map.remove( "SESSIONID" );
    125                    query = "";
    126                    for ( String key : map.keySet() ) {
    127                        query += key + "=" + map.get( key ) + "&";
    128                    }
    129                    query = query.substring( 0, query.length() - 1 );
    130                }
    131                String service = getService( map );
    132                String hostAddr = host.get( service );
    133                String req = hostAddr + "?" + query;
    134                URL url = new URL( req );
    135                LOG.logDebug( "forward URL: " + url );
    136
    137                URLConnection con = url.openConnection();
    138                con.setDoInput( true );
    139                con.setDoOutput( false );
    140                is = con.getInputStream();
    141                response.setContentType( con.getContentType() );
    142                response.setCharacterEncoding( con.getContentEncoding() );
    143                os = response.getOutputStream();
    144                int read = 0;
    145                byte[] buf = new byte[16384];
    146                if ( LOG.getLevel() == ILogger.LOG_DEBUG ) {
    147                    while ( ( read = is.read( buf ) ) > -1 ) {
    148                        os.write( buf, 0, read );
    149                        LOG.logDebug( new String( buf, 0, read, con.getContentEncoding() ) );
    150                    }
    151                } else {
    152                    while ( ( read = is.read( buf ) ) > -1 ) {
    153                        os.write( buf, 0, read );
    154                    }
    155                }
    156
    157            } catch ( Exception e ) {
    158                e.printStackTrace();
    159                response.setContentType( "text/plain; charset=" + CharsetUtils.getSystemCharset() );
    160                os.write( StringTools.stackTraceToString( e ).getBytes() );
    161            } finally {
    162                try {
    163                    is.close();
    164                } catch ( Exception e ) {
    165                    // try to do what ?
    166                }
    167                try {
    168                    os.close();
    169                } catch ( Exception e ) {
    170                    // try to do what ?
    171                }
    172            }
    173        }
    174
    175        /**
    176         * @see javax.servlet.http.HttpServlet#doPost(javax.servlet.http.HttpServletRequest,
    177         *      javax.servlet.http.HttpServletResponse)
    178         */
    179        @Override
    180        protected void doPost( HttpServletRequest origReq, HttpServletResponse response )
    181                                throws ServletException, IOException {
    182            // wrap request to enable access of the requests InputStream more
    183            // than one time
    184            ServletRequestWrapper request = new ServletRequestWrapper( origReq );
    185            OutputStream os = null;
    186            try {
    187                if ( LOG.getLevel() == ILogger.LOG_DEBUG ) {
    188                    // because this is an expensive operation it just will
    189                    // performed if debug level is set too DEBUG
    190                    InputStream reqIs = request.getInputStream();
    191                    StringBuffer sb = new StringBuffer( 10000 );
    192                    int c = 0;
    193                    while ( ( c = reqIs.read() ) > -1 ) {
    194                        sb.append( (char) c );
    195                    }
    196                    reqIs.close();
    197                    LOG.logDebug( "Request: " + sb );
    198                }
    199                OGCWebServiceRequest req = OGCRequestFactory.create( request );
    200
    201                String hostAddr = host.get( req.getServiceName() );
    202                LOG.logDebug( "forward URL: " + hostAddr );
    203                if ( hostAddr == null ) {
    204                    throw new Exception( Messages.getMessage( "PROXY_SERVLET_UNDEFINED_HOST", req.getServiceName() ) );
    205                }
    206
    207                // determine charset for setting request content type
    208                // use system charset if no charset can be determined
    209                // from incoming request
    210                String charset = origReq.getCharacterEncoding();
    211                LOG.logDebug( "request character encoding: ", charset );
    212                if ( charset == null ) {
    213                    charset = CharsetUtils.getSystemCharset();
    214                    LOG.logDebug( "use sytem character encoding: ", charset );
    215                }
    216
    217                HttpClient client = new HttpClient();
    218                client = WebUtils.enableProxyUsage( client, new URL( hostAddr ) );
    219                PostMethod post = new PostMethod( hostAddr );
    220                post.setRequestHeader( "Content-type", "text/xml; charset=" + charset );
    221                post.setRequestEntity( new InputStreamRequestEntity( request.getInputStream() ) );
    222                client.executeMethod( post );
    223
    224                LOG.logDebug( "Content-type: ", post.getResponseHeader( "Content-type" ) );
    225
    226                os = response.getOutputStream();
    227                os.write( post.getResponseBody() );
    228            } catch ( Exception e ) {
    229                e.printStackTrace();
    230                response.setContentType( "text/plain; charset=" + CharsetUtils.getSystemCharset() );
    231                os.write( StringTools.stackTraceToString( e ).getBytes() );
    232            } finally {
    233                try {
    234                    os.close();
    235                } catch ( Exception e ) {
    236                    e.printStackTrace();
    237                }
    238            }
    239        }
    240
    241        /**
    242         * @return the name of the service that is targeted by the passed KVP encoded request
    243         *
    244         * @param map
    245         * @throws Exception
    246         */
    247        private String getService( Map<String, String> map )
    248                                throws Exception {
    249            String service = null;
    250            String req = map.get( "REQUEST" );
    251            if ( "WMS".equals( map.get( "SERVICE" ) ) || req.equals( "GetMap" ) || req.equals( "GetFeatureInfo" )
    252                 || req.equals( "GetLegendGraphic" ) ) {
    253                service = "WMS";
    254            } else if ( "WFS".equals( map.get( "SERVICE" ) ) || req.equals( "DescribeFeatureType" )
    255                        || req.equals( "GetFeature" ) ) {
    256                service = "WFS";
    257            } else if ( "WCS".equals( map.get( "SERVICE" ) ) || req.equals( "GetCoverage" )
    258                        || req.equals( "DescribeCoverage" ) ) {
    259                service = "WCS";
    260            } else if ( "CSW".equals( map.get( "SERVICE" ) ) || req.equals( "GetRecords" ) || req.equals( "GetRecordById" )
    261                        || req.equals( "Harvest" ) || req.equals( "DescribeRecord" ) ) {
    262                service = "CSW";
    263            } else {
    264                throw new OGCWebServiceException( "unknown service/request: " + map.get( "SERVICE" ) );
    265            }
    266            return service;
    267        }
    268
    269    }