001 //$HeadURL: https://svn.wald.intevation.org/svn/deegree/base/branches/2.3_testing/src/org/deegree/ogcwebservices/wfs/GetFeatureHandler.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.ogcwebservices.wfs;
037
038 import static org.deegree.framework.util.TimeTools.getISOFormattedTime;
039 import static org.deegree.ogcbase.ExceptionCode.INVALIDPARAMETERVALUE;
040
041 import java.util.ArrayList;
042 import java.util.List;
043 import java.util.concurrent.Callable;
044 import java.util.concurrent.CancellationException;
045
046 import org.deegree.datatypes.QualifiedName;
047 import org.deegree.framework.concurrent.ExecutionFinishedEvent;
048 import org.deegree.framework.concurrent.Executor;
049 import org.deegree.framework.log.ILogger;
050 import org.deegree.framework.log.LoggerFactory;
051 import org.deegree.i18n.Messages;
052 import org.deegree.io.datastore.Datastore;
053 import org.deegree.io.datastore.PropertyPathResolvingException;
054 import org.deegree.io.datastore.schema.MappedFeatureType;
055 import org.deegree.model.feature.FeatureCollection;
056 import org.deegree.model.feature.GMLFeatureAdapter;
057 import org.deegree.model.feature.GMLFeatureCollectionDocument;
058 import org.deegree.ogcwebservices.OGCWebServiceException;
059 import org.deegree.ogcwebservices.wfs.capabilities.WFSCapabilities;
060 import org.deegree.ogcwebservices.wfs.capabilities.WFSFeatureType;
061 import org.deegree.ogcwebservices.wfs.capabilities.WFSOperationsMetadata;
062 import org.deegree.ogcwebservices.wfs.configuration.WFSConfiguration;
063 import org.deegree.ogcwebservices.wfs.operation.FeatureResult;
064 import org.deegree.ogcwebservices.wfs.operation.GetFeature;
065 import org.deegree.ogcwebservices.wfs.operation.Query;
066 import org.deegree.ogcwebservices.wfs.operation.GetFeature.RESULT_TYPE;
067 import org.deegree.owscommon.OWSDomainType;
068
069 /**
070 * Handles {@link GetFeature} requests to the {@link WFService}. Since a {@link GetFeature} request may contain more
071 * than one {@link Query}, each {@link Query} is delegated to an own thread.
072 * <p>
073 * The results of all threads are collected and merged before they are returned to the calling {@link WFService} as a
074 * single {@link FeatureCollection}.
075 *
076 * @author <a href="mailto:poth@lat-lon.de">Andreas Poth</a>
077 * @author <a href="mailto:schneider@lat-lon.de">Markus Schneider</a>
078 * @author last edited by: $Author: mschneider $
079 *
080 * @version $Revision: 18195 $, $Date: 2009-06-18 17:55:39 +0200 (Do, 18. Jun 2009) $
081 */
082 class GetFeatureHandler {
083
084 private static final ILogger LOG = LoggerFactory.getLogger( GetFeatureHandler.class );
085
086 // upper limit for timeout (overrides WFS configuration)
087 private static long MAX_TIMEOUT_MILLIS = 60 * 60 * 1000;
088
089 private WFService wfs;
090
091 private int maxFeatures = -1;
092
093 /**
094 * Creates a new instance of <code>GetFeatureHandler</code>. Only called by the associated {@link WFService} (once).
095 *
096 * @param wfs
097 * associated WFService
098 */
099 GetFeatureHandler( WFService wfs ) {
100 this.wfs = wfs;
101 WFSCapabilities capa = wfs.getCapabilities();
102 WFSOperationsMetadata md = (WFSOperationsMetadata) capa.getOperationsMetadata();
103 OWSDomainType[] dt = md.getConstraints();
104 for ( int i = 0; i < dt.length; i++ ) {
105 if ( dt[i].getName().equals( "DefaultMaxFeatures" ) ) {
106 try {
107 String tmp = dt[i].getValues()[0];
108 this.maxFeatures = Integer.parseInt( tmp );
109 } catch ( Exception e ) {
110 // e.printStackTrace();
111 }
112 break;
113 }
114 }
115 LOG.logDebug( "default maxFeatures " + this.maxFeatures );
116 }
117
118 /**
119 * Handles a {@link GetFeature} request by delegating the contained {@link Query} objects to different threads.
120 * <p>
121 * If at least one query fails an exception will be thrown and all running threads will be stopped.
122 *
123 * @param getFeature
124 * @return result of the request
125 * @throws OGCWebServiceException
126 */
127 FeatureResult handleRequest( GetFeature getFeature )
128 throws OGCWebServiceException {
129
130 WFSConfiguration conf = (WFSConfiguration) wfs.getCapabilities();
131
132 if ( getFeature.getMaxFeatures() > this.maxFeatures || getFeature.getMaxFeatures() <= 0 ) {
133 getFeature.setMaxFeatures( this.maxFeatures );
134 }
135
136 LOG.logDebug( "maxFeatures " + getFeature.getMaxFeatures() );
137
138 Query[] queries = getFeature.getQuery();
139 List<Callable<FeatureCollection>> queryTasks = new ArrayList<Callable<FeatureCollection>>( queries.length );
140
141 for ( Query query : queries ) {
142
143 if ( conf.getDeegreeParams().checkUTMZones() ) {
144 query.performBBoxTest();
145 }
146
147 query.deleteBBoxTest();
148
149 QualifiedName[] ftNames = query.getTypeNames();
150 MappedFeatureType[] requestedFts = new MappedFeatureType[ftNames.length];
151 Datastore ds = null;
152
153 for ( int i = 0; i < ftNames.length; i++ ) {
154 QualifiedName ftName = ftNames[i];
155 MappedFeatureType ft = this.wfs.getMappedFeatureType( ftName );
156
157 if ( ft == null ) {
158 String msg = Messages.getMessage( "WFS_FEATURE_TYPE_UNKNOWN", ftName );
159 throw new OGCWebServiceException( this.getClass().getName(), msg );
160 }
161 if ( ft.isAbstract() ) {
162 String msg = Messages.getMessage( "WFS_FEATURE_TYPE_ABSTRACT", ftName );
163 throw new OGCWebServiceException( this.getClass().getName(), msg );
164 }
165 if ( !ft.isVisible() ) {
166 String msg = Messages.getMessage( "WFS_FEATURE_TYPE_INVISIBLE", ftName );
167 throw new OGCWebServiceException( this.getClass().getName(), msg );
168 }
169 Datastore dsForFt = ft.getGMLSchema().getDatastore();
170 if ( ds != null ) {
171 if ( ds != dsForFt ) {
172 String msg = Messages.getMessage( "WFS_QUERY_JOIN_OVER_DIFFERENT_DS" );
173 throw new OGCWebServiceException( this.getClass().getName(), msg );
174 }
175 } else {
176 ds = dsForFt;
177 }
178 requestedFts[i] = ft;
179 }
180
181 // TODO what about joins here?
182 String srsName = query.getSrsName();
183 if ( srsName != null ) {
184 WFSFeatureType wfsFT = this.wfs.getCapabilities().getFeatureTypeList().getFeatureType( ftNames[0] );
185
186 if ( !( wfsFT.supportsSrs( srsName ) ) ) {
187 String msg = Messages.getMessage( "WFS_FEATURE_TYPE_SRS_UNSUPPORTED", ftNames[0], srsName );
188 throw new OGCWebServiceException( this.getClass().getName(), msg );
189 }
190 }
191
192 QueryTask task = new QueryTask( ds, query, requestedFts );
193 queryTasks.add( task );
194 }
195
196 long timeout = conf.getDeegreeParams().getRequestTimeLimit() * 1000;
197 if ( timeout > MAX_TIMEOUT_MILLIS ) {
198 // limit max timeout
199 timeout = MAX_TIMEOUT_MILLIS;
200 }
201
202 List<ExecutionFinishedEvent<FeatureCollection>> finishedEvents = null;
203 try {
204 finishedEvents = Executor.getInstance().performSynchronously( queryTasks, timeout );
205 } catch ( InterruptedException e ) {
206 String msg = "Exception occured while waiting for the GetFeature results: " + e.getMessage();
207 throw new OGCWebServiceException( this.getClass().getName(), msg );
208 }
209
210 // use id of the request as id of the result feature collection
211 // to allow identification of the original request that produced
212 // the feature collection
213 FeatureCollection fc = null;
214 if ( getFeature.getResultType() == RESULT_TYPE.RESULTS ) {
215 fc = mergeResults( getFeature.getId(), finishedEvents );
216 } else {
217 fc = mergeHits( getFeature.getId(), finishedEvents );
218 }
219
220 // TODO this is not a good solution
221 // I think it can happen if more than one feature type is requested
222 while ( getFeature.getMaxFeatures() > 0 && fc.size() > getFeature.getMaxFeatures() ) {
223 fc.remove( fc.size() - 1 );
224 }
225
226 if ( LOG.isDebug() ) {
227 try {
228 GMLFeatureAdapter ada = new GMLFeatureAdapter( false );
229 GMLFeatureCollectionDocument doc = ada.export( fc );
230 LOG.logDebugXMLFile( "GetFeatureHandler_result", doc );
231 } catch ( Exception e ) {
232 LOG.logError( e.getMessage(), e );
233 }
234 }
235
236 FeatureResult fr = new FeatureResult( getFeature, fc );
237 return fr;
238 }
239
240 /**
241 * Merges the results of the request subparts into one feature collection.
242 *
243 * @param fcid
244 * id of the new (result) feature collection
245 * @param finishedEvents
246 * @return feature collection containing all features from all responses
247 * @throws OGCWebServiceException
248 */
249 private FeatureCollection mergeResults( String fcid, List<ExecutionFinishedEvent<FeatureCollection>> finishedEvents )
250 throws OGCWebServiceException {
251
252 FeatureCollection result = null;
253
254 try {
255 for ( ExecutionFinishedEvent<FeatureCollection> event : finishedEvents ) {
256 if ( result == null ) {
257 result = event.getResult();
258 } else {
259 result.addAllUncontained( event.getResult() );
260 }
261 }
262
263 if ( result == null ) {
264 return result;
265 }
266 } catch ( CancellationException e ) {
267 LOG.logError( e.getMessage(), e );
268 String msg = Messages.getMessage( "WFS_GET_FEATURE_TIMEOUT", e.getMessage() );
269 throw new OGCWebServiceException( this.getClass().getName(), msg );
270 } catch ( PropertyPathResolvingException e ) {
271 LOG.logDebug( "Stack trace", e );
272 throw new OGCWebServiceException( e.getLocalizedMessage(), INVALIDPARAMETERVALUE );
273 } catch ( Throwable t ) {
274 LOG.logError( t.getMessage(), t );
275 String msg = Messages.getMessage( "WFS_GET_FEATURE_BACKEND", t.getMessage() );
276 throw new OGCWebServiceException( this.getClass().getName(), msg );
277 }
278
279 result.setId( fcid );
280 result.setAttribute( "numberOfFeatures", "" + result.size() );
281 return result;
282 }
283
284 /**
285 * Merges the results of the request subparts into one feature collection.
286 * <p>
287 * This method is used if only the HITS have been requested, i.e. the number of features.
288 *
289 * TODO: Do this a better way (maybe change feature model).
290 *
291 * @param fcid
292 * id of the new (result) feature collection
293 * @param finishedEvents
294 * @return empty feature collection with "numberOfFeatures" attribute
295 * @throws OGCWebServiceException
296 */
297 private FeatureCollection mergeHits( String fcid, List<ExecutionFinishedEvent<FeatureCollection>> finishedEvents )
298 throws OGCWebServiceException {
299
300 FeatureCollection result = null;
301 int numberOfFeatures = 0;
302
303 try {
304 for ( ExecutionFinishedEvent<FeatureCollection> event : finishedEvents ) {
305 FeatureCollection fc = event.getResult();
306 try {
307 numberOfFeatures += Integer.parseInt( ( fc.getAttribute( "numberOfFeatures" ) ) );
308 } catch ( NumberFormatException e ) {
309 String msg = "Internal error. Could not parse 'numberOfFeatures' attribute "
310 + "of sub-result as an integer value.";
311 throw new OGCWebServiceException( this.getClass().getName(), msg );
312 }
313 if ( result == null ) {
314 result = fc;
315 } else {
316 result.addAllUncontained( fc );
317 }
318 }
319
320 if ( result == null ) {
321 return result;
322 }
323 } catch ( CancellationException e ) {
324 String msg = Messages.getMessage( "WFS_GET_FEATURE_TIMEOUT" );
325 LOG.logError( msg, e );
326 throw new OGCWebServiceException( this.getClass().getName(), msg );
327 } catch ( Throwable t ) {
328 String msg = Messages.getMessage( "WFS_GET_FEATURE_BACKEND", t.getMessage() );
329 LOG.logError( msg, t );
330 throw new OGCWebServiceException( this.getClass().getName(), msg );
331 }
332
333 result.setId( fcid );
334 result.setAttribute( "numberOfFeatures", "" + numberOfFeatures );
335 result.setAttribute( "timeStamp", getISOFormattedTime() );
336 return result;
337 }
338
339 // ///////////////////////////////////////////////////////////////////////////
340 // inner classes
341 // ///////////////////////////////////////////////////////////////////////////
342
343 /**
344 * Inner class for performing queries on a datastore.
345 */
346 private class QueryTask implements Callable<FeatureCollection> {
347
348 private Datastore ds;
349
350 private Query query;
351
352 private MappedFeatureType[] fts;
353
354 QueryTask( Datastore ds, Query query, MappedFeatureType[] fts ) {
355 this.ds = ds;
356 this.query = query;
357 this.fts = fts;
358 }
359
360 /**
361 * Performs the associated {@link Query} and returns the result.
362 *
363 * @return resulting feature collection
364 * @throws Exception
365 */
366 public FeatureCollection call()
367 throws Exception {
368 FeatureCollection result = this.ds.performQuery( query, fts );
369 return result;
370 }
371 }
372 }