001 //$HeadURL: svn+ssh://rbezema@svn.wald.intevation.org/deegree/base/branches/2.2_testing/src/org/deegree/io/datastore/wfs/CascadingWFSDatastore.java $
002 /*---------------- FILE HEADER ------------------------------------------
003
004 This file is part of deegree.
005 Copyright (C) 2001-2008 by:
006 EXSE, Department of Geography, University of Bonn
007 http://www.giub.uni-bonn.de/deegree/
008 lat/lon GmbH
009 http://www.lat-lon.de
010
011 This library is free software; you can redistribute it and/or
012 modify it under the terms of the GNU Lesser General Public
013 License as published by the Free Software Foundation; either
014 version 2.1 of the License, or (at your option) any later version.
015
016 This library is distributed in the hope that it will be useful,
017 but WITHOUT ANY WARRANTY; without even the implied warranty of
018 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
019 Lesser General Public License for more details.
020
021 You should have received a copy of the GNU Lesser General Public
022 License along with this library; if not, write to the Free Software
023 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
024
025 Contact:
026
027 Andreas Poth
028 lat/lon GmbH
029 Aennchenstr. 19
030 53177 Bonn
031 Germany
032 E-Mail: poth@lat-lon.de
033
034 Prof. Dr. Klaus Greve
035 Department of Geography
036 University of Bonn
037 Meckenheimer Allee 166
038 53115 Bonn
039 Germany
040 E-Mail: greve@giub.uni-bonn.de
041
042 ---------------------------------------------------------------------------*/
043 package org.deegree.io.datastore.wfs;
044
045 import java.io.ByteArrayOutputStream;
046 import java.io.IOException;
047 import java.io.InputStream;
048 import java.net.MalformedURLException;
049 import java.net.URL;
050 import java.util.ArrayList;
051 import java.util.HashMap;
052 import java.util.List;
053 import java.util.Map;
054 import java.util.concurrent.Callable;
055 import java.util.concurrent.CancellationException;
056
057 import javax.xml.transform.TransformerException;
058
059 import org.apache.commons.httpclient.HttpClient;
060 import org.apache.commons.httpclient.methods.PostMethod;
061 import org.apache.commons.httpclient.methods.StringRequestEntity;
062 import org.deegree.datatypes.QualifiedName;
063 import org.deegree.enterprise.WebUtils;
064 import org.deegree.framework.concurrent.ExecutionFinishedEvent;
065 import org.deegree.framework.concurrent.Executor;
066 import org.deegree.framework.log.ILogger;
067 import org.deegree.framework.log.LoggerFactory;
068 import org.deegree.framework.util.CharsetUtils;
069 import org.deegree.framework.xml.XMLFragment;
070 import org.deegree.framework.xml.XMLParsingException;
071 import org.deegree.framework.xml.XSLTDocument;
072 import org.deegree.i18n.Messages;
073 import org.deegree.io.datastore.Datastore;
074 import org.deegree.io.datastore.DatastoreException;
075 import org.deegree.io.datastore.DatastoreTransaction;
076 import org.deegree.io.datastore.schema.MappedFeatureType;
077 import org.deegree.model.crs.UnknownCRSException;
078 import org.deegree.model.feature.FeatureCollection;
079 import org.deegree.model.feature.FeatureFactory;
080 import org.deegree.model.feature.GMLFeatureCollectionDocument;
081 import org.deegree.ogcwebservices.OGCWebServiceException;
082 import org.deegree.ogcwebservices.OWSUtils;
083 import org.deegree.ogcwebservices.getcapabilities.InvalidCapabilitiesException;
084 import org.deegree.ogcwebservices.wfs.XMLFactory;
085 import org.deegree.ogcwebservices.wfs.capabilities.WFSCapabilities;
086 import org.deegree.ogcwebservices.wfs.capabilities.WFSCapabilitiesDocument;
087 import org.deegree.ogcwebservices.wfs.operation.GetFeature;
088 import org.deegree.ogcwebservices.wfs.operation.Query;
089 import org.deegree.ogcwebservices.wfs.operation.GetFeature.RESULT_TYPE;
090 import org.xml.sax.SAXException;
091
092 /**
093 *
094 *
095 *
096 * @author <a href="mailto:poth@lat-lon.de">Andreas Poth</a>
097 * @author last edited by: $Author: apoth $
098 *
099 * @version $Revision: 9342 $, $Date: 2007-12-27 13:32:57 +0100 (Do, 27 Dez 2007) $
100 */
101 public class CascadingWFSDatastore extends Datastore {
102
103 private ILogger LOG = LoggerFactory.getLogger( CascadingWFSDatastore.class );
104
105 private static Map<URL, WFSCapabilities> wfsCapabilities;
106 static {
107 if ( wfsCapabilities == null ) {
108 wfsCapabilities = new HashMap<URL, WFSCapabilities>();
109 }
110 }
111
112 @Override
113 public CascadingWFSAnnotationDocument getAnnotationParser() {
114 return new CascadingWFSAnnotationDocument();
115 }
116
117 @Override
118 public void close()
119 throws DatastoreException {
120 }
121
122 @Override
123 public FeatureCollection performQuery( Query query, MappedFeatureType[] rootFts, DatastoreTransaction context )
124 throws DatastoreException, UnknownCRSException {
125 return performQuery( query, rootFts );
126 }
127
128 @Override
129 public FeatureCollection performQuery( Query query, MappedFeatureType[] rootFts )
130 throws DatastoreException, UnknownCRSException {
131
132 GetFeature getFeature = GetFeature.create( "1.1.0", "ID", RESULT_TYPE.RESULTS, "text/xml; subtype=gml/3.1.1",
133 "", query.getMaxFeatures(), query.getStartPosition(), -1, -1,
134 new Query[] { query } );
135 XMLFragment gfXML = null;
136 try {
137 gfXML = XMLFactory.export( getFeature );
138 } catch ( IOException e ) {
139 LOG.logError( e.getMessage(), e );
140 throw new DatastoreException( e.getMessage() );
141 } catch ( XMLParsingException e ) {
142 LOG.logError( e.getMessage(), e );
143 throw new DatastoreException( e.getMessage() );
144 }
145
146 // get URL that is target of a GetFeature request
147 CascadingWFSDatastoreConfiguration config = (CascadingWFSDatastoreConfiguration) this.getConfiguration();
148 WFSDescription[] wfs = config.getWFSDescription();
149 List<Callable<FeatureCollection>> queryTasks = new ArrayList<Callable<FeatureCollection>>( wfs.length );
150 int timeout = 0;
151 for ( int i = 0; i < wfs.length; i++ ) {
152 QueryTask task = new QueryTask( gfXML, wfs[i] );
153 queryTasks.add( task );
154 timeout += wfs[i].getTimeout();
155 }
156
157 List<ExecutionFinishedEvent<FeatureCollection>> finishedEvents = null;
158 try {
159 finishedEvents = Executor.getInstance().performSynchronously( queryTasks, timeout );
160 } catch ( InterruptedException e ) {
161 LOG.logError( e.getMessage(), e );
162 throw new DatastoreException( Messages.getMessage( "WFS_CASCDS_PERFORM_GF" ), e );
163 }
164
165 return mergeResults( getFeature.getId(), finishedEvents );
166 }
167
168 /**
169 * Merges the results of the request subparts into one feature collection.
170 *
171 * @param fcid
172 * id of the new (result) feature collection
173 * @param finishedEvents
174 * @return feature collection containing all features from all responses
175 * @throws OGCWebServiceException
176 */
177 private FeatureCollection mergeResults( String fcid, List<ExecutionFinishedEvent<FeatureCollection>> finishedEvents )
178 throws DatastoreException {
179
180 FeatureCollection result = null;
181
182 try {
183 for ( ExecutionFinishedEvent<FeatureCollection> event : finishedEvents ) {
184 if ( result == null ) {
185 result = event.getResult();
186 } else {
187 result.addAll( event.getResult() );
188 }
189 }
190 } catch ( CancellationException e ) {
191 LOG.logError( e.getMessage(), e );
192 String msg = Messages.getMessage( "WFS_GET_FEATURE_TIMEOUT", e.getMessage() );
193 throw new DatastoreException( msg, e );
194 } catch ( Throwable t ) {
195 LOG.logError( t.getMessage(), t );
196 String msg = Messages.getMessage( "WFS_GET_FEATURE_BACKEND", t.getMessage() );
197 throw new DatastoreException( msg, t );
198 }
199
200 result.setId( fcid );
201 result.setAttribute( "numberOfFeatures", "" + result.size() );
202 return result;
203 }
204
205 private WFSCapabilities getWFSCapabilities( URL url )
206 throws DatastoreException {
207 String href = OWSUtils.validateHTTPGetBaseURL( url.toExternalForm() );
208 href = href + "request=GetCapabilities&version=1.1.0&service=WFS";
209
210 LOG.logDebug( "requested capabilities: ", href );
211
212 try {
213 url = new URL( href );
214 } catch ( MalformedURLException e1 ) {
215 e1.printStackTrace();
216 }
217
218 WFSCapabilities caps = wfsCapabilities.get( url );
219 if ( caps == null ) {
220 // access capabilities if not already has been loaded
221 WFSCapabilitiesDocument cd = new WFSCapabilitiesDocument();
222 try {
223 cd.load( url );
224 } catch ( IOException e ) {
225 LOG.logError( e.getMessage(), e );
226 throw new DatastoreException( e.getMessage() );
227 } catch ( SAXException e ) {
228 LOG.logError( e.getMessage(), e );
229 throw new DatastoreException( e.getMessage() );
230 }
231 try {
232 caps = (WFSCapabilities) cd.parseCapabilities();
233 } catch ( InvalidCapabilitiesException e ) {
234 LOG.logError( e.getMessage(), e );
235 throw new DatastoreException( e.getMessage() );
236 }
237 wfsCapabilities.put( url, caps );
238 }
239 return caps;
240 }
241
242 // ///////////////////////////////////////////////////////////////////////////
243 // inner classes
244 // ///////////////////////////////////////////////////////////////////////////
245
246 /**
247 * Inner class for performing queries on a datastore.
248 */
249 private class QueryTask implements Callable<FeatureCollection> {
250
251 private XMLFragment getFeature;
252
253 private WFSDescription wfs;
254
255 /**
256 *
257 * @param getFeature
258 * @param wfs
259 */
260 QueryTask( XMLFragment getFeature, WFSDescription wfs ) {
261 this.getFeature = getFeature;
262 this.wfs = wfs;
263 }
264
265 /**
266 * Performs the associated {@link Query} and returns the result.
267 *
268 * @return resulting feature collection
269 * @throws Exception
270 */
271 public FeatureCollection call()
272 throws Exception {
273
274 URL url = OWSUtils.getHTTPPostOperationURL( getWFSCapabilities( wfs.getUrl() ), GetFeature.class );
275
276 // filter request if necessary
277 XSLTDocument inFilter = wfs.getInFilter();
278 if ( inFilter != null ) {
279 try {
280 getFeature = inFilter.transform( getFeature );
281 } catch ( TransformerException e ) {
282 LOG.logError( e.getMessage(), e );
283 throw new DatastoreException( e.getMessage() );
284 }
285 }
286
287 if ( isFeatureTypeSupported( getFeature, wfs.getUrl() ) ) {
288
289 InputStream is = null;
290 FeatureCollection fc = null;
291 try {
292 // perform GetFeature request against cascaded WFS
293 HttpClient client = new HttpClient();
294 client = WebUtils.enableProxyUsage( client, url );
295 client.getHttpConnectionManager().getParams().setSoTimeout( wfs.getTimeout() );
296 PostMethod post = new PostMethod( url.toExternalForm() );
297 StringRequestEntity se = new StringRequestEntity( getFeature.getAsString(), "text/xml",
298 CharsetUtils.getSystemCharset() );
299 post.setRequestEntity( se );
300 client.executeMethod( post );
301 is = post.getResponseBodyAsStream();
302 } catch ( Exception e ) {
303 throw new DatastoreException( Messages.getMessage( "DATASTORE_WFS_ACCESS", url ) );
304 }
305
306 // read result as GMLFeatureColllection
307 GMLFeatureCollectionDocument fcd = new GMLFeatureCollectionDocument( true );
308 try {
309 fcd.load( is, url.toExternalForm() );
310 } catch ( Exception e ) {
311 if ( LOG.getLevel() == ILogger.LOG_DEBUG ) {
312 ByteArrayOutputStream bos = new ByteArrayOutputStream( 50000 );
313 int c = 0;
314 while ( c > -1 ) {
315 c = is.read();
316 bos.write( c );
317 }
318 byte[] b = bos.toByteArray();
319 bos.close();
320 System.out.println( new String( b ) );
321 }
322 LOG.logError( e.getMessage(), e );
323 throw new DatastoreException( e.getMessage() );
324 } finally {
325 try {
326 is.close();
327 } catch ( IOException shouldNeverHappen ) {
328 }
329 }
330
331 // filter result if necessary
332 XSLTDocument outFilter = wfs.getOutFilter();
333 if ( outFilter != null ) {
334 try {
335 XMLFragment xml = outFilter.transform( fcd );
336 fcd = new GMLFeatureCollectionDocument();
337 fcd.setRootElement( xml.getRootElement() );
338 } catch ( TransformerException e ) {
339 LOG.logError( e.getMessage(), e );
340 throw new DatastoreException( e.getMessage() );
341 }
342 }
343 try {
344 fc = fcd.parse();
345 } catch ( XMLParsingException e ) {
346 LOG.logError( e.getMessage(), e );
347 throw new DatastoreException( e.getMessage() );
348 }
349
350 return fc;
351 } else {
352 return FeatureFactory.createFeatureCollection( "ID", 1 );
353 }
354 }
355
356 /**
357 * returns true if the WFS reachable through the passed URL supports all feature types
358 * targeted by the passed GetFeature request.
359 *
360 * @param getFeature
361 * @param url
362 * @return
363 * @throws OGCWebServiceException
364 * @throws DatastoreException
365 */
366 private boolean isFeatureTypeSupported( XMLFragment getFeature, URL url )
367 throws OGCWebServiceException, DatastoreException {
368
369 WFSCapabilities caps = getWFSCapabilities( url );
370
371 GetFeature gf = GetFeature.create( "ID" + System.currentTimeMillis(), getFeature.getRootElement() );
372 Query[] queries = gf.getQuery();
373 for ( int i = 0; i < queries.length; i++ ) {
374 QualifiedName featureType = queries[i].getTypeNames()[0];
375 if ( caps.getFeatureTypeList().getFeatureType( featureType ) == null ) {
376 return false;
377 }
378 }
379 return true;
380 }
381 }
382 }