001 //$HeadURL: https://svn.wald.intevation.org/svn/deegree/base/branches/2.3_testing/src/org/deegree/ogcwebservices/wfs/DescribeFeatureTypeHandler.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 java.io.IOException;
039 import java.net.URI;
040 import java.util.HashSet;
041 import java.util.Set;
042
043 import javax.xml.transform.TransformerException;
044
045 import org.deegree.datatypes.QualifiedName;
046 import org.deegree.framework.log.ILogger;
047 import org.deegree.framework.log.LoggerFactory;
048 import org.deegree.framework.xml.XMLFragment;
049 import org.deegree.framework.xml.XMLTools;
050 import org.deegree.framework.xml.XSLTDocument;
051 import org.deegree.framework.xml.schema.XSDocument;
052 import org.deegree.i18n.Messages;
053 import org.deegree.io.datastore.schema.MappedFeatureType;
054 import org.deegree.io.datastore.schema.MappedGMLSchema;
055 import org.deegree.model.feature.schema.FeatureType;
056 import org.deegree.ogcbase.CommonNamespaces;
057 import org.deegree.ogcwebservices.OGCWebServiceException;
058 import org.deegree.ogcwebservices.getcapabilities.DCPType;
059 import org.deegree.ogcwebservices.getcapabilities.HTTP;
060 import org.deegree.ogcwebservices.wfs.capabilities.WFSCapabilities;
061 import org.deegree.ogcwebservices.wfs.capabilities.WFSOperationsMetadata;
062 import org.deegree.ogcwebservices.wfs.operation.DescribeFeatureType;
063 import org.deegree.ogcwebservices.wfs.operation.FeatureTypeDescription;
064 import org.w3c.dom.Element;
065 import org.xml.sax.SAXException;
066
067 /**
068 * Handler for {@link DescribeFeatureType} requests.
069 *
070 * @author <a href="mailto:poth@lat-lon.de">Andreas Poth </a>
071 * @author <a href="mailto:deshmukh@lat-lon.de">Anup Deshmukh </a>
072 * @author <a href="mailto:schneider@lat-lon.de">Markus Schneider</a>
073 * @author last edited by: $Author: mschneider $
074 *
075 * @version $Revision: 18195 $, $Date: 2009-06-18 17:55:39 +0200 (Do, 18. Jun 2009) $
076 */
077 class DescribeFeatureTypeHandler {
078
079 private static final ILogger LOG = LoggerFactory.getLogger( DescribeFeatureTypeHandler.class );
080
081 private static final String TEMPLATE_FILE = "SchemaContainerTemplate.xml";
082
083 private static final URI XSNS = CommonNamespaces.XSNS;
084
085 private static final String XS_PREFIX = CommonNamespaces.XS_PREFIX;
086
087 private WFService wfs;
088
089 private String describeFeatureTypeURL;
090
091 private static XSLTDocument annotationFilter;
092
093 static {
094 try {
095 annotationFilter = new XSLTDocument();
096 annotationFilter.load( DescribeFeatureTypeHandler.class.getResource( "descfeaturetype.xsl" ) );
097 } catch ( Exception e ) {
098 e.printStackTrace();
099 LOG.logError( "Could not read describe feature type annotation filter XSLT-script:" + e.getMessage(), e );
100 }
101 }
102
103 /**
104 * Creates a new <code>DescribeFeatureHandler</code> for the given {@link WFService}.
105 *
106 * @param wfs
107 * associated WFService
108 */
109 DescribeFeatureTypeHandler( WFService wfs ) throws OGCWebServiceException {
110 this.wfs = wfs;
111 this.describeFeatureTypeURL = getDescribeFeatureTypeURL();
112 }
113
114 /**
115 * Handles a DescribeFeatureType request.
116 * <p>
117 * If the requested feature types are all defined in the same GML application schema, the
118 * corresponding document is returned. Otherwise, a container schema document is generated which
119 * imports all necessary GML application schemas.
120 *
121 * @param request
122 * DescribeFeatureType request
123 * @return schema document encapsulated in a FeatureTypeDescription
124 */
125 FeatureTypeDescription handleRequest( DescribeFeatureType request )
126 throws OGCWebServiceException {
127
128 XSDocument schema = null;
129 // used to collect and eliminate duplicate GML application schema instances
130 Set<MappedGMLSchema> schemaSet = new HashSet<MappedGMLSchema>();
131
132 QualifiedName[] ftNames = request.getTypeNames();
133 if ( ftNames == null || ftNames.length == 0 ) {
134 // no feature types specified in request -> describe all visible feature types
135 for ( MappedFeatureType ft : this.wfs.getMappedFeatureTypes().values() ) {
136 if ( ft.isVisible() ) {
137 schemaSet.add( ft.getGMLSchema() );
138 }
139 }
140 } else {
141 for ( QualifiedName ftName : ftNames ) {
142 MappedFeatureType ft = this.wfs.getMappedFeatureType( ftName );
143 if ( ft == null ) {
144 String msg = Messages.getMessage( "WFS_FEATURE_TYPE_UNKNOWN", ftName );
145 throw new OGCWebServiceException( this.getClass().getName(), msg );
146 }
147 if ( !ft.isVisible() ) {
148 String msg = Messages.getMessage( "WFS_FEATURE_TYPE_INVISIBLE", ftName );
149 throw new OGCWebServiceException( this.getClass().getName(), msg );
150 }
151 schemaSet.add( ft.getGMLSchema() );
152 }
153 }
154
155 if ( schemaSet.size() == 1 ) {
156 schema = schemaSet.iterator().next().getDocument();
157 try {
158 schema = filterAnnotations( schema );
159 } catch ( TransformerException e ) {
160 String msg = "Could not remove annotations from annotated GML application schema.";
161 LOG.logError( msg, e );
162 throw new OGCWebServiceException( this.getClass().getName(), msg );
163 }
164 } else {
165 try {
166 schema = getXSDContainer( schemaSet );
167 schema = filterAnnotations( schema );
168 } catch ( Exception e ) {
169 String msg = "Could not create XSD container document.";
170 LOG.logError( msg, e );
171 throw new OGCWebServiceException( this.getClass().getName(), msg );
172 }
173 }
174 return new FeatureTypeDescription( schema );
175 }
176
177 /**
178 * Filters out all annotation elements from the schema.
179 *
180 * @param schema
181 * @return filter document (without annotation elements)
182 */
183 private XSDocument filterAnnotations( XSDocument schema )
184 throws TransformerException {
185
186 XMLFragment xml = annotationFilter.transform( schema );
187 schema.setRootElement( xml.getRootElement() );
188 return schema;
189 }
190
191 /**
192 * Creates a container schema document that imports all necessary GML application schemas.
193 *
194 * @param schemaSet
195 * @return container schema document
196 */
197 private XSDocument getXSDContainer( Set<MappedGMLSchema> schemaSet )
198 throws IOException, SAXException {
199
200 XSDocument schemaDoc = new XSDocument();
201 schemaDoc.load( this.getClass().getResource( TEMPLATE_FILE ) );
202 for ( MappedGMLSchema schema : schemaSet ) {
203 FeatureType representative = schema.getFeatureTypes()[0];
204 appendImportElement( schemaDoc.getRootElement(), representative.getName() );
205 }
206
207 return schemaDoc;
208 }
209
210 /**
211 * It is assumed that the passed Element is the root of an XML schema description. The different
212 * schema described by the passed <code>XMLFragment</code> will be included by adding an
213 * import statement to the root schema:
214 *
215 * <pre>
216 * <?xml version="1.0" ?>
217 * <schema targetNamespace="http://www.someserver.com/myns"
218 * xmlns:myns=http://www.someserver.com/myns
219 * xmlns="http://www.w3.org/2001/XMLSchema"
220 * elementFormDefault="qualified"
221 * attributeFormDefault="unqualified">
222 *
223 * <import namespace="http://www.server01.com/ns01"
224 * schemaLocation="http://www.deegree.org/wfs?request=DescribeFeatureType&typeName=ns01:TreesA_1M"/>
225 * </schema>
226 * </pre>
227 *
228 * @param root
229 * root element of the target schema
230 * @param representative
231 * that shall be imported to the target schema
232 */
233 private void appendImportElement( Element root, QualifiedName representative ) {
234
235 MappedFeatureType featureType = this.wfs.getMappedFeatureType( representative );
236 MappedGMLSchema schema = featureType.getGMLSchema();
237
238 URI targetNS = schema.getTargetNamespace();
239 Element importElement = XMLTools.appendElement( root, XSNS, XS_PREFIX + ":import" );
240
241 StringBuffer describeFeatureTypeURL = new StringBuffer( this.describeFeatureTypeURL );
242 if ( !this.describeFeatureTypeURL.endsWith( "?" ) ) {
243 describeFeatureTypeURL.append( "?" );
244 }
245 describeFeatureTypeURL.append( "SERVICE=WFS&VERSION=1.1.0&REQUEST=DescribeFeatureType&TYPENAME=" );
246 describeFeatureTypeURL.append( representative.getPrefixedName() );
247 describeFeatureTypeURL.append( "&NAMESPACE=xmlns(" );
248 describeFeatureTypeURL.append( representative.getPrefix() ).append( "=" );
249 describeFeatureTypeURL.append( representative.getNamespace() );
250 describeFeatureTypeURL.append( ")" );
251
252 importElement.setAttribute( "namespace", targetNS.toString() );
253 importElement.setAttribute( "schemaLocation", describeFeatureTypeURL.toString() );
254 }
255
256 /**
257 * Extracts one valid URL with HTTP binding that can be used for describe feature type
258 * operations.
259 *
260 * @return a valid URL for DescribeFeatureType requests
261 * @throws OGCWebServiceException
262 */
263 private String getDescribeFeatureTypeURL()
264 throws OGCWebServiceException {
265 WFSCapabilities capa = wfs.getCapabilities();
266 WFSOperationsMetadata om = (WFSOperationsMetadata) capa.getOperationsMetadata();
267 DCPType[] dcp = om.getDescribeFeatureType().getDCPs();
268 int i = 0;
269 while ( i < dcp.length - 1 && !( dcp[i].getProtocol() instanceof HTTP ) ) {
270 i++;
271 }
272
273 if ( i >= dcp.length ) {
274 String msg = "No HTTP DCP for DescribeFeatureType operation defined in WFS capabilities.";
275 throw new OGCWebServiceException( this.getClass().getName(), msg );
276 }
277
278 String address = null;
279 if ( ( (HTTP) dcp[i].getProtocol() ).getGetOnlineResources() != null
280 && ( (HTTP) dcp[i].getProtocol() ).getGetOnlineResources().length > 0 ) {
281 address = ( (HTTP) dcp[i].getProtocol() ).getGetOnlineResources()[0].toExternalForm();
282 } else {
283 address = ( (HTTP) dcp[i].getProtocol() ).getPostOnlineResources()[0].toExternalForm();
284 }
285 return address;
286 }
287 }