GmlFeatureInfoResponse.java

/* Copyright (c) 2001 - 2007 TOPP - www.openplans.org.  All rights reserved.
 * This code is licensed under the GPL 2.0 license, availible at the root
 * application directory.
 */
package org.vfny.geoserver.wms.responses.featureInfo;

import java.io.IOException;
import java.io.OutputStream;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;

import net.opengis.wfs.FeatureCollectionType;
import net.opengis.wfs.GetFeatureType;
import net.opengis.wfs.QueryType;
import net.opengis.wfs.WfsFactory;

import org.geoserver.config.GeoServer;
import org.geoserver.platform.Operation;
import org.geoserver.platform.Service;
import org.geoserver.platform.ServiceException;
import org.geoserver.wfs.xml.GML2OutputFormat;
import org.geoserver.wms.WMS;
import org.geotools.feature.FeatureCollection;
import org.geotools.gml2.bindings.GML2EncodingUtils;
import org.opengis.feature.simple.SimpleFeature;
import org.opengis.feature.simple.SimpleFeatureType;
import org.vfny.geoserver.wms.requests.GetFeatureInfoRequest;


/**
 * A GetFeatureInfo response handler specialized in producing GML data for a
 * GetFeatureInfo request.
 *
 * <p>
 * This class does not deals directly with GML encoding. Instead, it works by
 * taking the FeatureResults produced in <code>execute()</code> and constructs
 * a <code>GetFeaturesResult</code> wich is passed to a
 * <code>GML2FeatureResponseDelegate</code>, as if it where the result of a
 * GetFeature WFS request.
 * </p>
 *
 * @author Gabriel Roldan, Axios Engineering
 */
public class GmlFeatureInfoResponse extends AbstractFeatureInfoResponse {
    /**
     * The MIME type of the format this response produces:
     * <code>"application/vnd.ogc.gml"</code>
     */
    private static final String FORMAT = "application/vnd.ogc.gml";

    /**
     * Default constructor, sets up the supported output format string.
     */
    public GmlFeatureInfoResponse() {
        super.supportedFormats = Collections.singletonList(FORMAT);
    }

    /**
     * Returns any extra headers that this service might want to set in the HTTP
     * response object.
     *
     * @see org.vfny.geoserver.Response#getResponseHeaders()
     */
    public HashMap getResponseHeaders() {
        return new HashMap();
    }

    /**
     * Takes the <code>FeatureResult</code>s generated by the
     * <code>execute</code> method in the superclass and constructs a
     * <code>GetFeaturesResult</code> wich is passed to a
     * <code>GML2FeatureResponseDelegate</code>.
     *
     * @see AbstractFeatureInfoResponse#writeTo(OutputStream)
     */
    @Override
    public void writeTo(final OutputStream out) throws ServiceException, IOException {
        final GetFeatureInfoRequest fInfoReq = getRequest();
        final WMS wmsConfig = fInfoReq.getWMS();

        //the 'response' object we'll pass to our OutputFormat
        FeatureCollectionType features = WfsFactory.eINSTANCE.createFeatureCollectionType();
        
        //the 'request' object we'll pass to our OutputFormat
        GetFeatureType gfreq = WfsFactory.eINSTANCE.createGetFeatureType();
        gfreq.setBaseUrl(fInfoReq.getBaseUrl());

        for (Iterator i = results.iterator(); i.hasNext();) {
            FeatureCollection<SimpleFeatureType, SimpleFeature> fc = (FeatureCollection)i.next();
            features.getFeature().add(fc);
            
            QueryType qt = WfsFactory.eINSTANCE.createQueryType();
            String crs = GML2EncodingUtils.epsgCode(fc.getSchema().getCoordinateReferenceSystem());
            if (crs != null) {
                final String srsName = "EPSG:" + crs; 
                try {
                    qt.setSrsName(new URI(srsName));
                } catch (URISyntaxException e) {
                    throw new ServiceException("Unable to determite coordinate system for featureType " + fc.getSchema().getTypeName() + ".  Schema told us '" + srsName + "'", e);
                }
            }
            gfreq.getQuery().add(qt);
            
        }
        
        //this is a dummy wrapper around our 'request' object so that the new Dispatcher will accept it.
        Service serviceDesc = new Service("wms", null, null, Collections.EMPTY_LIST);
        Operation opDescriptor = new Operation("",serviceDesc,null, new Object[] { gfreq });
        
        final GeoServer gs = wmsConfig.getGeoServer();
        GML2OutputFormat format = new GML2OutputFormat(gs);
        format.write(features, out, opDescriptor);
    }

}