WCSCapabilitiesResponse.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.wcs.responses;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.charset.Charset;
import java.util.HashMap;
import java.util.logging.Logger;

import javax.xml.transform.TransformerException;

import org.geoserver.config.GeoServer;
import org.geoserver.config.GeoServerInfo;
import org.geoserver.config.ServiceInfo;
import org.geoserver.platform.ServiceException;
import org.springframework.context.ApplicationContext;
import org.vfny.geoserver.Request;
import org.vfny.geoserver.Response;
import org.vfny.geoserver.util.requests.CapabilitiesRequest;
import org.vfny.geoserver.wcs.WcsException;
import org.vfny.geoserver.wcs.WcsException.WcsExceptionCode;


/**
 * DOCUMENT ME!
 *
 * @author $Author: Alessio Fabiani (alessio.fabiani@gmail.com) $ (last
 *         modification)
 * @author $Author: Simone Giannecchini (simboss1@gmail.com) $ (last
 *         modification)
 */
public class WCSCapabilitiesResponse implements Response {
    /** package's logger */
    private static final Logger LOGGER = org.geotools.util.logging.Logging.getLogger(WCSCapabilitiesResponse.class.getPackage()
                                                                                       .getName());

    /**
     * Byte array holding the raw content of the capabilities document,
     * generated in <code>execute()</code>
     */
    private byte[] rawResponse;

    private ApplicationContext applicationContext;

	public WCSCapabilitiesResponse(ApplicationContext applicationContext) {
		this.applicationContext = applicationContext;
	}
	
    /**
     * 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 null;
    }

    /**
     * DOCUMENT ME!
     *
     * @param request
     *            DOCUMENT ME!
     *
     * @throws ServiceException
     *             DOCUMENT ME!
     * @throws IllegalArgumentException
     *             DOCUMENT ME!
     * @throws WCSException
     *             DOCUMENT ME!
     */
    public void execute(Request request) throws ServiceException {
        if (!(request instanceof CapabilitiesRequest)) {
            throw new IllegalArgumentException("Not a GetCapabilities Request");
        }
        
        CapabilitiesRequest capreq = (CapabilitiesRequest)request;
        int reqUS = -1;
        if (capreq.getUpdateSequence() != null) {
	        try {
	        	reqUS = Integer.parseInt(capreq.getUpdateSequence());
	        } catch (NumberFormatException nfe) {
	        	throw new ServiceException("GeoServer only accepts numbers in the updateSequence parameter");
	        }
        }
        GeoServerInfo gsInfo = request.getServiceConfig().getGeoServer().getGlobal();
		int geoUS = gsInfo.getUpdateSequence();
    	if (reqUS > geoUS) {
    		throw new WcsException("Client supplied an updateSequence that is greater than the current sever updateSequence", WcsExceptionCode.InvalidUpdateSequence, "");
    	}
    	if (reqUS == geoUS) {
    		throw new WcsException("WCS capabilities document is current (updateSequence = " + geoUS + ")", WcsExceptionCode.CurrentUpdateSequence, "");
    	}
    	//otherwise it's a normal response...

        WCSCapsTransformer transformer = new WCSCapsTransformer(request
				.getBaseUrl(), applicationContext);

        transformer.setIndentation(2);
        transformer.setEncoding(Charset.forName(gsInfo.getCharset()));
        
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        try {
            transformer.transform(request, out);
        } catch (TransformerException e) {
            throw new WcsException(e);
        }

        this.rawResponse = out.toByteArray();
    }

    /**
     * Returns the fixed capabilities MIME type (application/vnd.ogc.WCS_xml) as
     * specified in whe WCS spec, version 1.1.1, section 6.5.3, table 3.
     *
     * @param gs
     *            DOCUMENT ME!
     *
     * @return the capabilities document MIME type.
     *
     * @throws IllegalStateException
     *             if the response was not yet produced.
     */
    public String getContentType(GeoServer gs) throws IllegalStateException {
        if (rawResponse == null) {
            throw new IllegalStateException("execute() not called or not succeed.");
        }

        return "text/xml; charset=" + gs.getGlobal().getCharset();
    }

    /**
     * Just returns <code>null</code>, since no special encoding is applyed
     * to the output data.
     *
     * @return <code>null</code>
     */
    public String getContentEncoding() {
        return null;
    }

    /**
     * Just returns <code>null</code>, since no special encoding is applyed
     * to the output data.
     *
     * @return <code>null</code>
     */
    public String getContentDisposition() {
        return null;
    }

    /**
     * Writes the capabilities document generated in <code>execute()</code> to
     * the given output stream.
     *
     * @param out
     *            the capabilities document destination
     *
     * @throws ServiceException
     *             never, since the whole content was aquired in
     *             <code>execute()</code>
     * @throws IOException
     *             if it is thrown while writing to <code>out</code>
     * @throws IllegalStateException
     *             if <code>execute()</code> was not called/succeed before
     *             this method is called.
     */
    public void writeTo(OutputStream out) throws ServiceException, IOException {
        if (rawResponse == null) {
            throw new IllegalStateException("execute() not called or not succeed.");
        }

        out.write(rawResponse);
    }

    /**
     * Does nothing, since no processing is done after <code>execute()</code>
     * has returned.
     *
     * @param gs
     *            the service instance
     */
    public void abort(ServiceInfo gs) {
    }
}