catalogdispatcher.java

联合国农粮署牵头开发的geonetwork源代码最新版

//=============================================================================
//===	Copyright (C) 2001-2007 Food and Agriculture Organization of the
//===	United Nations (FAO-UN), United Nations World Food Programme (WFP)
//===	and United Nations Environment Programme (UNEP)
//===
//===	This program is free software; you can redistribute it and/or modify
//===	it under the terms of the GNU General Public License as published by
//===	the Free Software Foundation; either version 2 of the License, or (at
//===	your option) any later version.
//===
//===	This program is distributed in the hope that it will be useful, but
//===	WITHOUT ANY WARRANTY; without even the implied warranty of
//===	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
//===	General Public License for more details.
//===
//===	You should have received a copy of the GNU General Public License
//===	along with this program; if not, write to the Free Software
//===	Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
//===
//===	Contact: Jeroen Ticheler - FAO - Viale delle Terme di Caracalla 2,
//===	Rome - Italy. email: [e-mail]
//==============================================================================

package org.fao.geonet.kernel.csw;

import java.io.File;
import java.io.IOException;
import java.io.StringReader;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.xml.XMLConstants;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.Source;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamSource;
import javax.xml.validation.Schema;
import javax.xml.validation.SchemaFactory;
import javax.xml.validation.Validator;
import jeeves.server.context.ServiceContext;
import jeeves.server.sources.ServiceRequest.InputMethod;
import jeeves.server.sources.ServiceRequest.OutputMethod;
import jeeves.utils.SOAPUtil;
import jeeves.utils.Util;
import jeeves.utils.Xml;
import org.fao.geonet.csw.common.exceptions.CatalogException;
import org.fao.geonet.csw.common.exceptions.MissingParameterValueEx;
import org.fao.geonet.csw.common.exceptions.NoApplicableCodeEx;
import org.fao.geonet.csw.common.exceptions.OperationNotSupportedEx;
import org.fao.geonet.kernel.csw.services.DescribeRecord;
import org.fao.geonet.kernel.csw.services.GetCapabilities;
import org.fao.geonet.kernel.csw.services.GetDomain;
import org.fao.geonet.kernel.csw.services.GetRecordById;
import org.fao.geonet.kernel.csw.services.GetRecords;
import org.fao.geonet.kernel.csw.services.Harvest;
import org.fao.geonet.kernel.csw.services.Transaction;
import org.jdom.Element;
import org.w3c.dom.Document;
import org.xml.sax.SAXException;

import static org.fao.geonet.csw.common.Csw.*;

//=============================================================================

public class CatalogDispatcher
{
	private HashMap<String, CatalogService> hmServices = new HashMap<String, CatalogService>();

	//---------------------------------------------------------------------------
	//---
	//--- Constructor
	//---
	//---------------------------------------------------------------------------

	public CatalogDispatcher()
	{
		register(new DescribeRecord());
		register(new GetCapabilities());
		register(new GetDomain());
		register(new GetRecordById());
		register(new GetRecords());
		register(new Harvest());
		register(new Transaction());
	}

	//---------------------------------------------------------------------------

	private void register(CatalogService s)
	{
		hmServices.put(s.getName(), s);
	}

	//---------------------------------------------------------------------------
	//---
	//--- API methods
	//---
	//---------------------------------------------------------------------------

	public Element dispatch(Element request, ServiceContext context)
	{
		context.info("Received:\n"+Xml.getString(request));

		InputMethod  im = context.getInputMethod();
		OutputMethod om = context.getOutputMethod();

		boolean inSOAP  = (im == InputMethod.SOAP);
		boolean outSOAP = (inSOAP || om == OutputMethod.SOAP);

		CatalogException exc;

		try
		{
			if (inSOAP)
				request = SOAPUtil.unembed(request);

			Element response = dispatchI(request, context);

			if (outSOAP)
				response = SOAPUtil.embed(response);

//			validateResponse(context, response);

			return response;
		}

		catch(CatalogException e)
		{
			exc = e;
		}

		catch(Exception e)
		{
			context.info("Exception stack trace : \n"+ Util.getStackTrace(e));
			exc = new NoApplicableCodeEx(e.toString());
		}

		Element response = CatalogException.marshal(exc);
		boolean sender   = (exc instanceof NoApplicableCodeEx);

		if (outSOAP)
			return SOAPUtil.embedExc(response, sender, exc.getCode(), exc.toString());

		//TODO: need to set the status code

		return response;
	}

	//---------------------------------------------------------------------------
	//---
	//--- Private method
	//---
	//---------------------------------------------------------------------------

	private Element dispatchI(Element request, ServiceContext context) throws CatalogException
	{
		InputMethod im = context.getInputMethod();

		if (im == InputMethod.XML || im == InputMethod.SOAP)
		{
			String operation = request.getName();

			CatalogService cs = hmServices.get(operation);

			if (cs == null)
				throw new OperationNotSupportedEx(operation);

			context.info("Dispatching operation : "+ operation);

			return cs.execute(request, context);
		}

		else //--- GET or POST/www-encoded request
		{
			Map<String, String> params = extractParams(request);

			String operation = params.get("request");

			if (operation == null)
				throw new MissingParameterValueEx("request");

			CatalogService cs = hmServices.get(operation);

			if (cs == null)
				throw new OperationNotSupportedEx(operation);

			request = cs.adaptGetRequest(params);

			context.debug("Adapted GET request is:\n"+Xml.getString(request));
			context.info("Dispatching operation : "+ operation);

			return cs.execute(request, context);
		}
	}

	//---------------------------------------------------------------------------

	private Map<String, String> extractParams(Element request)
	{
		HashMap<String, String> hm = new HashMap<String, String>();

		List params = request.getChildren();

		for(int i=0; i<params.size(); i++)
		{
			Element param = (Element) params.get(i);

			String name = param.getName().toLowerCase();
			String value= param.getTextTrim();

			hm.put(name, value);
		}

		return hm;
	}

	//---------------------------------------------------------------------------

	private void validateResponse(ServiceContext context, Element response)
	{
//		String xml  = Xml.getString(new org.jdom.Document(response));
//		String path = context.getAppPath() +VALIDATE_PATH;
//
//		byte
//
//		DocumentBuilder parser = DocumentBuilderFactory.newInstance().newDocumentBuilder();
//		Document        doc    = parser.parse(new StringReader(xml));
//
//		// create a SchemaFactory capable of understanding WXS schemas
//		SchemaFactory factory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
//
//		// load a WXS schema, represented by a Schema instance
//		Source schemaFile = new StreamSource(new File(path));
//		Schema schema = factory.newSchema(schemaFile);
//
//		// create a Validator instance, which can be used to validate an instance document
//		Validator validator = schema.newValidator();
//
//		// validate the DOM tree
//
//		try
//		{
//			validator.validate(new DOMSource(doc));
//		}
//		catch (SAXException e)
//		{
//			// instance document is invalid!
//   	}
//		catch (IOException e)
//		{
//		}
	}

	//---------------------------------------------------------------------------

	private final static String VALIDATE_PATH = "web/xml/validation/csw/2.0.1/CSW-discovery.xsd";
}

//=============================================================================