/**
* The contents of this file are subject to the license and copyright
* detailed in the LICENSE and NOTICE files at the root of the source
* tree and available online at
*
* http://www.dspace.org/license/
*/
package org.dspace.handle;
import java.sql.SQLException;
import java.util.Collections;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import net.handle.hdllib.Encoder;
import net.handle.hdllib.HandleException;
import net.handle.hdllib.HandleStorage;
import net.handle.hdllib.HandleValue;
import net.handle.hdllib.ScanCallback;
import net.handle.hdllib.Util;
import net.handle.util.StreamTable;
import org.apache.log4j.Logger;
import org.dspace.core.Context;
import org.dspace.handle.factory.HandleServiceFactory;
import org.dspace.handle.service.HandleService;
import org.dspace.servicemanager.DSpaceKernelImpl;
import org.dspace.servicemanager.DSpaceKernelInit;
import org.dspace.services.ConfigurationService;
import org.dspace.services.factory.DSpaceServicesFactory;
/**
* Extension to the CNRI Handle Server that translates requests to resolve
* handles into DSpace API calls. The implementation simply stubs out most of
* the methods, and delegates the rest to the
* {@link HandleService}. This only provides some of the
* functionality (namely, the resolving of handles to URLs) of the CNRI
* HandleStorage interface.
*
* <p>
* This class is intended to be embedded in the CNRI Handle Server. It conforms
* to the HandleStorage interface that was delivered with Handle Server version
* 6.2.0.
* </p>
*
* @author Peter Breton
* @version $Revision$
*/
public class HandlePlugin implements HandleStorage
{
/** log4j category */
private static Logger log = Logger.getLogger(HandlePlugin.class);
/** The DSpace service manager kernel **/
private static transient DSpaceKernelImpl kernelImpl;
/** References to DSpace Services **/
protected HandleService handleService;
protected ConfigurationService configurationService;
////////////////////////////////////////
// Non-Resolving methods -- unimplemented
////////////////////////////////////////
/**
* HandleStorage interface init method.
* <p>
* For DSpace, we have to startup the DSpace Kernel when HandlePlugin
* initializes, as the HandlePlugin relies on HandleService (and other services)
* which are loaded by the Kernel.
* @param st StreamTable
* @throws Exception if DSpace Kernel fails to startup
*/
@Override
public void init(StreamTable st) throws Exception
{
if (log.isInfoEnabled())
{
log.info("Called init (Starting DSpace Kernel)");
}
// Initialise the service manager kernel
try
{
kernelImpl = DSpaceKernelInit.getKernel(null);
if (!kernelImpl.isRunning())
{
kernelImpl.start();
}
} catch (Exception e)
{
// Failed to start so destroy it and log and throw an exception
try
{
kernelImpl.destroy();
}
catch (Exception e1)
{
// Nothing to do
}
String message = "Failed to startup DSpace Kernel: " + e.getMessage();
System.err.println(message);
e.printStackTrace();
throw new IllegalStateException(message, e);
}
// Get a reference to the HandleService & ConfigurationService
handleService = HandleServiceFactory.getInstance().getHandleService();
configurationService = DSpaceServicesFactory.getInstance().getConfigurationService();
}
/**
* HandleStorage interface method - not implemented.
*/
@Override
public void setHaveNA(byte[] theHandle, boolean haveit)
throws HandleException
{
// Not implemented
if (log.isInfoEnabled())
{
log.info("Called setHaveNA (not implemented)");
}
}
/**
* HandleStorage interface method - not implemented.
*/
@Override
public void createHandle(byte[] theHandle, HandleValue[] values)
throws HandleException
{
// Not implemented
if (log.isInfoEnabled())
{
log.info("Called createHandle (not implemented)");
}
}
/**
* HandleStorage interface method - not implemented.
*/
@Override
public boolean deleteHandle(byte[] theHandle) throws HandleException
{
// Not implemented
if (log.isInfoEnabled())
{
log.info("Called deleteHandle (not implemented)");
}
return false;
}
/**
* HandleStorage interface method - not implemented.
*/
@Override
public void updateValue(byte[] theHandle, HandleValue[] values)
throws HandleException
{
// Not implemented
if (log.isInfoEnabled())
{
log.info("Called updateValue (not implemented)");
}
}
/**
* HandleStorage interface method - not implemented.
*/
@Override
public void deleteAllRecords() throws HandleException
{
// Not implemented
if (log.isInfoEnabled())
{
log.info("Called deleteAllRecords (not implemented)");
}
}
/**
* HandleStorage interface method - not implemented.
*/
@Override
public void checkpointDatabase() throws HandleException
{
// Not implemented
if (log.isInfoEnabled())
{
log.info("Called checkpointDatabase (not implemented)");
}
}
/**
* HandleStorage interface shutdown() method.
* <P>
* For DSpace, we need to destroy the kernel created in init().
*/
@Override
public void shutdown()
{
if (log.isInfoEnabled())
{
log.info("Called shutdown (Destroying DSpace Kernel)");
}
// Destroy the DSpace kernel if it is still alive
if (kernelImpl != null)
{
kernelImpl.destroy();
kernelImpl = null;
}
}
/**
* HandleStorage interface method - not implemented.
*/
@Override
public void scanHandles(ScanCallback callback) throws HandleException
{
// Not implemented
if (log.isInfoEnabled())
{
log.info("Called scanHandles (not implemented)");
}
}
/**
* HandleStorage interface method - not implemented.
*/
@Override
public void scanNAs(ScanCallback callback) throws HandleException
{
// Not implemented
if (log.isInfoEnabled())
{
log.info("Called scanNAs (not implemented)");
}
}
////////////////////////////////////////
// Resolving methods
////////////////////////////////////////
/**
* Return the raw values for this handle. This implementation returns a
* single URL value.
*
* @param theHandle
* byte array representation of handle
* @param indexList
* ignored
* @param typeList
* ignored
* @return A byte array with the raw data for this handle. Currently, this
* consists of a single URL value.
* @throws HandleException
* If an error occurs while calling the Handle API.
*/
@Override
public byte[][] getRawHandleValues(byte[] theHandle, int[] indexList,
byte[][] typeList) throws HandleException
{
if (log.isInfoEnabled())
{
log.info("Called getRawHandleValues");
}
Context context = null;
try
{
if (theHandle == null)
{
throw new HandleException(HandleException.INTERNAL_ERROR);
}
String handle = Util.decodeString(theHandle);
context = new Context();
String url = handleService.resolveToURL(context, handle);
if (url == null)
{
return null;
}
HandleValue value = new HandleValue();
value.setIndex(100);
value.setType(Util.encodeString("URL"));
value.setData(Util.encodeString(url));
value.setTTLType((byte) 0);
value.setTTL(100);
value.setTimestamp(100);
value.setReferences(null);
value.setAdminCanRead(true);
value.setAdminCanWrite(false);
value.setAnyoneCanRead(true);
value.setAnyoneCanWrite(false);
List<HandleValue> values = new LinkedList<HandleValue>();
values.add(value);
byte[][] rawValues = new byte[values.size()][];
for (int i = 0; i < values.size(); i++)
{
HandleValue hvalue = values.get(i);
rawValues[i] = new byte[Encoder.calcStorageSize(hvalue)];
Encoder.encodeHandleValue(rawValues[i], 0, hvalue);
}
return rawValues;
}
catch (HandleException he)
{
throw he;
}
catch (Exception e)
{
if (log.isDebugEnabled())
{
log.debug("Exception in getRawHandleValues", e);
}
// Stack loss as exception does not support cause
throw new HandleException(HandleException.INTERNAL_ERROR);
}
finally
{
if (context != null)
{
try
{
context.complete();
}
catch (SQLException sqle)
{
}
}
}
}
/**
* Return true if we have this handle in storage.
*
* @param theHandle
* byte array representation of handle
* @return True if we have this handle in storage
* @throws HandleException
* If an error occurs while calling the Handle API.
*/
@Override
public boolean haveNA(byte[] theHandle) throws HandleException
{
if (log.isInfoEnabled())
{
log.info("Called haveNA");
}
/*
* Naming authority Handles are in the form: 0.NA/1721.1234
*
* 0.NA is basically the naming authority for naming authorities. For
* this simple implementation, we will just check that the prefix
* configured in dspace.cfg is the one in the request, returning true if
* this is the case, false otherwise.
*
* FIXME: For more complex Handle situations, this will need enhancing.
*/
// This parameter allows the dspace handle server to be capable of having multiple
// name authorities assigned to it. So long as the handle table the alternative prefixes
// defined the dspace will answer for those handles prefixes. This is not ideal and only
// works if the dspace instances assumes control over all the items in a prefix, but it
// does allow the admin to merge together two previously separate dspace instances each
// with their own prefixes and have the one instance handle both prefixes. In this case
// all new handle would be given a unified prefix but all old handles would still be
// resolvable.
if (configurationService.getBooleanProperty("handle.plugin.checknameauthority",true))
{
// First, construct a string representing the naming authority Handle
// we'd expect.
String expected = "0.NA/" + handleService.getPrefix();
// Which authority does the request pertain to?
String received = Util.decodeString(theHandle);
// Return true if they match
return expected.equals(received);
}
else
{
return true;
}
}
/**
* Return all handles in local storage which start with the naming authority
* handle.
*
* @param theNAHandle
* byte array representation of naming authority handle
* @return All handles in local storage which start with the naming
* authority handle.
* @throws HandleException
* If an error occurs while calling the Handle API.
*/
@Override
public Enumeration getHandlesForNA(byte[] theNAHandle)
throws HandleException
{
String naHandle = Util.decodeString(theNAHandle);
if (log.isInfoEnabled())
{
log.info("Called getHandlesForNA for NA " + naHandle);
}
Context context = null;
try
{
context = new Context();
List<String> handles = handleService.getHandlesForPrefix(context, naHandle);
List<byte[]> results = new LinkedList<byte[]>();
for (Iterator<String> iterator = handles.iterator(); iterator.hasNext();)
{
String handle = iterator.next();
// Transforms to byte array
results.add(Util.encodeString(handle));
}
return Collections.enumeration(results);
}
catch (SQLException sqle)
{
if (log.isDebugEnabled())
{
log.debug("Exception in getHandlesForNA", sqle);
}
// Stack loss as exception does not support cause
throw new HandleException(HandleException.INTERNAL_ERROR);
}
finally
{
if (context != null)
{
try
{
context.complete();
}
catch (SQLException sqle)
{
}
}
}
}
}