/*
* HandleServlet.java
*
* Version: $Revision: 4430 $
*
* Date: $Date: 2009-10-10 17:21:30 +0000 (Sat, 10 Oct 2009) $
*
* Copyright (c) 2002-2005, Hewlett-Packard Company and Massachusetts
* Institute of Technology. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of the Hewlett-Packard Company nor the name of the
* Massachusetts Institute of Technology nor the names of their
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
* TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*/
package org.dspace.app.webui.servlet;
import java.io.IOException;
import java.io.StringWriter;
import java.net.URLEncoder;
import java.sql.SQLException;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.lang.StringEscapeUtils;
import org.apache.log4j.Logger;
import org.dspace.app.webui.util.Authenticate;
import org.dspace.app.webui.util.JSPManager;
import org.dspace.app.webui.util.UIUtil;
import org.dspace.authorize.AuthorizeException;
import org.dspace.authorize.AuthorizeManager;
import org.dspace.content.Collection;
import org.dspace.content.Community;
import org.dspace.content.DCValue;
import org.dspace.content.DSpaceObject;
import org.dspace.content.Item;
import org.dspace.content.crosswalk.CrosswalkException;
import org.dspace.content.crosswalk.DisseminationCrosswalk;
import org.dspace.core.ConfigurationManager;
import org.dspace.core.Constants;
import org.dspace.core.Context;
import org.dspace.core.LogManager;
import org.dspace.core.PluginManager;
import org.dspace.eperson.EPerson;
import org.dspace.eperson.Group;
import org.dspace.eperson.Subscribe;
import org.dspace.handle.HandleManager;
import org.dspace.plugin.CollectionHomeProcessor;
import org.dspace.plugin.CommunityHomeProcessor;
import org.dspace.usage.UsageEvent;
import org.dspace.utils.DSpace;
import org.jdom.Element;
import org.jdom.Text;
import org.jdom.output.XMLOutputter;
/**
* Servlet for handling requests within a community or collection. The Handle is
* extracted from the URL, e.g: <code>/community/1721.1/1234</code>. If there
* is anything after the Handle, the request is forwarded to the appropriate
* servlet. For example:
* <P>
* <code>/community/1721.1/1234/simple-search</code>
* <P>
* would be forwarded to <code>/simple-search</code>. If there is nothing
* after the Handle, the community or collection home page is shown.
*
* @author Robert Tansley
* @version $Revision: 4430 $
*/
public class HandleServlet extends DSpaceServlet
{
/** log4j category */
private static Logger log = Logger.getLogger(DSpaceServlet.class);
/** For obtaining <meta> elements to put in the <head> */
private DisseminationCrosswalk xHTMLHeadCrosswalk;
public HandleServlet()
{
super();
xHTMLHeadCrosswalk = (DisseminationCrosswalk) PluginManager
.getNamedPlugin(DisseminationCrosswalk.class, "XHTML_HEAD_ITEM");
}
protected void doDSGet(Context context, HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException,
SQLException, AuthorizeException
{
String handle = null;
String extraPathInfo = null;
DSpaceObject dso = null;
// Original path info, of the form "1721.x/1234"
// or "1721.x/1234/extra/stuff"
String path = request.getPathInfo();
if (path != null)
{
// substring(1) is to remove initial '/'
path = path.substring(1);
try
{
// Extract the Handle
int firstSlash = path.indexOf('/');
int secondSlash = path.indexOf('/', firstSlash + 1);
if (secondSlash != -1)
{
// We have extra path info
handle = path.substring(0, secondSlash);
extraPathInfo = path.substring(secondSlash);
}
else
{
// The path is just the Handle
handle = path;
}
}
catch (NumberFormatException nfe)
{
// Leave handle as null
}
}
// Find out what the handle relates to
if (handle != null)
{
dso = HandleManager.resolveToObject(context, handle);
}
if (dso == null)
{
log.info(LogManager
.getHeader(context, "invalid_id", "path=" + path));
JSPManager.showInvalidIDError(request, response, StringEscapeUtils.escapeHtml(path), -1);
return;
}
// OK, we have a valid Handle. What is it?
if (dso.getType() == Constants.ITEM)
{
Item item = (Item) dso;
new DSpace().getEventService().fireEvent(
new UsageEvent(
UsageEvent.Action.VIEW,
request,
context,
dso));
// Only use last-modified if this is an anonymous access
// - caching content that may be generated under authorisation
// is a security problem
if (context.getCurrentUser() == null)
{
response.setDateHeader("Last-Modified", item
.getLastModified().getTime());
// Check for if-modified-since header
long modSince = request.getDateHeader("If-Modified-Since");
if (modSince != -1 && item.getLastModified().getTime() < modSince)
{
// Item has not been modified since requested date,
// hence bitstream has not; return 304
response.setStatus(HttpServletResponse.SC_NOT_MODIFIED);
}
else
{
// Display the item page
displayItem(context, request, response, item, handle);
}
}
else
{
// Display the item page
displayItem(context, request, response, item, handle);
}
}
else if (dso.getType() == Constants.COLLECTION)
{
Collection c = (Collection) dso;
new DSpace().getEventService().fireEvent(
new UsageEvent(
UsageEvent.Action.VIEW,
request,
context,
dso));
//UsageEvent ue = new UsageEvent();
//ue.fire(request, context, AbstractUsageEvent.VIEW,
// Constants.COLLECTION, dso.getID());
// Store collection location in request
request.setAttribute("dspace.collection", c);
/*
* Find the "parent" community the collection, mainly for
* "breadcrumbs" FIXME: At the moment, just grab the first community
* the collection is in. This should probably be more context
* sensitive when we have multiple inclusion.
*/
Community[] parents = c.getCommunities();
request.setAttribute("dspace.community", parents[0]);
/*
* Find all the "parent" communities for the collection for
* "breadcrumbs"
*/
request.setAttribute("dspace.communities", getParents(parents[0],
true));
// home page, or forward to another page?
if ((extraPathInfo == null) || (extraPathInfo.equals("/")))
{
collectionHome(context, request, response, parents[0], c);
}
else
{
// Forward to another servlet
request.getRequestDispatcher(extraPathInfo).forward(request,
response);
}
}
else if (dso.getType() == Constants.COMMUNITY)
{
Community c = (Community) dso;
new DSpace().getEventService().fireEvent(
new UsageEvent(
UsageEvent.Action.VIEW,
request,
context,
dso));
//UsageEvent ue = new UsageEvent();
//ue.fire(request, context, AbstractUsageEvent.VIEW,
// Constants.COMMUNITY, dso.getID());
// Store collection location in request
request.setAttribute("dspace.community", c);
/*
* Find all the "parent" communities for the community
*/
request.setAttribute("dspace.communities", getParents(c, false));
// home page, or forward to another page?
if ((extraPathInfo == null) || (extraPathInfo.equals("/")))
{
communityHome(context, request, response, c);
}
else
{
// Forward to another servlet
request.getRequestDispatcher(extraPathInfo).forward(request,
response);
}
}
else
{
// Shouldn't happen. Log and treat as invalid ID
log.info(LogManager.getHeader(context,
"Handle not an item, collection or community", "handle="
+ handle));
JSPManager.showInvalidIDError(request, response, StringEscapeUtils.escapeHtml(path), -1);
return;
}
}
/**
* Show an item page
*
* @param context
* Context object
* @param request
* the HTTP request
* @param response
* the HTTP response
* @param item
* the item
* @param handle
* the item's handle
*/
private void displayItem(Context context, HttpServletRequest request,
HttpServletResponse response, Item item, String handle)
throws ServletException, IOException, SQLException,
AuthorizeException
{
// Tombstone?
if (item.isWithdrawn())
{
JSPManager.showJSP(request, response, "/tombstone.jsp");
return;
}
// Ensure the user has authorisation
AuthorizeManager.authorizeAction(context, item, Constants.READ);
log
.info(LogManager.getHeader(context, "view_item", "handle="
+ handle));
// show edit link
if (item.canEdit())
{
// set a variable to create an edit button
request.setAttribute("admin_button", new Boolean(true));
}
// Get the collections
Collection[] collections = item.getCollections();
// For the breadcrumbs, get the first collection and the first community
// that is in. FIXME: Not multiple-inclusion friendly--should be
// smarter, context-sensitive
request.setAttribute("dspace.collection", item.getOwningCollection());
Community[] comms = item.getOwningCollection().getCommunities();
request.setAttribute("dspace.community", comms[0]);
/*
* Find all the "parent" communities for the collection
*/
request.setAttribute("dspace.communities", getParents(comms[0], true));
// Full or simple display?
boolean displayAll = false;
String modeParam = request.getParameter("mode");
if ((modeParam != null) && modeParam.equalsIgnoreCase("full"))
{
displayAll = true;
}
String headMetadata = "";
// Produce <meta> elements for header from crosswalk
try
{
List l = xHTMLHeadCrosswalk.disseminateList(item);
StringWriter sw = new StringWriter();
XMLOutputter xmlo = new XMLOutputter();
xmlo.output(new Text("\n"), sw);
for (int i = 0; i < l.size(); i++)
{
Element e = (Element) l.get(i);
// FIXME: we unset the Namespace so it's not printed.
// This is fairly yucky, but means the same crosswalk should
// work for Manakin as well as the JSP-based UI.
e.setNamespace(null);
xmlo.output(e, sw);
xmlo.output(new Text("\n"), sw);
}
headMetadata = sw.toString();
}
catch (CrosswalkException ce)
{
throw new ServletException(ce);
}
// Enable suggest link or not
boolean suggestEnable = false;
if (!ConfigurationManager.getBooleanProperty("webui.suggest.enable"))
{
// do nothing, the suggestLink is allready set to false
}
else
{
// it is in general enabled
suggestEnable= true;
// check for the enable only for logged in users option
if(!ConfigurationManager.getBooleanProperty("webui.suggest.loggedinusers.only"))
{
// do nothing, the suggestLink stays as it is
}
else
{
// check whether there is a logged in user
suggestEnable = (context.getCurrentUser() == null ? false : true);
}
}
// Set attributes and display
request.setAttribute("suggest.enable", new Boolean(suggestEnable));
request.setAttribute("display.all", new Boolean(displayAll));
request.setAttribute("item", item);
request.setAttribute("collections", collections);
request.setAttribute("dspace.layout.head", headMetadata);
JSPManager.showJSP(request, response, "/display-item.jsp");
}
/**
* Show a community home page, or deal with button press on home page
*
* @param context
* Context object
* @param request
* the HTTP request
* @param response
* the HTTP response
* @param community
* the community
*/
private void communityHome(Context context, HttpServletRequest request,
HttpServletResponse response, Community community)
throws ServletException, IOException, SQLException
{
// Handle click on a browse or search button
if (!handleButton(request, response, community.getHandle()))
{
// No button pressed, display community home page
log.info(LogManager.getHeader(context, "view_community",
"community_id=" + community.getID()));
// Get the collections within the community
Collection[] collections = community.getCollections();
// get any subcommunities of the community
Community[] subcommunities = community.getSubcommunities();
// perform any necessary pre-processing
preProcessCommunityHome(context, request, response, community);
// is the user a COMMUNITY_EDITOR?
if (community.canEditBoolean())
{
// set a variable to create an edit button
request.setAttribute("editor_button", new Boolean(true));
}
// can they add to this community?
if (AuthorizeManager.authorizeActionBoolean(context, community,
Constants.ADD))
{
// set a variable to create an edit button
request.setAttribute("add_button", new Boolean(true));
}
// can they remove from this community?
if (AuthorizeManager.authorizeActionBoolean(context, community,
Constants.REMOVE))
{
// set a variable to create an edit button
request.setAttribute("remove_button", new Boolean(true));
}
// Forward to community home page
request.setAttribute("community", community);
request.setAttribute("collections", collections);
request.setAttribute("subcommunities", subcommunities);
JSPManager.showJSP(request, response, "/community-home.jsp");
}
}
private void preProcessCommunityHome(Context context, HttpServletRequest request,
HttpServletResponse response, Community community)
throws ServletException, IOException, SQLException
{
try
{
CommunityHomeProcessor[] chp = (CommunityHomeProcessor[]) PluginManager.getPluginSequence(CommunityHomeProcessor.class);
for (int i = 0; i < chp.length; i++)
{
chp[i].process(context, request, response, community);
}
}
catch (Exception e)
{
log.error("caught exception: ", e);
throw new ServletException(e);
}
}
/**
* Show a collection home page, or deal with button press on home page
*
* @param context
* Context object
* @param request
* the HTTP request
* @param response
* the HTTP response
* @param community
* the community
* @param collection
* the collection
*/
private void collectionHome(Context context, HttpServletRequest request,
HttpServletResponse response, Community community,
Collection collection) throws ServletException, IOException,
SQLException, AuthorizeException
{
// Handle click on a browse or search button
if (!handleButton(request, response, collection.getHandle()))
{
// Will need to know whether to commit to DB
boolean updated = false;
// No search or browse button pressed, check for
if (request.getParameter("submit_subscribe") != null)
{
// Subscribe button pressed.
// Only registered can subscribe, so redirect unless logged in.
if (context.getCurrentUser() == null &&
!Authenticate
.startAuthentication(context, request, response))
return;
else
{
Subscribe.subscribe(context, context.getCurrentUser(),
collection);
updated = true;
}
}
else if (request.getParameter("submit_unsubscribe") != null)
{
Subscribe.unsubscribe(context, context.getCurrentUser(),
collection);
updated = true;
}
// display collection home page
log.info(LogManager.getHeader(context, "view_collection",
"collection_id=" + collection.getID()));
// perform any necessary pre-processing
preProcessCollectionHome(context, request, response, collection);
// Is the user logged in/subscribed?
EPerson e = context.getCurrentUser();
boolean subscribed = false;
if (e != null)
{
subscribed = Subscribe.isSubscribed(context, e, collection);
// is the user a COLLECTION_EDITOR?
if (collection.canEditBoolean(true))
{
// set a variable to create an edit button
request.setAttribute("editor_button", new Boolean(true));
}
// can they admin this collection?
if (AuthorizeManager.authorizeActionBoolean(context,
collection, Constants.COLLECTION_ADMIN))
{
request.setAttribute("admin_button", new Boolean(true));
// give them a button to manage submitter list
// what group is the submitter?
Group group = collection.getSubmitters();
if (group != null)
{
request.setAttribute("submitters", group);
}
}
// can they submit to this collection?
if (AuthorizeManager.authorizeActionBoolean(context,
collection, Constants.ADD))
{
request
.setAttribute("can_submit_button",
new Boolean(true));
}
else
{
request.setAttribute("can_submit_button",
new Boolean(false));
}
}
// Forward to collection home page
request.setAttribute("collection", collection);
request.setAttribute("community", community);
request.setAttribute("logged.in", new Boolean(e != null));
request.setAttribute("subscribed", new Boolean(subscribed));
JSPManager.showJSP(request, response, "/collection-home.jsp");
if (updated)
{
context.complete();
}
}
}
private void preProcessCollectionHome(Context context, HttpServletRequest request,
HttpServletResponse response, Collection collection)
throws ServletException, IOException, SQLException
{
try
{
CollectionHomeProcessor[] chp = (CollectionHomeProcessor[]) PluginManager.getPluginSequence(CollectionHomeProcessor.class);
for (int i = 0; i < chp.length; i++)
{
chp[i].process(context, request, response, collection);
}
}
catch (Exception e)
{
log.error("caught exception: ", e);
throw new ServletException(e);
}
}
/**
* Check to see if a browse or search button has been pressed on a community
* or collection home page. If so, redirect to the appropriate URL.
*
* @param request
* HTTP request
* @param response
* HTTP response
* @param handle
* Handle of the community/collection home page
*
* @return true if a browse/search button was pressed and the user was
* redirected
*/
private boolean handleButton(HttpServletRequest request,
HttpServletResponse response, String handle) throws IOException
{
String button = UIUtil.getSubmitButton(request, "");
String location = request.getParameter("location");
String prefix = "/";
String url = null;
if (location == null)
{
return false;
}
/*
* Work out the "prefix" to which to redirect If "/", scope is all of
* DSpace, so prefix is "/" If prefix is a handle, scope is a community
* or collection, so "/handle/1721.x/xxxx/" is the prefix.
*/
if (!location.equals("/"))
{
prefix = "/handle/" + location + "/";
}
if (button.equals("submit_search")
|| (request.getParameter("query") != null))
{
/*
* Have to check for search button and query - in some browsers,
* typing a query into the box and hitting return doesn't produce a
* submit button parameter. Redirect to appropriate search page
*/
url = request.getContextPath()
+ prefix
+ "simple-search?query="
+ URLEncoder.encode(request.getParameter("query"),
Constants.DEFAULT_ENCODING);
}
// If a button was pressed, redirect to appropriate page
if (url != null)
{
response.sendRedirect(response.encodeRedirectURL(url));
return true;
}
return false;
}
/**
* Utility method to obtain the titles for the Items in the given list.
*
* @param items List of Items
* @return array of corresponding titles
*/
private String[] getItemTitles(List items)
{
String[] titles = new String[items.size()];
for (int i = 0; i < items.size(); i++)
{
Item item = (Item) items.get(i);
// FIXME: Should probably check for preferred language?
DCValue[] titlesForThis = item.getDC("title", null, Item.ANY);
// Just use the first title, if any
if (titlesForThis.length == 0)
{
// No title at all!
titles[i] = null;
}
else
{
// Use first title
titles[i] = titlesForThis[0].value;
}
}
return titles;
}
/**
* Utility method obtain URLs for the most recent items
*
* @param context
* DSpace context
* @param items
* the items to get URLs for
* @return an array of URLs (in Strings) corresponding to those items
*/
private String[] getItemURLs(Context context, List items)
throws SQLException
{
String[] urls = new String[items.size()];
for (int i = 0; i < items.size(); i++)
{
Item item = (Item) items.get(i);
urls[i] = "/handle/" + item.getHandle();
}
return urls;
}
/**
* Utility method to produce a list of parent communities for a given
* community, ending with the passed community, if include is true. If
* commmunity is top-level, the array will be empty, or contain only the
* passed community, if include is true. The array is ordered highest level
* to lowest
*/
private Community[] getParents(Community c, boolean include)
throws SQLException
{
// Find all the "parent" communities for the community
Community[] parents = c.getAllParents();
// put into an array in reverse order
int revLength = include ? (parents.length + 1) : parents.length;
Community[] reversedParents = new Community[revLength];
int index = parents.length - 1;
for (int i = 0; i < parents.length; i++)
{
reversedParents[i] = parents[index - i];
}
if (include)
{
reversedParents[revLength - 1] = c;
}
return reversedParents;
}
}