001/*
002 * This library is part of OpenCms -
003 * the Open Source Content Management System
004 *
005 * Copyright (c) Alkacon Software GmbH & Co. KG (http://www.alkacon.com)
006 *
007 * This library is free software; you can redistribute it and/or
008 * modify it under the terms of the GNU Lesser General Public
009 * License as published by the Free Software Foundation; either
010 * version 2.1 of the License, or (at your option) any later version.
011 *
012 * This library is distributed in the hope that it will be useful,
013 * but WITHOUT ANY WARRANTY; without even the implied warranty of
014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
015 * Lesser General Public License for more details.
016 *
017 * For further information about Alkacon Software, please see the
018 * company website: http://www.alkacon.com
019 *
020 * For further information about OpenCms, please see the
021 * project website: http://www.opencms.org
022 *
023 * You should have received a copy of the GNU Lesser General Public
024 * License along with this library; if not, write to the Free Software
025 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
026 */
027
028package org.opencms.main;
029
030import org.opencms.ade.detailpage.CmsDetailPageResourceHandler;
031import org.opencms.db.CmsAlias;
032import org.opencms.db.CmsRewriteAliasMatcher;
033import org.opencms.file.CmsObject;
034import org.opencms.file.CmsResource;
035import org.opencms.gwt.shared.alias.CmsAliasMode;
036import org.opencms.i18n.CmsMessageContainer;
037import org.opencms.security.CmsPermissionViolationException;
038import org.opencms.security.CmsSecurityException;
039import org.opencms.util.CmsFileUtil;
040import org.opencms.workplace.CmsWorkplace;
041
042import java.io.IOException;
043import java.util.List;
044
045import javax.servlet.http.HttpServletRequest;
046import javax.servlet.http.HttpServletResponse;
047
048import org.apache.commons.logging.Log;
049
050/**
051 * Resource init handler for detail-pages.<p>
052 *
053 * @since 8.0.0
054 */
055public class CmsAliasResourceHandler implements I_CmsResourceInit {
056
057    /** The attribute containing the detail content resource. */
058    public static final String ATTR_DETAIL_CONTENT_RESOURCE = "__opencms_detail_content_resource";
059
060    /** The log object for this class. */
061    private static final Log LOG = CmsLog.getLog(CmsDetailPageResourceHandler.class);
062
063    /**
064     * Default constructor.<p>
065     */
066    public CmsAliasResourceHandler() {
067
068        // empty
069    }
070
071    /**
072     * @see org.opencms.main.I_CmsResourceInit#initResource(org.opencms.file.CmsResource, org.opencms.file.CmsObject, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
073     */
074    public CmsResource initResource(
075        CmsResource resource,
076        CmsObject cms,
077        HttpServletRequest req,
078        HttpServletResponse res) throws CmsResourceInitException, CmsSecurityException {
079
080        // check if the resource was already found or the path starts with '/system/'
081        boolean abort = (resource != null) || cms.getRequestContext().getUri().startsWith(CmsWorkplace.VFS_PATH_SYSTEM);
082        if (abort) {
083            // skip in all cases above
084            return resource;
085        }
086
087        String path = cms.getRequestContext().getUri();
088        path = CmsFileUtil.removeTrailingSeparator(path);
089        String siteRoot = cms.getRequestContext().getSiteRoot();
090        if ("".equals(siteRoot)) {
091            siteRoot = OpenCms.getSiteManager().getSiteRoot(path);
092            if (siteRoot == null) {
093                siteRoot = "";
094            }
095        }
096        try {
097            String sitePath = path;
098            String oldSiteRoot = cms.getRequestContext().getSiteRoot();
099            try {
100                cms.getRequestContext().setSiteRoot(siteRoot);
101                sitePath = cms.getRequestContext().removeSiteRoot(path);
102            } finally {
103                cms.getRequestContext().setSiteRoot(oldSiteRoot);
104            }
105            CmsRewriteAliasMatcher rewriteAliases = OpenCms.getAliasManager().getRewriteAliasMatcher(cms, siteRoot);
106            CmsRewriteAliasMatcher.RewriteResult rewriteResult = rewriteAliases.match(sitePath);
107            if ((rewriteResult != null) && (res != null)) {
108                String link = OpenCms.getLinkManager().substituteLink(cms, rewriteResult.getNewPath());
109                if (rewriteResult.getAlias().getMode().isRedirect()) {
110                    redirectToTarget(
111                        req,
112                        res,
113                        link,
114                        rewriteResult.getAlias().getMode() == CmsAliasMode.permanentRedirect);
115                } else {
116                    cms.getRequestContext().setUri(rewriteResult.getNewPath());
117                }
118                return null;
119            }
120            List<CmsAlias> aliases = OpenCms.getAliasManager().getAliasesForPath(cms, siteRoot, sitePath);
121            assert aliases.size() < 2;
122            if (aliases.size() == 1) {
123                CmsAlias alias = aliases.get(0);
124                CmsResource aliasTarget = cms.readResource(alias.getStructureId());
125
126                if (alias.isRedirect()) {
127                    String link = OpenCms.getLinkManager().substituteLink(cms, aliasTarget);
128                    boolean isPermanent = alias.isPermanentRedirect();
129                    // response may be null if we're coming from the locale manager
130                    redirectToTarget(req, res, link, isPermanent);
131                } else {
132                    // not a redirect, just proceed with the aliased resource
133                    cms.getRequestContext().setUri(cms.getSitePath(aliasTarget));
134                    return aliasTarget;
135                }
136            }
137        } catch (CmsPermissionViolationException e) {
138            // trigger the permission denied handler
139            throw e;
140        } catch (CmsResourceInitException e) {
141            // just rethrow so the catch(Throwable e) code isn't executed
142            throw e;
143        } catch (Throwable e) {
144            String uri = cms.getRequestContext().getUri();
145            CmsMessageContainer msg = org.opencms.ade.detailpage.Messages.get().container(
146                org.opencms.ade.detailpage.Messages.ERR_RESCOURCE_NOT_FOUND_1,
147                uri);
148            LOG.error(e.getLocalizedMessage(), e);
149            throw new CmsResourceInitException(msg, e);
150        }
151
152        return null;
153    }
154
155    /**
156     * Helper method for sending a redirect to a new URI.<p>
157     *
158     * @param req the current request
159     * @param res the current response
160     * @param link the redirect target
161     * @param isPermanent if true, sends a 'moved permanently' redirect
162     *
163     * @throws IOException
164     * @throws CmsResourceInitException
165     */
166    private void redirectToTarget(HttpServletRequest req, HttpServletResponse res, String link, boolean isPermanent)
167    throws IOException, CmsResourceInitException {
168
169        CmsResourceInitException resInitException = new CmsResourceInitException(getClass());
170        if (res != null) {
171            // preserve request parameters for the redirect
172            String query = req.getQueryString();
173            if (query != null) {
174                link += "?" + query;
175            }
176            // disable 404 handler
177            resInitException.setClearErrors(true);
178            if (isPermanent) {
179                res.setStatus(HttpServletResponse.SC_MOVED_PERMANENTLY);
180                res.setHeader("Location", link);
181            } else {
182                res.sendRedirect(link);
183            }
184        }
185        throw resInitException;
186    }
187
188}