/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.jackrabbit.webdav.version.report;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.jackrabbit.webdav.DavResource;
import org.apache.jackrabbit.webdav.DavException;
import org.apache.jackrabbit.webdav.DavServletResponse;
import org.apache.jackrabbit.webdav.DavConstants;
import org.apache.jackrabbit.webdav.DavResourceLocator;
import org.apache.jackrabbit.webdav.property.HrefProperty;
import org.apache.jackrabbit.webdav.xml.DomUtil;
import org.apache.jackrabbit.webdav.version.VersionHistoryResource;
import org.apache.jackrabbit.webdav.version.ActivityResource;
import org.apache.jackrabbit.webdav.version.DeltaVConstants;
import org.apache.jackrabbit.webdav.version.VersionResource;
import org.w3c.dom.Element;
import org.w3c.dom.Document;
import java.util.List;
/**
* <code>LatestActivityVersionReport</code> is applied to a version history to
* identify the latest version that is selected from that version history by a
* given activity.
*/
public class LatestActivityVersionReport implements Report {
private static Logger log = LoggerFactory.getLogger(LatestActivityVersionReport.class);
private static final String XML_LATEST_ACTIVITY_VERSION = "latest-activity-version";
private static final String XML_LATEST_ACTIVITY_VERSION_REPORT = "latest-activity-version-report";
public static final ReportType LATEST_ACTIVITY_VERSION = ReportType.register(XML_LATEST_ACTIVITY_VERSION, DeltaVConstants.NAMESPACE, LatestActivityVersionReport.class);
private VersionHistoryResource vhResource;
private DavResource activity;
/**
* Returns {@link #LATEST_ACTIVITY_VERSION}.
*
* @see Report#getType()
*/
public ReportType getType() {
return LATEST_ACTIVITY_VERSION;
}
/**
* Always returns <code>false</code>.
*
* @return false
* @see Report#isMultiStatusReport()
*/
public boolean isMultiStatusReport() {
return false;
}
/**
* Check all the preconditions for this report.
*
* @throws DavException if a precondition is not met.
* @see Report#init(DavResource, ReportInfo)
*/
public void init(DavResource resource, ReportInfo info) throws DavException {
// validate info
if (!getType().isRequestedReportType(info)) {
throw new DavException(DavServletResponse.SC_BAD_REQUEST, "DAV:latest-activity-version element expected.");
}
// make sure the report is applied to a vh-resource
if (resource != null && (resource instanceof VersionHistoryResource)) {
vhResource = (VersionHistoryResource) resource;
} else {
throw new DavException(DavServletResponse.SC_BAD_REQUEST, "DAV:latest-activity-version report can only be created for a version history resource.");
}
// make sure the DAV:href element inside the request body points to
// an activity resource (precondition for this report).
String activityHref = DomUtil.getText(info.getContentElement(DavConstants.XML_HREF, DavConstants.NAMESPACE));
DavResourceLocator vhLocator = resource.getLocator();
DavResourceLocator activityLocator = vhLocator.getFactory().createResourceLocator(vhLocator.getPrefix(), activityHref);
activity = resource.getFactory().createResource(activityLocator, resource.getSession());
if (!(activity instanceof ActivityResource)) {
throw new DavException(DavServletResponse.SC_BAD_REQUEST, "DAV:latest-activity-version report: The DAV:href in the request body MUST identify an activity.");
}
}
/**
*
* @see org.apache.jackrabbit.webdav.xml.XmlSerializable#toXml(Document)
*/
public Element toXml(Document document) {
String latestVersionHref = getLatestVersionHref();
Element el = DomUtil.createElement(document, XML_LATEST_ACTIVITY_VERSION_REPORT, DeltaVConstants.NAMESPACE);
el.appendChild(DomUtil.hrefToXml(latestVersionHref, document));
return el;
}
/**
* The latest-version-href MUST identify the version of the given
* version history that is a member of the DAV:activity-version-set of the
* given activity and has no descendant that is a member of the
* DAV:activity-version-set of that activity.
*
* @return href of the latest version or ""
*/
private String getLatestVersionHref() {
String latestVersionHref = ""; // not found (TODO: check if this valid according to the RFC)
try {
List<String> versionHrefs = new HrefProperty(activity.getProperty(ActivityResource.ACTIVITY_VERSION_SET)).getHrefs();
for (VersionResource vr : vhResource.getVersions()) {
String href = vr.getHref();
if (versionHrefs.contains(href)) {
if ("".equals(latestVersionHref)) {
// shortcut
latestVersionHref = href;
} else {
// if this vr is a descendant of the one already found, set latestVersion again
List<String> predecessors = new HrefProperty(vr.getProperty(VersionResource.PREDECESSOR_SET)).getHrefs();
if (predecessors.contains(latestVersionHref)) {
// version is a descendant of the vr identified by latestVersionHref
latestVersionHref = href;
} // else: version is predecessor -> nothing to do.
}
}
}
} catch (DavException e) {
log.error("Unexpected error while retrieving href of latest version.", e);
}
return latestVersionHref;
}
}