/*
* eXist Open Source Native XML Database
* Copyright (C) 2010 The eXist Project
* http://exist-db.org
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* $Id$
*/
package org.exist.webdav;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import com.bradmcevoy.http.Resource;
import com.bradmcevoy.http.ResourceFactory;
import java.io.InputStream;
import java.net.URISyntaxException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.Optional;
import java.util.Properties;
import javax.xml.transform.OutputKeys;
import org.exist.EXistException;
import org.exist.collections.Collection;
import org.exist.dom.persistent.DocumentImpl;
import org.exist.storage.BrokerPool;
import org.exist.storage.DBBroker;
import org.exist.storage.lock.Lock.LockMode;
import org.exist.storage.serializers.EXistOutputKeys;
import org.exist.util.FileUtils;
import org.exist.xmldb.XmldbURI;
/**
* Class for constructing Milton WebDAV framework resource objects .
*
* @author Dannes Wessels (dizzzz_at_exist-db.org)
*/
public class ExistResourceFactory implements ResourceFactory {
private final static Logger LOG = LogManager.getLogger(ExistResourceFactory.class);
private BrokerPool brokerPool = null;
// default output properties for the XML serialization
public final static Properties DEFAULT_WEBDAV_OPTIONS = new Properties();
/** XML serialization options */
private Properties webDavOptions = new Properties();
/**
* Default serialization options
*/
static {
DEFAULT_WEBDAV_OPTIONS.setProperty(OutputKeys.INDENT, "yes");
DEFAULT_WEBDAV_OPTIONS.setProperty(OutputKeys.ENCODING, "UTF-8");
DEFAULT_WEBDAV_OPTIONS.setProperty(OutputKeys.OMIT_XML_DECLARATION, "no");
DEFAULT_WEBDAV_OPTIONS.setProperty(EXistOutputKeys.EXPAND_XINCLUDES, "no");
DEFAULT_WEBDAV_OPTIONS.setProperty(EXistOutputKeys.PROCESS_XSL_PI, "no");
}
private enum ResourceType {
DOCUMENT, COLLECTION, IGNORABLE, NOT_EXISTING
};
/**
* Default constructor. Get access to instance of exist-db broker pool.
*/
public ExistResourceFactory() {
try {
brokerPool = BrokerPool.getInstance();
} catch (EXistException e) {
LOG.error("Unable to initialize WebDAV interface.", e);
}
// Set default values
webDavOptions.putAll(DEFAULT_WEBDAV_OPTIONS);
// load specific options
try {
// Find right file
final Optional<Path> eXistHome = brokerPool.getConfiguration().getExistHome();
final Path config = FileUtils.resolve(eXistHome, "webdav.properties");
// Read from file if existent
if(Files.isReadable(config)) {
LOG.info(String.format("Read WebDAV configuration from %s", config.toAbsolutePath().toString()));
try (final InputStream is = Files.newInputStream(config)) {
webDavOptions.load(is);
}
} else {
LOG.info("Using WebDAV default serialization options.");
}
} catch (Throwable ex) {
LOG.error(ex.getMessage());
}
}
/*
* Construct Resource for path. A Document or Collection resource is returned, NULL if type
* could not be detected.
*/
@Override
public Resource getResource(String host, String path) {
// DWES: work around if no /db is available return nothing.
if (!path.contains("/db")) {
LOG.error("path should at least contain /db");
return null;
}
// Construct path as eXist-db XmldbURI
XmldbURI xmldbUri = null;
try {
// Strip preceding path, all up to /db
path = path.substring(path.indexOf("/db"));
// Strip last slash if available
if (path.endsWith("/")) {
path = path.substring(0, path.lastIndexOf("/"));
}
if(LOG.isDebugEnabled()) {
LOG.debug(String.format("host='%s' path='%s'", host, path));
}
// Create uri inside database
xmldbUri = XmldbURI.xmldbUriFor(path);
} catch (URISyntaxException e) {
LOG.error(String.format("Unable to convert path '%s'into a XmldbURI representation.", path));
return null;
}
// Return appropriate resource
switch (getResourceType(brokerPool, xmldbUri)) {
case DOCUMENT:
MiltonDocument doc = new MiltonDocument(host, xmldbUri, brokerPool);
doc.setConfiguration(webDavOptions);
return doc;
case COLLECTION:
return new MiltonCollection(host, xmldbUri, brokerPool);
case IGNORABLE:
if (LOG.isDebugEnabled()) {
LOG.debug("ignoring file");
}
return null;
case NOT_EXISTING:
if (LOG.isDebugEnabled()) {
LOG.debug(String.format("Resource does not exist: '%s'", xmldbUri));
}
return null;
default:
LOG.error(String.format("Unkown resource type for %s", xmldbUri));
return null;
}
}
/*
* Returns the resource type indicated by the path: either COLLECTION, DOCUMENT or NOT_EXISTING.
*/
private ResourceType getResourceType(BrokerPool brokerPool, XmldbURI xmldbUri) {
Collection collection = null;
DocumentImpl document = null;
ResourceType type = ResourceType.NOT_EXISTING;
// MacOsX finder specific files
String documentSeqment = xmldbUri.lastSegment().toString();
if(documentSeqment.startsWith("._") || documentSeqment.equals(".DS_Store")){
//LOG.debug(String.format("Ignoring MacOSX file '%s'", xmldbUri.lastSegment().toString()));
//return ResourceType.IGNORABLE;
}
// Documents that start with a dot
if(documentSeqment.startsWith(".")){
//LOG.debug(String.format("Ignoring '.' file '%s'", xmldbUri.lastSegment().toString()));
//return ResourceType.IGNORABLE;
}
// Try to read as system user. Note that the actual user is not know
// yet. In MiltonResource the actual authentication and authorization
// is performed.
try(final DBBroker broker = brokerPool.get(Optional.of(brokerPool.getSecurityManager().getSystemSubject()))) {
if(LOG.isDebugEnabled()) {
LOG.debug(String.format("Path: %s", xmldbUri.toString()));
}
// First check if resource is a collection
collection = broker.openCollection(xmldbUri, LockMode.READ_LOCK);
if (collection != null) {
type = ResourceType.COLLECTION;
collection.release(LockMode.READ_LOCK);
collection = null;
} else {
// If it is not a collection, check if it is a document
document = broker.getXMLResource(xmldbUri, LockMode.READ_LOCK);
if (document != null) {
// Document is found
type = ResourceType.DOCUMENT;
document.getUpdateLock().release(LockMode.READ_LOCK);
document = null;
} else {
// No document and no collection.
type = ResourceType.NOT_EXISTING;
}
}
} catch (Exception ex) {
LOG.error(String.format("Error determining nature of resource %s", xmldbUri.toString()), ex);
type = ResourceType.NOT_EXISTING;
} finally {
// Clean-up, just in case
if (collection != null) {
collection.release(LockMode.READ_LOCK);
}
// Clean-up, just in case
if (document != null) {
document.getUpdateLock().release(LockMode.READ_LOCK);
}
}
if(LOG.isDebugEnabled()) {
LOG.debug(String.format("Resource type=%s", type.toString()));
}
return type;
}
}