/*
* eXist Open Source Native XML Database
* Copyright (C) 2014 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
*/
package org.exist.collections.triggers;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.apache.commons.lang3.StringUtils;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.exist.collections.Collection;
import org.exist.dom.persistent.DocumentImpl;
import org.exist.security.Permission;
import org.exist.security.PermissionDeniedException;
import org.exist.security.SecurityManager;
import org.exist.source.Source;
import org.exist.source.SourceFactory;
import org.exist.storage.DBBroker;
import org.exist.storage.StartupTrigger;
import org.exist.storage.lock.Lock.LockMode;
import org.exist.storage.txn.TransactionManager;
import org.exist.storage.txn.Txn;
import org.exist.xmldb.XmldbURI;
import org.exist.xquery.CompiledXQuery;
import org.exist.xquery.XQuery;
import org.exist.xquery.XQueryContext;
import org.exist.xquery.value.Sequence;
/**
* Startup Trigger to fire XQuery scripts during database startup.
*
* Load scripts into /db/system/autostart as DBA.
*
* <pre>
* {@code
* <startup>
* <triggers>
* <trigger class="org.exist.collections.triggers.XQueryStartupTrigger"/>
* </triggers>
* </startup>
* }
* </pre>
*
* Due to security reasons individual scripts cannot be specified anymore. The permissions were not checked per file.
*
* <pre>
* {@code
* <parameter name="xquery" value="/db/script1.xq"/>
* <parameter name="xquery" value="/db/script2.xq"/>
* }
* </pre>
*
* @author Dannes Wessels
*/
public class XQueryStartupTrigger implements StartupTrigger {
protected final static Logger LOG = LogManager.getLogger(XQueryStartupTrigger.class);
private static final String XQUERY = "xquery";
private static final String AUTOSTART_COLLECTION = "/db/system/autostart";
private static final String[] XQUERY_EXTENSIONS = {".xq", ".xquery", ".xqy"};
private static final String REQUIRED_MIMETYPE = "application/xquery";
@Override
public void execute(DBBroker broker, Map<String, List<? extends Object>> params) {
LOG.info("Starting Startup Trigger for stored XQueries");
for (String path : getScriptsInStartupCollection(broker)) {
executeQuery(broker, path);
}
// for (String path : getParameters(params)) {
// executeQuery(broker, path);
// }
}
/**
* List all xquery scripts in /db/system/autostart
*
* @param broker The exist-db broker
* @return List of xquery scripts
*/
private List<String> getScriptsInStartupCollection(DBBroker broker) {
// Return values
List<String> paths = new ArrayList<>();
XmldbURI uri = XmldbURI.create(AUTOSTART_COLLECTION);
Collection collection = null;
try {
collection = broker.openCollection(uri, LockMode.READ_LOCK);
if (collection == null) {
LOG.debug(String.format("Collection '%s' not found.", AUTOSTART_COLLECTION));
createAutostartCollection(broker);
} else {
LOG.debug(String.format("Scanning collection '%s'.", AUTOSTART_COLLECTION));
if (isPermissionsOK(collection)) {
Iterator<DocumentImpl> documents = collection.iteratorNoLock(broker);
while (documents.hasNext()) {
DocumentImpl document = documents.next();
String docPath = document.getURI().toString();
if (isPermissionsOK(document)) {
if (StringUtils.endsWithAny(docPath, XQUERY_EXTENSIONS)) {
paths.add(XmldbURI.EMBEDDED_SERVER_URI_PREFIX + docPath);
} else {
LOG.error(String.format("Skipped document '%s', not an xquery script.", docPath));
}
} else {
LOG.error(String.format("Document %s should be owned by DBA, mode %s, mimetype %s",
docPath, Permission.DEFAULT_SYSTEM_SECURITY_COLLECTION_PERM, REQUIRED_MIMETYPE));
}
}
} else {
LOG.error(String.format("Collection %s should be owned by SYSTEM/DBA, mode %s.", AUTOSTART_COLLECTION,
Permission.DEFAULT_SYSTEM_SECURITY_COLLECTION_PERM));
}
}
LOG.debug(String.format("Found %s xquery scripts in '%s'.", paths.size(), AUTOSTART_COLLECTION));
} catch (PermissionDeniedException ex) {
LOG.error(ex.getMessage());
} finally {
// Clean up resources
if (collection != null) {
collection.release(LockMode.READ_LOCK);
}
}
return paths;
}
/**
* Verify that the permissions for a collection are SYSTEM/DBA/770
*
* @param collection The collection
* @return TRUE if the conditions are met, else FALSE
*/
private boolean isPermissionsOK(Collection collection) {
Permission perms = collection.getPermissions();
return (perms.getOwner().getName().equals(SecurityManager.SYSTEM)
&& perms.getGroup().getName().equals(SecurityManager.DBA_GROUP)
&& perms.getMode() == Permission.DEFAULT_SYSTEM_SECURITY_COLLECTION_PERM);
}
/**
* Verify that the owner of the document is DBA, the document is owned by the DBA group and that the permissions are
* set 0770, and the mimetype is set application/xquery.
*
* @param collection The document
* @return TRUE if the conditions are met, else FALSE
*/
private boolean isPermissionsOK(DocumentImpl document) {
Permission perms = document.getPermissions();
return (perms.getOwner().hasDbaRole()
&& perms.getGroup().getName().equals(SecurityManager.DBA_GROUP)
&& perms.getMode() == Permission.DEFAULT_SYSTEM_SECURITY_COLLECTION_PERM
&& document.getMetadata().getMimeType().equals(REQUIRED_MIMETYPE));
}
/**
* Get all XQuery paths from provided parameters in conf.xml
*/
private List<String> getParameters(Map<String, List<? extends Object>> params) {
// Return values
List<String> paths = new ArrayList<>();
// The complete data map
Set<Map.Entry<String, List<? extends Object>>> data = params.entrySet();
// Iterate over all entries
for (Map.Entry<String, List<? extends Object>> entry : data) {
// only the 'xpath' parameter is used.
if (XQUERY.equals(entry.getKey())) {
// Iterate over all values (object lists)
List<? extends Object> list = entry.getValue();
for (Object o : list) {
if (o instanceof String) {
String value = (String) o;
if (value.startsWith("/")) {
// Rewrite to URL in database
value = XmldbURI.EMBEDDED_SERVER_URI_PREFIX + value;
// Prevent double entries
if (!paths.contains(value)) {
paths.add(value);
}
} else {
LOG.error(String.format("Path '%s' should start with a '/'", value));
}
}
}
}
}
LOG.debug(String.format("Found %s 'xquery' entries.", paths.size()));
return paths;
}
/**
* Execute xquery on path
*
* @param broker eXist database broker
* @param path path to query, formatted as xmldb:exist:///db/...
*/
private void executeQuery(DBBroker broker, String path) {
XQueryContext context = null;
try {
// Get path to xquery
Source source = SourceFactory.getSource(broker, null, path, false);
if (source == null) {
LOG.info(String.format("No Xquery found at '%s'", path));
} else {
// Setup xquery service
XQuery service = broker.getBrokerPool().getXQueryService();
context = new XQueryContext(broker.getBrokerPool());
// Allow use of modules with relative paths
String moduleLoadPath = StringUtils.substringBeforeLast(path, "/");
context.setModuleLoadPath(moduleLoadPath);
// Compile query
CompiledXQuery compiledQuery = service.compile(broker, context, source);
LOG.info(String.format("Starting Xquery at '%s'", path));
// Finish preparation
context.prepareForExecution();
// Execute
Sequence result = service.execute(broker, compiledQuery, null);
// Log results
LOG.info(String.format("Result xquery: '%s'", result.getStringValue()));
}
} catch (Throwable t) {
// Dirty, catch it all
LOG.error(String.format("An error occured during preparation/execution of the xquery script %s: %s", path, t.getMessage()), t);
} finally {
if (context != null) {
context.runCleanupTasks();
}
}
}
/**
* Create autostart collection when not existent
*
* @param broker The exist-db broker
*/
private void createAutostartCollection(DBBroker broker) {
LOG.info(String.format("Creating %s", AUTOSTART_COLLECTION));
final TransactionManager txnManager = broker.getBrokerPool().getTransactionManager();
try(final Txn txn = txnManager.beginTransaction()) {
XmldbURI newCollection = XmldbURI.create(AUTOSTART_COLLECTION, true);
// Create collection
Collection created = broker.getOrCreateCollection(txn, newCollection);
// Set ownership
Permission perms = created.getPermissions();
perms.setOwner(broker.getBrokerPool().getSecurityManager().getSystemSubject());
perms.setGroup(broker.getBrokerPool().getSecurityManager().getDBAGroup());
perms.setMode(Permission.DEFAULT_SYSTEM_SECURITY_COLLECTION_PERM);
broker.saveCollection(txn, created);
broker.flush();
// Commit change
txnManager.commit(txn);
if (LOG.isDebugEnabled()) {
LOG.debug("Finished creation of collection");
}
} catch (Throwable ex) {
LOG.error(ex);
}
}
}