/*
* eXist Open Source Native XML Database
* Copyright (C) 2001-2016 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.xquery.update;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.exist.EXistException;
import org.exist.collections.triggers.TriggerException;
import org.exist.dom.persistent.AttrImpl;
import org.exist.dom.persistent.DocumentImpl;
import org.exist.dom.persistent.ElementImpl;
import org.exist.dom.NodeListImpl;
import org.exist.dom.persistent.StoredNode;
import org.exist.dom.persistent.TextImpl;
import org.exist.security.Permission;
import org.exist.security.PermissionDeniedException;
import org.exist.storage.NotificationService;
import org.exist.storage.UpdateListener;
import org.exist.storage.txn.Txn;
import org.exist.util.LockException;
import org.exist.xquery.Dependency;
import org.exist.xquery.Expression;
import org.exist.xquery.Profiler;
import org.exist.xquery.XPathException;
import org.exist.xquery.XPathUtil;
import org.exist.xquery.XQueryContext;
import org.exist.xquery.util.Error;
import org.exist.xquery.util.ExpressionDumper;
import org.exist.xquery.util.Messages;
import org.exist.xquery.value.Item;
import org.exist.xquery.value.NodeValue;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.SequenceIterator;
import org.exist.xquery.value.StringValue;
import org.exist.xquery.value.Type;
import org.exist.xquery.value.ValueSequence;
import org.w3c.dom.Node;
/**
* @author wolf
*
*/
public class Update extends Modification {
private final static Logger LOG = LogManager.getLogger(Update.class);
public Update(XQueryContext context, Expression select, Expression value) {
super(context, select, value);
}
/* (non-Javadoc)
* @see org.exist.xquery.AbstractExpression#eval(org.exist.xquery.value.Sequence, org.exist.xquery.value.Item)
*/
public Sequence eval(Sequence contextSequence, Item contextItem) throws XPathException {
if (context.getProfiler().isEnabled()) {
context.getProfiler().start(this);
context.getProfiler().message(this, Profiler.DEPENDENCIES, "DEPENDENCIES", Dependency.getDependenciesName(this.getDependencies()));
if (contextSequence != null) {
context.getProfiler().message(this, Profiler.START_SEQUENCES, "CONTEXT SEQUENCE", contextSequence);
}
if (contextItem != null) {
context.getProfiler().message(this, Profiler.START_SEQUENCES, "CONTEXT ITEM", contextItem.toSequence());
}
}
if (contextItem != null) {
contextSequence = contextItem.toSequence();
}
final Sequence contentSeq = value.eval(contextSequence);
if (contentSeq.isEmpty()) {
throw new XPathException(this, Messages.getMessage(Error.UPDATE_EMPTY_CONTENT));
}
final Sequence inSeq = select.eval(contextSequence);
//START trap Update failure
/* If we try and Update a node at an invalid location,
* trap the error in a context variable,
* this is then accessible from xquery via. the context extension module - deliriumsky
* TODO: This trapping could be expanded further - basically where XPathException is thrown from thiss class
* TODO: Maybe we could provide more detailed messages in the trap, e.g. couldnt update node `xyz` into `abc` becuase... this would be nicer for the end user of the xquery application
*/
if (!Type.subTypeOf(inSeq.getItemType(), Type.NODE))
{
//Indicate the failure to perform this update by adding it to the sequence in the context variable XQueryContext.XQUERY_CONTEXTVAR_XQUERY_UPDATE_ERROR
ValueSequence prevUpdateErrors = null;
final XPathException xpe = new XPathException(this, Messages.getMessage(Error.UPDATE_SELECT_TYPE));
final Object ctxVarObj = context.getXQueryContextVar(XQueryContext.XQUERY_CONTEXTVAR_XQUERY_UPDATE_ERROR);
if(ctxVarObj == null) {
prevUpdateErrors = new ValueSequence();
} else {
prevUpdateErrors = (ValueSequence)XPathUtil.javaObjectToXPath(ctxVarObj, context);
}
prevUpdateErrors.add(new StringValue(xpe.getMessage()));
context.setXQueryContextVar(XQueryContext.XQUERY_CONTEXTVAR_XQUERY_UPDATE_ERROR, prevUpdateErrors);
if(!inSeq.isEmpty()) {
//TODO: should we trap this instead of throwing an exception - deliriumsky?
throw xpe;
}
}
//END trap Update failure
if (!inSeq.isEmpty()) {
context.pushInScopeNamespaces();
//start a transaction
try (final Txn transaction = getTransaction()) {
final NotificationService notifier = context.getBroker().getBrokerPool().getNotificationService();
final StoredNode ql[] = selectAndLock(transaction, inSeq);
TextImpl text;
AttrImpl attribute;
ElementImpl parent;
for (final StoredNode node : ql) {
final DocumentImpl doc = node.getOwnerDocument();
if (!doc.getPermissions().validate(context.getSubject(),
Permission.WRITE)) {
throw new XPathException(this, "User '" + context.getSubject().getName() + "' does not have permission to write to the document '" + doc.getDocumentURI() + "'!");
}
//update the document
switch (node.getNodeType()) {
case Node.ELEMENT_NODE:
final NodeListImpl content = new NodeListImpl();
for (final SequenceIterator j = contentSeq.iterate(); j.hasNext(); ) {
final Item next = j.nextItem();
if (Type.subTypeOf(next.getType(), Type.NODE)) {
content.add(((NodeValue) next).getNode());
} else {
text = new TextImpl(next.getStringValue());
content.add(text);
}
}
((ElementImpl) node).update(transaction, content);
break;
case Node.TEXT_NODE:
parent = (ElementImpl) node.getParentNode();
text = new TextImpl(contentSeq.getStringValue());
text.setOwnerDocument(doc);
parent.updateChild(transaction, node, text);
break;
case Node.ATTRIBUTE_NODE:
parent = (ElementImpl) node.getParentNode();
if (parent == null) {
LOG.warn("parent node not found for " + node.getNodeId());
break;
}
final AttrImpl attr = (AttrImpl) node;
attribute = new AttrImpl(attr.getQName(), contentSeq.getStringValue(), context.getBroker().getBrokerPool().getSymbols());
attribute.setOwnerDocument(doc);
parent.updateChild(transaction, node, attribute);
break;
default:
throw new XPathException(this, "unsupported node-type");
}
doc.getMetadata().setLastModified(System.currentTimeMillis());
modifiedDocuments.add(doc);
context.getBroker().storeXMLResource(transaction, doc);
notifier.notifyUpdate(doc, UpdateListener.UPDATE);
}
finishTriggers(transaction);
//commit the transaction
transaction.commit();
} catch (final LockException | PermissionDeniedException | EXistException | TriggerException e) {
throw new XPathException(this, e.getMessage(), e);
} finally {
unlockDocuments();
context.popInScopeNamespaces();
}
}
if (context.getProfiler().isEnabled()) {
context.getProfiler().end(this, "", Sequence.EMPTY_SEQUENCE);
}
return Sequence.EMPTY_SEQUENCE;
}
/* (non-Javadoc)
* @see org.exist.xquery.Expression#dump(org.exist.xquery.util.ExpressionDumper)
*/
public void dump(ExpressionDumper dumper) {
dumper.display("update value").nl();
dumper.startIndent();
select.dump(dumper);
dumper.nl().endIndent().display("with").nl().startIndent();
value.dump(dumper);
dumper.nl().endIndent();
}
public String toString() {
return "update value" + select.toString() + " with " + value.toString();
}
}