Java tutorial
/** * This file Copyright (c) 2003-2012 Magnolia International * Ltd. (http://www.magnolia-cms.com). All rights reserved. * * * This file is dual-licensed under both the Magnolia * Network Agreement and the GNU General Public License. * You may elect to use one or the other of these licenses. * * This file is distributed in the hope that it will be * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the * implied warranty of MERCHANTABILITY or FITNESS FOR A * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT. * Redistribution, except as permitted by whichever of the GPL * or MNA you select, is prohibited. * * 1. For the GPL license (GPL), you can redistribute and/or * modify this file under the terms of the GNU General * Public License, Version 3, as published by the Free Software * Foundation. You should have received a copy of the GNU * General Public License, Version 3 along with this program; * if not, write to the Free Software Foundation, Inc., 51 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * 2. For the Magnolia Network Agreement (MNA), this file * and the accompanying materials are made available under the * terms of the MNA which accompanies this distribution, and * is available at http://www.magnolia-cms.com/mna.html * * Any modifications to this file must keep this entire header * intact. * */ package info.magnolia.cms.core.version; import info.magnolia.cms.core.Content; import info.magnolia.cms.core.ItemType; import info.magnolia.cms.core.Path; import info.magnolia.cms.security.JCRSessionOp; import info.magnolia.cms.security.PermissionUtil; import info.magnolia.cms.util.Rule; import info.magnolia.context.MgnlContext; import info.magnolia.jcr.predicate.RuleBasedNodePredicate; import info.magnolia.jcr.util.NodeUtil; import info.magnolia.jcr.util.VersionUtil; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.ObjectInput; import java.io.ObjectInputStream; import java.io.ObjectOutput; import java.io.ObjectOutputStream; import java.util.ArrayList; import java.util.List; import javax.jcr.ItemNotFoundException; import javax.jcr.LoginException; import javax.jcr.Node; import javax.jcr.NodeIterator; import javax.jcr.PathNotFoundException; import javax.jcr.RepositoryException; import javax.jcr.Session; import javax.jcr.UnsupportedRepositoryOperationException; import javax.jcr.Value; import javax.jcr.nodetype.NodeType; import javax.jcr.version.Version; import javax.jcr.version.VersionException; import javax.jcr.version.VersionHistory; import javax.jcr.version.VersionIterator; import org.apache.commons.codec.binary.Base64; import org.apache.commons.io.IOUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * This version manager uses an extra workspace to manage the versions. The * workspace maintains a flat hierarchy. The content is then finally versioned * using JCR versioning which also copies the sub-nodes. * * The mix:versionable is only added on the top level nodes. * * @version $Id$ */ public abstract class BaseVersionManager { /** * Name of the workspace. */ public static final String VERSION_WORKSPACE = "mgnlVersion"; /** * Node which contains stubs for referenced nodes. We have to copy them to the workspace as well. */ public static final String TMP_REFERENCED_NODES = "mgnl:tmpReferencedNodes"; /** * Sub-node containing the data used for the version/restore process. */ protected static final String SYSTEM_NODE = "mgnl:versionMetaData"; /** * Property name for collection rule. The rule defines which sub-nodes belong to a node: page and paragraphs. */ public static final String PROPERTY_RULE = "Rule"; /** * JCR version store root. */ protected static final String ROOT_VERSION = "jcr:rootVersion"; private static Logger log = LoggerFactory.getLogger(BaseVersionManager.class); /** * Create structure needed for version store workspace. * @throws RepositoryException if unable to create magnolia system structure */ protected void createInitialStructure() throws RepositoryException { MgnlContext.doInSystemContext(new JCRSessionOp<Void>(VERSION_WORKSPACE) { @Override public Void exec(Session session) throws RepositoryException { try { Node tmp = session.getNode("/" + VersionManager.TMP_REFERENCED_NODES); // remove nodes if they are no longer referenced within this workspace NodeIterator children = tmp.getNodes(); while (children.hasNext()) { Node child = children.nextNode(); if (child.getReferences().getSize() < 1) { child.remove(); } } } catch (PathNotFoundException e) { session.getRootNode().addNode(VersionManager.TMP_REFERENCED_NODES, ItemType.SYSTEM.getSystemName()); } session.save(); return null; } }); } /** * Add version of the specified node and all child nodes while ignoring the same node type. * @param node to be versioned * @return newly created version node * @throws UnsupportedOperationException if repository implementation does not support Versions API * @throws javax.jcr.RepositoryException if any repository error occurs */ public synchronized Version addVersion(Node node) throws UnsupportedRepositoryOperationException, RepositoryException { // Rule rule = new Rule(new String[] {node.getNodeType().getName(), ItemType.SYSTEM.getSystemName()}); Rule rule = new Rule(VersionUtil.getNodeTypeName(node) + "," + ItemType.SYSTEM.getSystemName(), ","); rule.reverse(); return this.addVersion(node, rule); } /** * Add version of the specified node and all child nodes while ignoring the same node type. * @param node to be versioned * @return newly created version node * @throws UnsupportedOperationException if repository implementation does not support Versions API * @throws javax.jcr.RepositoryException if any repository error occurs */ public synchronized Version addVersion(final Node node, final Rule rule) throws UnsupportedRepositoryOperationException, RepositoryException { final String userName = getSafelyUsersNameFromMgnlContenxt(); Version version = MgnlContext .doInSystemContext(new JCRSessionOp<Version>(node.getSession().getWorkspace().getName()) { @Override public Version exec(Session session) throws RepositoryException { try { return createVersion(session.getNodeByIdentifier(node.getIdentifier()), rule, userName); } catch (RepositoryException re) { // since add version is synchronized on a singleton object, its safe to revert all changes made in // the session attached to workspace - mgnlVersion log.error( "failed to copy versionable node to version store, reverting all changes made in this session"); getSession().refresh(false); throw re; } } }); return version; } /** * Create version of the specified node and all child nodes based on the given <code>Rule</code>. * @param node to be versioned * @param rule * @return newly created version node * @throws UnsupportedOperationException if repository implementation does not support Versions API * @throws javax.jcr.RepositoryException if any repository error occurs * @deprecated since 4.5 use {@link #createVersion(Node, Rule)} instead */ @Deprecated protected Version createVersion(Content node, Rule rule) throws UnsupportedRepositoryOperationException, RepositoryException { return createVersion(node.getJCRNode(), rule, getSafelyUsersNameFromMgnlContenxt()); } private String getSafelyUsersNameFromMgnlContenxt() { String userName = ""; if (MgnlContext.getUser() != null) { userName = MgnlContext.getUser().getName(); } return userName; } /** * Create version of the specified node and all child nodes based on the given <code>Rule</code>. * @param node to be versioned * @param rule * @param userName * @return newly created version node * @throws UnsupportedOperationException if repository implementation does not support Versions API * @throws javax.jcr.RepositoryException if any repository error occurs */ protected Version createVersion(Node node, Rule rule, String userName) throws UnsupportedRepositoryOperationException, RepositoryException { if (isInvalidMaxVersions()) { log.debug("Ignore create version, MaxVersionIndex < 1"); log.debug("Returning root version of the source node"); return node.getVersionHistory().getRootVersion(); } CopyUtil.getInstance().copyToversion(node, new RuleBasedNodePredicate(rule)); Node versionedNode = this.getVersionedNode(node); checkAndAddMixin(versionedNode); Node systemInfo = this.getSystemNode(versionedNode); // add serialized rule which was used to create this version ByteArrayOutputStream out = new ByteArrayOutputStream(); try { ObjectOutput objectOut = new ObjectOutputStream(out); objectOut.writeObject(rule); objectOut.flush(); objectOut.close(); // PROPERTY_RULE is not a part of MetaData to allow versioning of node types which does NOT support MetaData systemInfo.setProperty(PROPERTY_RULE, new String(Base64.encodeBase64(out.toByteArray()))); } catch (IOException e) { throw new RepositoryException("Unable to add serialized Rule to the versioned content"); } // add all system properties for this version systemInfo.setProperty(ContentVersion.VERSION_USER, userName); systemInfo.setProperty(ContentVersion.NAME, node.getName()); versionedNode.save(); // add version Version newVersion = versionedNode.checkin(); versionedNode.checkout(); try { this.setMaxVersionHistory(versionedNode); } catch (RepositoryException re) { log.error("Failed to limit version history to the maximum configured", re); log.error("New version has already been created"); } return newVersion; } /** * Check if version index is set to negative number. */ public abstract boolean isInvalidMaxVersions(); /** * Get node from version store. */ public synchronized Node getVersionedNode(Node node) throws RepositoryException { return getVersionedNode(node.getIdentifier()); } /** * Get node from version store. */ protected Node getVersionedNode(String uuid) throws RepositoryException { try { return getSession().getNodeByIdentifier(uuid); } catch (ItemNotFoundException e) { // node is not versioned yet return null; } } /** * Set version history to max version possible. * @throws RepositoryException if failed to get VersionHistory or fail to remove */ public abstract void setMaxVersionHistory(Node node) throws RepositoryException; /** * Get history of this node as recorded in the version store. * @param node * @return version history of the given node * @throws UnsupportedOperationException if repository implementation does not support Versions API * @throws javax.jcr.RepositoryException if any repository error occurs */ public synchronized VersionHistory getVersionHistory(Node node) throws UnsupportedRepositoryOperationException, RepositoryException { try { Node versionedNode = this.getVersionedNode(node); if (versionedNode == null) { // node does not exist in version store so no version history log.debug("No VersionHistory found for {} node.", node); return null; } return versionedNode.getVersionHistory(); } catch (UnsupportedRepositoryOperationException e) { log.debug("Node {} is not versionable.", node); // node is not versionable or underlying repo doesn't support versioning. return null; } } /** * /** Get named version. * * @throws UnsupportedOperationException * if repository implementation does not support Versions API * @throws javax.jcr.RepositoryException * if any repository error occurs */ public synchronized Version getVersion(Node node, String name) throws UnsupportedRepositoryOperationException, RepositoryException { VersionHistory history = this.getVersionHistory(node); if (history != null) { return new VersionedNode(history.getVersion(name), node); } log.error("Node " + node.getPath() + " was never versioned"); return null; } /** * Returns the current base version of given node. * @throws UnsupportedRepositoryOperationException * @throws RepositoryException */ public Version getBaseVersion(Node node) throws UnsupportedOperationException, RepositoryException { Node versionedNode = this.getVersionedNode(node); if (versionedNode != null) { return versionedNode.getBaseVersion(); } throw new RepositoryException("Node " + node.getPath() + " was never versioned"); } /** * Get all versions. * @param node * @return Version iterator retrieved from version history * @throws UnsupportedOperationException if repository implementation does not support Versions API * @throws javax.jcr.RepositoryException if any repository error occurs */ public synchronized VersionIterator getAllVersions(Node node) throws UnsupportedRepositoryOperationException, RepositoryException { Node versionedNode = this.getVersionedNode(node); if (versionedNode == null) { // node does not exist in version store so no versions return null; } return versionedNode.getVersionHistory().getAllVersions(); } /** * Restore specified version. * @param node to be restored * @param version to be used * @param removeExisting * @throws javax.jcr.version.VersionException if the specified <code>versionName</code> does not exist in this * node's version history * @throws javax.jcr.RepositoryException if an error occurs * @throws javax.jcr.version.VersionException * @deprecated since 4.5 use {@link #restore(Node, Version, boolean)} instead */ @Deprecated public synchronized void restore(Content node, Version version, boolean removeExisting) throws VersionException, UnsupportedRepositoryOperationException, RepositoryException { restore(node.getJCRNode(), version, removeExisting); } /** * Restore specified version. * @param node to be restored * @param version to be used * @param removeExisting * @throws javax.jcr.version.VersionException if the specified <code>versionName</code> does not exist in this * node's version history * @throws javax.jcr.RepositoryException if an error occurs * @throws javax.jcr.version.VersionException */ public synchronized void restore(final Node node, Version version, boolean removeExisting) throws VersionException, UnsupportedRepositoryOperationException, RepositoryException { // FYI: restore is done in SC!!! Check permissions manually PermissionUtil.verifyIsGrantedOrThrowException(node.getSession(), node.getPath(), Session.ACTION_SET_PROPERTY + "," + Session.ACTION_REMOVE + "," + Session.ACTION_ADD_NODE); // get the cloned node from version store final Node versionedNode = this.getVersionedNode(node); final Version unwrappedVersion; if (version instanceof VersionedNode) { unwrappedVersion = ((VersionedNode) version).unwrap(); } else { unwrappedVersion = version; } versionedNode.restore(unwrappedVersion, removeExisting); versionedNode.checkout(); MgnlContext.doInSystemContext(new JCRSessionOp<Void>(versionedNode.getSession().getWorkspace().getName()) { @Override public Void exec(Session session) throws RepositoryException { //mixins are NOT restored automatically List<String> mixins = new ArrayList<String>(); for (Value v : unwrappedVersion.getNode(ItemType.JCR_FROZENNODE).getProperty("jcr:frozenMixinTypes") .getValues()) { mixins.add(v.getString()); } final Node systemVersionedNode = session.getNodeByIdentifier(versionedNode.getUUID()); for (NodeType nt : versionedNode.getMixinNodeTypes()) { if (!mixins.remove(nt.getName())) { systemVersionedNode.removeMixin(nt.getName()); } } for (String mix : mixins) { systemVersionedNode.addMixin(mix); } systemVersionedNode.save(); try { // using system context here is forced by the fact that JR will use same context to also check source (mgnlVersion) repo READ permission and ordinary user has no rights in this workspace Session sysDestinationSession = MgnlContext .getJCRSession(node.getSession().getWorkspace().getName()); log.debug("restoring info:{}:{}", sysDestinationSession.getWorkspace().getName(), node.getPath()); Node destinationNode = sysDestinationSession.getNode(node.getPath()); // if restored, update original node with the restored node and its subtree Rule rule = getUsedFilter(versionedNode); try { CopyUtil.getInstance().copyFromVersion(versionedNode, destinationNode, new RuleBasedNodePredicate(rule)); if (NodeUtil.hasMixin(destinationNode, ItemType.DELETED_NODE_MIXIN)) { destinationNode.removeMixin(ItemType.DELETED_NODE_MIXIN); } destinationNode.save(); // node was updated in system context and we should make sure it is notified of the changes node.refresh(false); } catch (RepositoryException re) { if (log.isDebugEnabled()) { log.debug("error during restore: " + re.getMessage(), re); } else { log.error("failed to restore versioned node, reverting all changes make to this node"); } destinationNode.refresh(false); throw re; } } catch (IOException e) { throw new RepositoryException(e); } catch (ClassNotFoundException e) { throw new RepositoryException(e); } return null; } }); } /** * Removes all versions of the node associated with given UUID. * @throws RepositoryException if fails to remove versioned node from the version store */ public synchronized void removeVersionHistory(final Node node) throws RepositoryException { PermissionUtil.verifyIsGrantedOrThrowException(node.getSession(), Path.getAbsolutePath(node.getPath()), Session.ACTION_ADD_NODE + "," + Session.ACTION_REMOVE + "," + Session.ACTION_SET_PROPERTY); final String uuid = node.getIdentifier(); MgnlContext.doInSystemContext(new JCRSessionOp<Void>(VersionManager.VERSION_WORKSPACE) { @Override public Void exec(Session session) throws RepositoryException { Node node = getVersionedNode(uuid); if (node != null) { if (node.getReferences().getSize() < 1) { // remove node from the version store only if its not referenced node.remove(); } else { // remove all associated versions VersionHistory history = node.getVersionHistory(); VersionIterator versions = history.getAllVersions(); if (versions != null) { // skip root version versions.nextVersion(); while (versions.hasNext()) { history.removeVersion(versions.nextVersion().getName()); } } } } session.save(); return null; } }); } /** * Verifies the existence of the mix:versionable and adds it if not. */ protected void checkAndAddMixin(Node node) throws RepositoryException { if (!node.isNodeType("mix:versionable")) { log.debug("Add mix:versionable"); node.addMixin("mix:versionable"); } } /** * Get Rule used for this version. * @param versionedNode * @throws IOException * @throws ClassNotFoundException * @throws RepositoryException */ protected Rule getUsedFilter(Node versionedNode) throws IOException, ClassNotFoundException, RepositoryException { // if restored, update original node with the restored node and its subtree ByteArrayInputStream inStream = null; try { String ruleString = this.getSystemNode(versionedNode).getProperty(PROPERTY_RULE).getString(); inStream = new ByteArrayInputStream(Base64.decodeBase64(ruleString.getBytes())); ObjectInput objectInput = new ObjectInputStream(inStream); return (Rule) objectInput.readObject(); } catch (IOException e) { throw e; } catch (ClassNotFoundException e) { throw e; } finally { IOUtils.closeQuietly(inStream); } } /** * Get the Magnolia system node created under the given node. * @param node * @throws RepositoryException if failed to create system node */ protected synchronized Node getSystemNode(Node node) throws RepositoryException { if (node.hasNode(SYSTEM_NODE)) { return node.getNode(SYSTEM_NODE); } return node.addNode(SYSTEM_NODE, ItemType.SYSTEM.getSystemName()); } /** * Get version store hierarchy manager. * @throws RepositoryException * @throws LoginException */ protected Session getSession() throws LoginException, RepositoryException { return MgnlContext.getSystemContext().getJCRSession(VersionManager.VERSION_WORKSPACE); } }