JMSCatalogModifyEventHandler.java

/* Copyright (c) 2011 GeoSolutions - http://www.geo-solutions.it/.  All rights reserved.
 * This code is licensed under the GPL 2.0 license, available at the root
 * application directory.
 */
package it.geosolutions.geoserver.jms.impl.handlers.catalog;

import it.geosolutions.geoserver.jms.events.ToggleSwitch;
import it.geosolutions.geoserver.jms.impl.utils.BeanUtils;

import java.lang.reflect.InvocationTargetException;
import java.util.List;

import org.geoserver.catalog.Catalog;
import org.geoserver.catalog.CatalogException;
import org.geoserver.catalog.CatalogInfo;
import org.geoserver.catalog.CoverageInfo;
import org.geoserver.catalog.CoverageStoreInfo;
import org.geoserver.catalog.DataStoreInfo;
import org.geoserver.catalog.FeatureTypeInfo;
import org.geoserver.catalog.LayerGroupInfo;
import org.geoserver.catalog.LayerInfo;
import org.geoserver.catalog.MapInfo;
import org.geoserver.catalog.NamespaceInfo;
import org.geoserver.catalog.ResourceInfo;
import org.geoserver.catalog.StoreInfo;
import org.geoserver.catalog.StyleInfo;
import org.geoserver.catalog.WMSLayerInfo;
import org.geoserver.catalog.WMSStoreInfo;
import org.geoserver.catalog.WorkspaceInfo;
import org.geoserver.catalog.event.CatalogEvent;
import org.geoserver.catalog.event.CatalogModifyEvent;

import com.thoughtworks.xstream.XStream;

/**
 * 
 * Handle modify events synchronizing catalog with serialized objects
 * 
 * @author Carlo Cancellieri - carlo.cancellieri@geo-solutions.it
 * 
 */
public class JMSCatalogModifyEventHandler extends JMSCatalogEventHandler {
	
	private final Catalog catalog;
	private final ToggleSwitch producer;

	/**
	 * 
	 * @param catalog
	 * @param xstream
	 * @param clazz
	 * @param producer
	 */
	public JMSCatalogModifyEventHandler(Catalog catalog, XStream xstream,
			Class clazz, ToggleSwitch producer) {
		super(xstream, clazz);
		this.catalog = catalog;
		this.producer = producer;
	}

	@Override
	public boolean synchronize(CatalogEvent event) throws Exception {
		if (event == null) {
			throw new IllegalArgumentException("Incoming object is null");
		}
		try {
			if (event instanceof CatalogModifyEvent) {
				final CatalogModifyEvent modifyEv = ((CatalogModifyEvent) event);

				producer.disable();
				JMSCatalogModifyEventHandler.modify(catalog, modifyEv);

			} else {
				// incoming object not recognized
				if (LOGGER.isLoggable(java.util.logging.Level.SEVERE))
					LOGGER.severe("Unrecognized event type");
				return false;
			}

		} catch (Exception e) {
			if (LOGGER.isLoggable(java.util.logging.Level.SEVERE))
				LOGGER.severe(this.getClass()+" is unable to synchronize the incoming event: "+event);
			throw e;
		} finally {
			// re enable the producer
			producer.enable();
		}
		return true;
	}

	/**
	 * simulate a catalog.save() rebuilding the EventModify proxy object locally
	 * {@link
	 * org.geoserver.catalog.impl.DefaultCatalogFacade.saved(CatalogInfo)}
	 * 
	 * @param catalog
	 * @param modifyEv
	 * @throws IllegalAccessException
	 * @throws InvocationTargetException
	 * @throws NoSuchMethodException
	 * 
	 * TODO synchronization on catalog object
	 */
	protected static void modify(final Catalog catalog,
			CatalogModifyEvent modifyEv) throws IllegalAccessException,
			InvocationTargetException, NoSuchMethodException {

		final CatalogInfo info = modifyEv.getSource();

		// check if name is changed
		String name = getOldName(catalog, modifyEv);

		if (info instanceof LayerGroupInfo) {

			// check if name is changed
			if (name == null) {
				// name is unchanged
				name = ((LayerGroupInfo) info).getName();
			}

			final LayerGroupInfo localObject = catalog
					.getLayerGroupByName(name);

			if (localObject == null) {
				throw new CatalogException("Unable to locate " + info
						+ " named: " + name + " locally.");
			}

			BeanUtils.smartUpdate(localObject, modifyEv.getPropertyNames(),
					modifyEv.getNewValues());
			catalog.save(localObject);

		} else if (info instanceof LayerInfo) {

			// check if name is changed
			if (name == null) {
				// name is unchanged
				name = ((LayerInfo) info).getName();
			}

			final LayerInfo localObject = catalog.getLayerByName(name);

			if (localObject == null) {
				throw new CatalogException("Unable to locate " + info
						+ " named: " + name + " locally.");
			}

			BeanUtils.smartUpdate(localObject, modifyEv.getPropertyNames(),
					modifyEv.getNewValues());
			catalog.save(localObject);

		} else if (info instanceof MapInfo) {

			// check if name is changed
			if (name == null) {
				// name is unchanged
				name = ((MapInfo) info).getName();
			}

			final MapInfo localObject = catalog.getMapByName(name);

			if (localObject == null) {
				throw new CatalogException("Unable to locate " + info
						+ " named: " + name + " locally.");
			}

			BeanUtils.smartUpdate(localObject, modifyEv.getPropertyNames(),
					modifyEv.getNewValues());
			catalog.save(localObject);

		} else if (info instanceof NamespaceInfo) {

			final String uri;
			final Object uriObj = getOldValue(catalog, modifyEv, "uRI");
			if (uriObj != null) {
				uri = uriObj.toString();
			} else {
				// uri is unchanged
				uri = ((NamespaceInfo) info).getURI();
			}
			final NamespaceInfo localObject = catalog.getNamespaceByURI(uri);

			if (localObject == null) {
				throw new CatalogException("Unable to locate " + info
						+ " uri: " + uri + " locally.");
			}

			BeanUtils.smartUpdate(localObject, modifyEv.getPropertyNames(),
					modifyEv.getNewValues());
			catalog.save(localObject);

		} else if (info instanceof StoreInfo) {

			// check if name is changed
			if (name == null) {
				// name is unchanged
				name = ((StoreInfo) info).getName();
			}
			// check if workspace is changed
			final WorkspaceInfo workspace;
			final Object objWorkpsace = getOldValue(catalog, modifyEv,
					"workspace");
			if (objWorkpsace != null) {
				workspace = (WorkspaceInfo) objWorkpsace;
			} else {
				// workspace is unchanged
				workspace = ((StoreInfo) info).getWorkspace();
			}
			
			final StoreInfo localObject;
			if (info instanceof CoverageStoreInfo) {
				localObject = catalog.getStoreByName(workspace, name,
						CoverageStoreInfo.class);
			} else if (info instanceof DataStoreInfo) {
				localObject = catalog.getStoreByName(workspace, name,
						DataStoreInfo.class);
			} else if (info instanceof WMSStoreInfo) {
				localObject = catalog.getStoreByName(workspace, name,
						WMSStoreInfo.class);
			} else {
				throw new IllegalArgumentException(
						"Unable to provide localization for the passed instance");
			}

			if (localObject == null) {
				throw new CatalogException("Unable to locate " + info
						+ " named: " + name + " locally.");
			}

			BeanUtils.smartUpdate(localObject, modifyEv.getPropertyNames(),
					modifyEv.getNewValues());
			catalog.save(localObject);

		} else if (info instanceof ResourceInfo) {

			// check if name is changed
			if (name == null) {
				// name is unchanged
				name = ((ResourceInfo) info).getName();
			}
			// check if namespace is changed
			final NamespaceInfo namespace;
			final Object objWorkpsace = getOldValue(catalog, modifyEv,
					"namespace");
			if (objWorkpsace != null) {
				namespace = (NamespaceInfo) objWorkpsace;
			} else {
				// workspace is unchanged
				namespace = ((ResourceInfo) info).getNamespace();
			}
			final ResourceInfo localObject;
			if (info instanceof CoverageInfo) {
				// coverage
				localObject = catalog.getCoverageByName(namespace, name);
			} else if (info instanceof FeatureTypeInfo) {
				// feature
				localObject = catalog.getFeatureTypeByName(namespace, name);
			} else if (info instanceof WMSLayerInfo) {
				// wmslayer
				localObject = catalog.getResourceByName(namespace, name,
						WMSLayerInfo.class);
			} else {
				throw new IllegalArgumentException(
						"Unable to provide localization for the passed instance");
			}
			if (localObject == null) {
				throw new CatalogException("Unable to locate " + info
						+ " named: " + name + " locally.");
			}

			BeanUtils.smartUpdate(localObject, modifyEv.getPropertyNames(),
					modifyEv.getNewValues());
			catalog.save(localObject);

		} else if (info instanceof StyleInfo) {

			// check if name is changed
			if (name == null) {
				// name is unchanged
				name = ((StyleInfo) info).getName();
			}

			final StyleInfo localObject = catalog.getStyleByName(name);

			if (localObject == null) {
				throw new CatalogException("Unable to locate " + info
						+ " named: " + name + " locally.");
			}

			BeanUtils.smartUpdate(localObject, modifyEv.getPropertyNames(),
					modifyEv.getNewValues());
			catalog.save(localObject);

		} else if (info instanceof WorkspaceInfo) {

			// check if name is changed
			if (name == null) {
				// name is unchanged
				name = ((WorkspaceInfo) info).getName();
			}

			final WorkspaceInfo localObject = catalog.getWorkspaceByName(name);

			if (localObject == null) {
				throw new CatalogException("Unable to locate " + info
						+ " named: " + name + " locally.");
			}

			BeanUtils.smartUpdate(localObject, modifyEv.getPropertyNames(),
					modifyEv.getNewValues());
			catalog.save(localObject);

		} else if (info instanceof CatalogInfo) {

			// change default workspace in the handled catalog
			/**
			 * This piece of code was extracted from: {@link
			 * org.geoserver.catalog.NamespaceWorkspaceConsistencyListener.
			 * handleModifyEvent(CatalogModifyEvent)}
			 */
			final List<String> properties = modifyEv.getPropertyNames();
			if (properties.contains("defaultNamespace")) {
				final NamespaceInfo newDefault = (NamespaceInfo) modifyEv
						.getNewValues().get(
								properties.indexOf("defaultNamespace"));
				if (newDefault != null) {
					final WorkspaceInfo ws = catalog
							.getWorkspaceByName(newDefault.getPrefix());
					if (ws != null && !catalog.getDefaultWorkspace().equals(ws)) {
						catalog.setDefaultWorkspace(ws);
					}
				}
			} else if (properties.contains("defaultWorkspace")) {
				final WorkspaceInfo newDefault = (WorkspaceInfo) modifyEv
						.getNewValues().get(
								properties.indexOf("defaultWorkspace"));
				if (newDefault != null) {
					final NamespaceInfo ns = catalog
							.getNamespaceByPrefix(newDefault.getName());
					if (ns != null && !catalog.getDefaultNamespace().equals(ns)) {
						catalog.setDefaultNamespace(ns);
					}
				}
			}

		} else {
			if (LOGGER.isLoggable(java.util.logging.Level.WARNING)) {
				LOGGER.warning("info - ID: " + info.getId() + " toString: "
						+ info.toString());
			}
			throw new IllegalArgumentException("Bad incoming object: "
					+ info.toString());
		}
	}

	/**
	 * get the local old name for the passed CatalogInfo event
	 * 
	 * @param catalog
	 *            the catalog
	 * @param ev
	 *            the modify event
	 * @return a String representing the old name or null if name is not changed
	 *         or not exists at all
	 */
	private static String getOldName(final Catalog catalog,
			final CatalogModifyEvent ev) {
		// try to get the old value for the name
		final Object name = getOldValue(catalog, ev, "name");
		// check return and return a string representation of the name or null
		return name != null ? name.toString() : null;
	}

	/**
	 * get the old property for the passed CatalogInfo event
	 * 
	 * @param catalog
	 *            the catalog
	 * @param ev
	 *            the modify event
	 * @param oldProp
	 *            the name of the old property to search for
	 * @return an Object representing the old value of the passed property or
	 *         null if name is not changed or not exists at all
	 */
	private static Object getOldValue(final Catalog catalog,
			final CatalogModifyEvent ev, final String oldProp) {
		final CatalogInfo service = ev.getSource();
		if (service == null) {
			throw new IllegalArgumentException("passed service is null");
		}
		// check if name is changed
		final List<String> props = ev.getPropertyNames();
		final int index = props.indexOf(oldProp);
		if (index != -1) {
			final List<Object> oldValues = ev.getOldValues();
			// search the Service using the old name
			return oldValues.get(index);
		} else {
			return null;
		}

	}

}