Metacat

/**

 *  '$RCSfile$'

 *    Purpose: A Class that implements properties methods for metacat

 *  Copyright: 2008 Regents of the University of California and the

 *             National Center for Ecological Analysis and Synthesis

 *    Authors: Michael Daigle

 *

 *   '$Author: daigle $'

 *     '$Date: 2009-08-24 14:34:17 -0700 (Mon, 24 Aug 2009) $'

 * '$Revision: 5030 $'

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU 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 General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */

package edu.ucsb.nceas.metacat.properties;

import java.util.Map;

import java.util.Vector;

import javax.servlet.ServletContext;

import javax.servlet.http.HttpServletRequest;

import org.apache.log4j.Logger;

import edu.ucsb.nceas.metacat.shared.BaseService;

import edu.ucsb.nceas.metacat.shared.ServiceException;

import edu.ucsb.nceas.utilities.FileUtil;

import edu.ucsb.nceas.utilities.GeneralPropertyException;

import edu.ucsb.nceas.utilities.PropertiesMetaData;

import edu.ucsb.nceas.utilities.PropertyNotFoundException;

import edu.ucsb.nceas.utilities.SortedProperties;

/**

 * A suite of utility classes for the metadata configuration utility

 */

public class PropertyService extends BaseService {

	private static PropertyService propertyService = null;

	private static PropertiesInterface properties = null;

	// system is configured

	public static final String CONFIGURED = PropertiesInterface.CONFIGURED;

	// system has never been configured

	public static final String UNCONFIGURED = PropertiesInterface.UNCONFIGURED;

	public static final String BYPASSED = PropertiesInterface.BYPASSED;

	private static String DEFAULT_CONFIG_FILE_DIR = "WEB-INF";

	public static String CONFIG_FILE_DIR = null;

	public static String CONFIG_FILE_NAME = null;

	public static String CONFIG_FILE_PATH = null;

	public static String TEST_CONFIG_FILE_NAME = null;

	private static String DEFAULT_PROPERTY_CLASS_NAME = "edu.ucsb.nceas.metacat.properties.ConfigurableProperties";

	private static String PROPERTY_CLASS_NAME = null;

	private static String RECOMMENDED_EXTERNAL_DIR = null;

	private static Logger logMetacat = Logger.getLogger(PropertyService.class);

	/**

	 * private constructor since this is a singleton

	 * 

	 * @param servletContext

	 *            the context we will use to get relative paths

	 */

	private PropertyService() throws ServiceException {

		_serviceName = "PropertyService";

		initialize();

	}

	/**

	 * Get the single instance of PropertyService.

	 * 

	 * @return the single instance of PropertyService

	 */

	public static PropertyService getInstance(ServletContext context)

			throws ServiceException {

		if (propertyService == null) {

			String applicationName = (String)context.getAttribute("APPLICATION_NAME");

			CONFIG_FILE_DIR = context.getInitParameter("configFileDir");

			if (CONFIG_FILE_DIR == null) {

				String configDir = context.getRealPath(DEFAULT_CONFIG_FILE_DIR);

				CONFIG_FILE_DIR = configDir;

			}

			CONFIG_FILE_PATH = CONFIG_FILE_DIR + FileUtil.getFS() + applicationName + ".properties";

			PROPERTY_CLASS_NAME = context.getInitParameter("propertyClassName");

			if (PROPERTY_CLASS_NAME == null) {

				PROPERTY_CLASS_NAME = DEFAULT_PROPERTY_CLASS_NAME;

			}

			propertyService = new PropertyService();

		}

		return propertyService;

	}

	 /**

	 * Get the single instance of PropertyService for test purposes. In this

	 * case, we allow the configuration directory to be passed in.

	 *

	 * @param configDir the configuration directory we need to look in

	 * @return the single instance of PropertyService

	 */

	 public static PropertyService getInstance(String testConfigFileDir)

			throws ServiceException {

		if (propertyService == null) {

			CONFIG_FILE_DIR = testConfigFileDir;

			PROPERTY_CLASS_NAME = DEFAULT_PROPERTY_CLASS_NAME;

			propertyService = new PropertyService();

		}

		return propertyService;

	}

	 /**

		 * Get the single instance of PropertyService for test purposes. In this

		 * case, we allow the configuration directory to be passed in.

		 *

		 * @param configDir the configuration directory we need to look in

		 * @return the single instance of PropertyService

		 */

		 public static PropertyService getInstance() throws ServiceException {

			if (propertyService == null) {

				throw new ServiceException("PropertyService.getInstance - cannot call " +

						"getInstance without parameters until property service has been created " +

						"with either servlet context or config file path.");

			}

			return propertyService;

		}

	public boolean refreshable() {

		return true;

	}

	public void doRefresh() throws ServiceException {

		// initialize();

	}

	public void stop() throws ServiceException {

		return;

	}

	/**

	 * Initialize the singleton.

	 * 

	 * @param servletContext

	 *            the context we will use to get relative paths

	 */

	private void initialize() throws ServiceException {

		logMetacat.debug("Initializing PropertyService");

		try {

			Class<?> classDef = Class.forName(PROPERTY_CLASS_NAME);

			properties = (PropertiesInterface) classDef.newInstance();

		} catch (InstantiationException ie) {

			throw new ServiceException("Could not instantiate property class: "

					+ PROPERTY_CLASS_NAME + " " + ie.getMessage());

		} catch (IllegalAccessException iae) {

			throw new ServiceException("Access error when intantiating property class: "

					+ PROPERTY_CLASS_NAME + " " + iae.getMessage());

		} catch (ClassNotFoundException cnfe) {

			throw new ServiceException("Could not find property class: "

					+ PROPERTY_CLASS_NAME + " " + cnfe.getMessage());

		}

	}

	/**

	 * Utility method to get a property value from the properties file

	 * 

	 * @param propertyName

	 *            the name of the property requested

	 * @return the String value for the property

	 */

	public static String getProperty(String propertyName)

			throws PropertyNotFoundException {

		return properties.getProperty(propertyName);

	}

	/**

	 * Get a set of all property names.

	 * 

	 * @return Set of property names

	 */

	public static Vector<String> getPropertyNames() {

		return properties.getPropertyNames();

	}

	/**

	 * Get a Set of all property names that start with the groupName prefix.

	 * 

	 * @param groupName

	 *            the prefix of the keys to search for.

	 * @return enumeration of property names

	 */

	public static Vector<String> getPropertyNamesByGroup(String groupName) {

		return properties.getPropertyNamesByGroup(groupName);

	}

	/**

	 * Get a Map of all properties that start with the groupName prefix.

	 * 

	 * @param groupName

	 *            the prefix of the keys to search for.

	 * @return Map of property names

	 */

	public static Map<String, String> getPropertiesByGroup(String groupName)

			throws PropertyNotFoundException {

		return properties.getPropertiesByGroup(groupName);

	}

	/**

	 * Utility method to set a property value both in memory and to the

	 * properties file

	 * 

	 * @param propertyName

	 *            the name of the property requested

	 * @param newValue

	 *            the new value for the property

	 */

	public static void setProperty(String propertyName, String newValue)

			throws GeneralPropertyException {

		properties.setProperty(propertyName, newValue);

		properties.persistProperties();

	}

	/**

	 * Utility method to set a property value in memory. This will NOT cause the

	 * property to be written to disk. Use this method to set multiple

	 * properties in a row without causing excessive I/O. You must call

	 * persistProperties() once you're done setting properties to have them

	 * written to disk.

	 * 

	 * @param propertyName

	 *            the name of the property requested

	 * @param newValue

	 *            the new value for the property

	 */

	public static void setPropertyNoPersist(String propertyName, String newValue)

			throws GeneralPropertyException {

		properties.setPropertyNoPersist(propertyName, newValue);

	}

	/**

	 * Save the properties to a properties file. Note, the order and comments

	 * will be preserved.

	 */

	public static void persistProperties() throws GeneralPropertyException {

		properties.persistProperties();

	}

	/**

	 * Get the main backup properties file. These are configurable properties

	 * that are stored outside the metacat install directories so the user does

	 * not need to re-enter all the configuration information every time they do

	 * an upgrade.

	 * 

	 * @return a SortedProperties object with the backup properties

	 */

	public static SortedProperties getMainBackupProperties() throws GeneralPropertyException {

		return properties.getMainBackupProperties();

	}

	/**

	 * Get the auth backup properties file. These are configurable properties

	 * that are stored outside the metacat install directories so the user does

	 * not need to re-enter all the configuration information every time they do

	 * an upgrade.

	 * 

	 * @return a SortedProperties object with the backup properties

	 */

	public static SortedProperties getAuthBackupProperties() throws GeneralPropertyException{

		return properties.getAuthBackupProperties();

	}

	/**

	 * Get the main properties metadata. This is retrieved from an xml file that

	 * describes the attributes of configurable properties.

	 * 

	 * @return a PropertiesMetaData object with the main properties metadata

	 */

	public static PropertiesMetaData getMainMetaData() throws GeneralPropertyException{

		return properties.getMainMetaData();

	}

	/**

	 * Get the auth properties metadata. This is retrieved from an xml file that

	 * describes the attributes of configurable properties.

	 * 

	 * @return a PropertiesMetaData object with the organization properties

	 *         metadata

	 */

	public static PropertiesMetaData getAuthMetaData() throws GeneralPropertyException{

		return properties.getAuthMetaData();

	}

	/**

	 * Writes out backup configurable properties to a file.

	 */

	public static void persistMainBackupProperties() throws GeneralPropertyException {

		properties.persistMainBackupProperties();

	}

	/**

	 * Writes out backup configurable properties to a file.

	 */

	public static void persistAuthBackupProperties(ServletContext servletContext)

			throws GeneralPropertyException {

		properties.persistAuthBackupProperties(servletContext);

	}

	/**

	 * Reports whether properties are fully configured.

	 * 

	 * @return a boolean that is true if properties are not unconfigured and

	 *         false otherwise

	 */

	public static boolean arePropertiesConfigured() throws GeneralPropertyException {

		return properties.arePropertiesConfigured();

	}

	/**

	 * Determine if the system is configured to bypass configuration. If so, the

	 * system will look for backup configuration files at startup time and use

	 * those to configure metacat. The bypass options should only be set by

	 * developers. Production code should never bypass confguration.

	 * 

	 * @return true if dev.runConfiguration is set to true in metacat.properties

	 *         and we have not already checked for bypass, false otherwise.

	 */

	public static boolean doBypass() throws GeneralPropertyException {

		return properties.doBypass();

	}

	/**

	 * Reports whether the metacat configuration utility should be run. Returns

	 * false if -- dev.runConfiguration=false and -- backup properties file

	 * exists Note that dev.runConfiguration should only be set to false when

	 * reinstalling the same version of the application in developement.

	 * 

	 * @return a boolean that is false if dev.runConfiguration is false and the

	 *         backup properties file exists.

	 */

	public static void bypassConfiguration() throws GeneralPropertyException {

		properties.bypassConfiguration();

	}

	/**

	 * Take input from the user in an HTTP request about an property to be

	 * changed and update the metacat property file with that new value if it

	 * has changed from the value that was originally set.

	 * 

	 * @param request

	 *            that was generated by the user

	 * @param response

	 *            to send output back to the user

	 * @param propertyName

	 *            the name of the property to be checked and set

	 */

	public static void checkAndSetProperty(HttpServletRequest request, String propertyName)

			throws GeneralPropertyException {

		properties.checkAndSetProperty(request, propertyName);

	}

	/**

	 * Sets the recommended external directory. This is populated during

	 * initialization time using the SystemUtil.discoverExternalDir() method.

	 * This directory will be used to suggest external user directories when the

	 * user configures metacat for the first time.

	 * 

	 */

	public static void setRecommendedExternalDir(String extBaseDir) {

		RECOMMENDED_EXTERNAL_DIR = extBaseDir;

	}

	/**

	 * Returns the recommended external base directory. This is populated during

	 * initialization time using the SystemUtil.discoverExternalBaseDir()

	 * method. This directory will be used to suggest external user directories

	 * when the user configures metacat for the first time.

	 * 

	 * @return a String holding the recommended external directory

	 */

	public static String getRecommendedExternalDir() {

		return RECOMMENDED_EXTERNAL_DIR;

	}

}