GenericLdapSearch.java

/*
 * This program is free software; you can redistribute it and/or modify it under the 
 * terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software 
 * Foundation.
 *
 * You should have received a copy of the GNU Lesser General Public License along with this 
 * program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html 
 * or from the Free Software Foundation, Inc., 
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * 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.
 *
 * Copyright 2007 - 2009 Pentaho Corporation.  All rights reserved.
 *
 */
package org.pentaho.platform.plugin.services.security.userrole.ldap.search;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import javax.naming.NamingEnumeration;
import javax.naming.NamingException;
import javax.naming.directory.SearchResult;

import org.apache.commons.collections.Transformer;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.ldap.core.ContextSource;
import org.springframework.util.Assert;

public class GenericLdapSearch implements LdapSearch, InitializingBean {

  // ~ Static fields/initializers ============================================
  private static final Log logger = LogFactory.getLog(GenericLdapSearch.class);

  // ~ Instance fields =======================================================

  /**
   * Generates disposable instances of search parameters. Factory should be
   * thread-safe (i.e. no mutable instance variables).
   * 
   * @see LdapSearchParams
   */
  private LdapSearchParamsFactory paramsFactory;

  /**
   * Transforms LDAP search results into custom objects. Can be chained
   * together. Transformer should be thread-safe (i.e. no mutable instance
   * variables).
   */
  private Transformer resultsTransformer;

  /**
   * Transforms filter arguments before passing to the
   * <code>paramsFactory</code>. On such example is transforming a
   * <code>GrantedAuthority</code> instance into a <code>String</code>
   * instance for searching. Transformer should be thread-safe (i.e. no
   * mutable instance variables).
   * <p>
   * <strong>Note that depending on the matching rules of the directory
   * server, case in strings may or may not matter.</strong>
   * </p>
   */
  private Transformer filterArgsTransformer;

	private ContextSource contextSource;

  // ~ Constructors ==========================================================

  public GenericLdapSearch(final ContextSource contextSource,
      final LdapSearchParamsFactory paramsFactory) {
    this(contextSource, paramsFactory, null, null);
  }

  public GenericLdapSearch(final ContextSource contextSource,
      final LdapSearchParamsFactory paramsFactory, final Transformer resultsTransformer) {
    this(contextSource, paramsFactory, resultsTransformer, null);
  }

  public GenericLdapSearch(final ContextSource contextSource,
      final LdapSearchParamsFactory paramsFactory, final Transformer resultsTransformer,
      final Transformer filterArgsTransformer) {
    super();
    this.contextSource = contextSource;
    this.paramsFactory = paramsFactory;
    this.resultsTransformer = resultsTransformer;
    this.filterArgsTransformer = filterArgsTransformer;
  }

  // ~ Methods ===============================================================

  public List search(final Object[] filterArgs) {
    Object[] transformedArgs = filterArgs;
    // transform the filterArgs
    if (null != filterArgsTransformer) {
      transformedArgs = (Object[]) filterArgsTransformer.transform(filterArgs);
    }
    LdapSearchParams params = paramsFactory.createParams(transformedArgs);
    // use a set internally to store intermediate results
    Set results = new HashSet();
    NamingEnumeration matches = null;
    try {
      matches = contextSource.getReadOnlyContext().search(params.getBase(), params.getFilter(),
          params.getFilterArgs(), params.getSearchControls());
    } catch (NamingException e1) {
      if (GenericLdapSearch.logger.isErrorEnabled()) {
        // TODO: Throw an exception here
        GenericLdapSearch.logger.error("Directory search failed", e1); //$NON-NLS-1$
      }
      return new ArrayList(results);
    }
    try {
      while (matches.hasMore()) {
        SearchResult result = (SearchResult) matches.next();
        if (null != resultsTransformer) {
          results.addAll((Collection) resultsTransformer.transform(result));
        } else {
          results.add(result);
        }
      }
    } catch (NamingException e) {
      if (GenericLdapSearch.logger.isErrorEnabled()) {
        // TODO: Throw an exception here
        GenericLdapSearch.logger.error("Enumerating directory search results failed", e); //$NON-NLS-1$
      }
    }
    return new ArrayList(results);
  }

  public void afterPropertiesSet() throws Exception {
    Assert.notNull(contextSource);
    Assert.notNull(paramsFactory);
  }
}