Metacat

/**

 *  '$RCSfile$'

 *  Copyright: 2000 Regents of the University of California and the

 *             National Center for Ecological Analysis and Synthesis

 *    Authors: Jivka Bojilova

 *    Release: @release@

 *

 *   '$Author$'

 *     '$Date$'

 * '$Revision$'

 *

 * 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;

import java.io.*;

import java.sql.*;

import java.util.Stack;

import java.util.Vector;

import java.util.Hashtable;

import java.net.URL;

import java.net.MalformedURLException;

import org.xml.sax.Attributes;

import org.xml.sax.InputSource;

import org.xml.sax.ContentHandler;

import org.xml.sax.EntityResolver;

import org.xml.sax.ErrorHandler;

import org.xml.sax.SAXException;

import org.xml.sax.SAXParseException;

import org.xml.sax.XMLReader;

import org.xml.sax.helpers.XMLReaderFactory;

import org.xml.sax.helpers.DefaultHandler;

/** 

 * A Class that read an eml-access.xml file containing ACL for a metadata

 * document and parse it into access rules

 */

public class AccessRulesFromDocument extends DefaultHandler {

  private static final int CHMOD = 1;

  private static final int WRITE = 2;

  private static final int READ = 4;

  private static final int ALL = 7;

  private static final String ALLOWFIRST="allowFirst";

  private static final String DENYFIRST="denyFirst";

  private static final String ALLOW="allow";

  private static final String DENY="deny";

  private static final String PUBLIC="public";

  private static String sysdate = MetaCatUtil.dbAdapter.getDateTimeFunction();

  private static String isnull = MetaCatUtil.dbAdapter.getIsNULLFunction();

  private String parserName;

  private Stack elementStack;

  private String server;

  private String sep;

  private boolean	processingDTD;

  private String  aclid;

  private int     rev;

  private String 	docname;

  private String 	doctype;

  private String 	systemid;

  private String docurl;

  private Vector resourceURL;

  private Vector resourceID;

  private Vector principal;

  private int    permission;

  private String permType;

  private String permOrder;

//  private String publicAcc;

  private String beginTime;

  private String endTime;

  private int    ticketCount;

  private int    serverCode = 1;

  private Vector aclObjects = new Vector();

  private boolean instarttag = true;

  private String tagName = "";

  private Vector accessRuleVector = new Vector();

  /**

   * Construct an instance of the AccessControlList class.

   * It parse acl file and loads acl data into db connection.

   *

   * @param aclid the Accession# of the document with the acl data

   * @param serverCode the serverid from xml_replication on which this document

   *        resides.

   */

  public AccessRulesFromDocument(String aclid)

                  throws SAXException, IOException, McdbException, SQLException

  {

    String parserName = MetaCatUtil.getOption("saxparser");

    this.server = MetaCatUtil.getOption("server");

    this.sep = MetaCatUtil.getOption("accNumSeparator");

    this.parserName = parserName;

    this.processingDTD = false;

    this.elementStack = new Stack();

    this.aclid = aclid;

    this.resourceURL = new Vector();

    this.resourceID = new Vector();

    this.principal = new Vector();

    this.permission = 0;

    this.ticketCount = 0;

    // read the access file from db connection

    DocumentImpl acldoc = new DocumentImpl(aclid);

    String acl = acldoc.toString();

    this.rev = acldoc.getRev();

    // Initialize the parse

    XMLReader parser = initializeParser();

    // parse the access file and write the info to xml_access

    parser.parse(new InputSource(new StringReader(acl)));

  }

  /* Set up the SAX parser for reading the XML serialized ACL */

  private XMLReader initializeParser() throws SAXException, SQLException

  {

    XMLReader parser = null;

    // Get an instance of the parser

    parser = XMLReaderFactory.createXMLReader(parserName);

    // Turn off validation

    parser.setFeature("http://xml.org/sax/features/validation", true);

    // Set Handlers in the parser

    // Set the ContentHandler to this instance

    parser.setContentHandler((ContentHandler)this);

    // make a DBEntityResolver instance

    // Set the EntityReslover to DBEntityResolver instance

    DBConnection conn = null;

    int serialNumber = -1;

    try

    {

      //get connection from DBConnectionPool

      conn=DBConnectionPool.getDBConnection("AccessControlList.getACLObject");

      serialNumber=conn.getCheckOutSerialNumber();

      EntityResolver eresolver = new DBEntityResolver(conn, this, null);

      parser.setEntityResolver((EntityResolver)eresolver);

    }

    finally

    {

      //retrun DBConnection

      DBConnectionPool.returnDBConnection(conn,serialNumber);

    }

    // Set the ErrorHandler to this instance

    parser.setErrorHandler((ErrorHandler)this);

    return parser; 

  }

  /**

   * Callback method used by the SAX Parser when beginning of the document

   */

  public void startDocument() throws SAXException 

  {

    //delete all previously submitted permissions @ relations

    //this happens only on UPDATE of the access file

    try {

      this.aclObjects = createACLObjects(aclid);

      //delete all permissions for resources related to @aclid if any

      /*if ( aclid != null ) {

        deletePermissionsForRelatedResources(aclid);

      }*/

    } catch (SQLException sqle) {

      throw new SAXException(sqle);

    }

  }

  /**

   * Callback method used by the SAX Parser when the start tag of an 

   * element is detected. Used in this context to parse and store

   * the acl information in class variables.

   */

  public void startElement (String uri, String localName, 

                            String qName, Attributes atts) 

         throws SAXException 

  {

    instarttag = true;

    if(localName.equals("allow"))

    {

      tagName = "allow";

    }

    else if(localName.equals("deny"))

    {

      tagName = "deny";

    }

    BasicNode currentNode = new BasicNode(localName);

    if (atts != null) {

      int len = atts.getLength();

      for (int i = 0; i < len; i++) {

        currentNode.setAttribute(atts.getLocalName(i), atts.getValue(i));

      }

    }

    if ( currentNode.getTagName().equals("acl") ) {

      permOrder = currentNode.getAttribute("order");

    }

    elementStack.push(currentNode); 

  }

  /**

   * Callback method used by the SAX Parser when the text sequences of an 

   * xml stream are detected. Used in this context to parse and store

   * the acl information in class variables.

   */ 

  public void characters(char ch[], int start, int length)

         throws SAXException 

  {

    if(!instarttag)

    {

      return;

    }

    String inputString = new String(ch, start, length);

    inputString = inputString.trim(); 

    //System.out.println("==============inputString: " + inputString);

    BasicNode currentNode = (BasicNode)elementStack.peek(); 

    String currentTag = currentNode.getTagName();

      if (currentTag.equals("principal")) {

        principal.addElement(inputString);

      } else if (currentTag.equals("permission")) {

        if ( inputString.trim().toUpperCase().equals("READ") ) {

          permission = permission | READ;

        } else if ( inputString.trim().toUpperCase().equals("WRITE") ) {

          permission = permission | WRITE;

        } else if ( inputString.trim().toUpperCase().equals("CHANGEPERMISSION")) 

        {

          permission = permission | CHMOD;

        } else if ( inputString.trim().toUpperCase().equals("ALL") ) {

          permission = permission | ALL;

        }/*else{

          throw new SAXException("Unknown permission type: " + inputString);

        }*/

      } else if ( currentTag.equals("startDate") && beginTime == null ) {

        beginTime = inputString.trim();

      } else if ( currentTag.equals("stopDate") && endTime == null) {

        endTime = inputString.trim();

      } else if (currentTag.equals("ticketCount") && ticketCount == 0 ) {

        try {

          ticketCount = (new Integer(inputString.trim())).intValue();

        } catch (NumberFormatException nfe) {

          throw new SAXException("Wrong integer format for:" + inputString);

        }

      }

  }

  /**

   * Callback method used by the SAX Parser when the end tag of an 

   * element is detected. Used in this context to parse and store

   * the acl information in class variables.

   */

  public void endElement (String uri, String localName, String qName)

         throws SAXException 

  {

    String oneAccessRule = null; 

    instarttag = false;

    BasicNode leaving = (BasicNode)elementStack.pop();

    String leavingTagName = leaving.getTagName();

    if ( leavingTagName.equals("allow") ||

         leavingTagName.equals("deny")    ) {

      if ( permission > 0 ) {

        // create a rule string an put it into rule vector.

        try 

        {

           for (int j = 0; j < principal.size(); j++ )

           {

             oneAccessRule = (String)principal.elementAt(j)+" ";

             oneAccessRule = oneAccessRule + leavingTagName + " ";

             oneAccessRule = oneAccessRule + permission + " ";

             oneAccessRule = oneAccessRule + permOrder;

             // inserinto accessRuleVector

             accessRuleVector.addElement(oneAccessRule);

           }

        } 

        catch (Exception e) 

        {

          throw new SAXException(e);

        }

      }

      // reset the allow/deny permission

      principal = new Vector();

      permission = 0;

      beginTime = null;

      endTime = null;

      ticketCount = 0;

    }

  }

  /** 

    * SAX Handler that receives notification of DOCTYPE. Sets the DTD.

    * @param name name of the DTD

    * @param publicId Public Identifier of the DTD

    * @param systemId System Identifier of the DTD

    */

  public void startDTD(String name, String publicId, String systemId) 

              throws SAXException {

    docname = name;

    doctype = publicId;

    systemid = systemId;

  }

  /** 

   * SAX Handler that receives notification of the start of entities.

   * @param name name of the entity

   */

  public void startEntity(String name) throws SAXException {

    if (name.equals("[dtd]")) {

      processingDTD = true;

    }

  }

  /** 

   * SAX Handler that receives notification of the end of entities.

   * @param name name of the entity

   */

  public void endEntity(String name) throws SAXException {

    if (name.equals("[dtd]")) {

      processingDTD = false;

    }

  }

  /**

   * Get the document name.

   */

  public String getDocname() {

    return docname;

  }

  /**

   * Get the document processing state.

   */

  public boolean processingDTD() {

    return processingDTD;

  }

  /**

   * Method to get accessRuleVector

   */

  public Vector getAccessRuleVector()

  {

    return accessRuleVector;

  }

  /**

   * Method to get ACLObjects

   */

  public Vector getACLObjects()

  {

    return aclObjects;

  }

  /* Get all objects associated with @aclid from db.*/

  private Vector createACLObjects(String aclid) 

          throws SQLException 

  {

    Vector aclObjects = new Vector();

    DBConnection conn = null;

    int serialNumber = -1;

    PreparedStatement pstmt = null;

    try

    {

      //get connection from DBConnectionPool

      conn=DBConnectionPool.getDBConnection("AccessControlList.getACLObject");

      serialNumber=conn.getCheckOutSerialNumber();

      // delete all acl records for resources related to @aclid if any

      pstmt = conn.prepareStatement(

                             "SELECT object FROM xml_relation " +

                             "WHERE subject = ? ");

      pstmt.setString(1,aclid);

      pstmt.execute();

      ResultSet rs = pstmt.getResultSet();

      boolean hasRows = rs.next();

      while (hasRows) {

        aclObjects.addElement(rs.getString(1));

        hasRows = rs.next();

      }//while

      // Add access file itself

      aclObjects.addElement(aclid);

    }

    catch (SQLException e)

    {

      throw e;

    }

    finally

    {

      try

      {

        pstmt.close();

      }

      finally

      {

        //retrun DBConnection

        DBConnectionPool.returnDBConnection(conn,serialNumber);

      }

    }

    return aclObjects;

  }

  /* Get the int value of READ, WRITE or ALL. */

  private static int intValue ( String permission )

  {

    if ( permission.equals("READ") ) {

      return READ;

    } else if ( permission.equals("WRITE") ) {

      return WRITE;

    } else if ( permission.equals("ALL") ) {

      return ALL;

    }

    return -1;

  }

  /* Get the text value of READ, WRITE or ALL. */

  private String txtValue ( int permission )

  {

    StringBuffer txtPerm = new StringBuffer("\"");

    if ( (permission & READ) != 0 ) {

      txtPerm.append("read");

    } 

    if ( (permission & WRITE) != 0 ) {

      if ( txtPerm.length() > 0 ) txtPerm.append(",");

      txtPerm.append("write");

    }

    if ( (permission & ALL) != 0 ) {

      if ( txtPerm.length() > 0 ) txtPerm.append(",");

      txtPerm.append("all");

    }

    return txtPerm.append("\"").toString();

  }

  public static void main(String[] agus)

  {

    if(agus.length == 0)

    {

      System.out.println("you should specify a docid!");

      return;

    }

    String docID = agus[0];

    try

    {

      DBConnectionPool pool = DBConnectionPool.getInstance();

      AccessRulesFromDocument xmlDocument = new AccessRulesFromDocument(docID);

      Vector rules = xmlDocument.getAccessRuleVector();

      Vector docid = xmlDocument.getACLObjects();

      for (int i = 0; i<rules.size(); i++)

      {

        System.out.println("rule: "+(String)rules.elementAt(i));

      }

      for (int i = 0; i<docid.size(); i++)

      {

        System.out.println("docid: "+(String)docid.elementAt(i));

      }

    }

    catch(Exception e)

    {

      System.out.println("exception is: "+e.getMessage());

    }

  }

}