/****************************************************************
* Licensed to the Apache Software Foundation (ASF) under one *
* or more contributor license agreements. See the NOTICE file *
* distributed with this work for additional information *
* regarding copyright ownership. The ASF licenses this file *
* to you under the Apache License, Version 2.0 (the *
* "License"); you may not use this file except in compliance *
* with the License. You may obtain a copy of the License at *
* *
* http://www.apache.org/licenses/LICENSE-2.0 *
* *
* Unless required by applicable law or agreed to in writing, *
* software distributed under the License is distributed on an *
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY *
* KIND, either express or implied. See the License for the *
* specific language governing permissions and limitations *
* under the License. *
****************************************************************/
package org.apache.james.transport.mailets;
import org.apache.avalon.cornerstone.services.datasources.DataSourceSelector;
import org.apache.avalon.excalibur.datasource.DataSourceComponent;
import org.apache.avalon.framework.service.ServiceManager;
import org.apache.james.Constants;
import org.apache.james.util.JDBCUtil;
import org.apache.mailet.GenericMailet;
import org.apache.mailet.Mail;
import org.apache.mailet.MailAddress;
import org.apache.mailet.MailetException;
import javax.mail.MessagingException;
import javax.mail.internet.ParseException;
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Collection;
import java.util.Iterator;
import java.util.Vector;
/**
* Rewrites recipient addresses based on a database table. The connection
* is configured by passing the URL to a conn definition. You need to set
* the table name to check (or view) along with the source and target columns
* to use. For example,
* <mailet match="All" class="JDBCAlias">
* <mappings>db://maildb/Aliases</mappings>
* <source_column>source_email_address</source_column>
* <target_column>target_email_address</target_column>
* </mailet>
*
*/
public class JDBCAlias extends GenericMailet {
protected DataSourceComponent datasource;
protected String query = null;
// The JDBCUtil helper class
private final JDBCUtil theJDBCUtil =
new JDBCUtil() {
protected void delegatedLog(String logString) {
log("JDBCAlias: " + logString);
}
};
/**
* Initialize the mailet
*/
public void init() throws MessagingException {
String mappingsURL = getInitParameter("mappings");
String datasourceName = mappingsURL.substring(5);
int pos = datasourceName.indexOf("/");
String tableName = datasourceName.substring(pos + 1);
datasourceName = datasourceName.substring(0, pos);
Connection conn = null;
if (getInitParameter("source_column") == null) {
throw new MailetException("source_column not specified for JDBCAlias");
}
if (getInitParameter("target_column") == null) {
throw new MailetException("target_column not specified for JDBCAlias");
}
try {
ServiceManager componentManager = (ServiceManager)getMailetContext().getAttribute(Constants.AVALON_COMPONENT_MANAGER);
// Get the DataSourceSelector service
DataSourceSelector datasources = (DataSourceSelector)componentManager.lookup(DataSourceSelector.ROLE);
// Get the data-source required.
datasource = (DataSourceComponent)datasources.select(datasourceName);
conn = datasource.getConnection();
// Check if the required table exists. If not, complain.
DatabaseMetaData dbMetaData = conn.getMetaData();
// Need to ask in the case that identifiers are stored, ask the DatabaseMetaInfo.
// Try UPPER, lower, and MixedCase, to see if the table is there.
if (!(theJDBCUtil.tableExists(dbMetaData, tableName))) {
StringBuffer exceptionBuffer =
new StringBuffer(128)
.append("Could not find table '")
.append(tableName)
.append("' in datasource '")
.append(datasourceName)
.append("'");
throw new MailetException(exceptionBuffer.toString());
}
//Build the query
StringBuffer queryBuffer =
new StringBuffer(128)
.append("SELECT ")
.append(getInitParameter("target_column"))
.append(" FROM ")
.append(tableName)
.append(" WHERE ")
.append(getInitParameter("source_column"))
.append(" = ?");
query = queryBuffer.toString();
} catch (MailetException me) {
throw me;
} catch (Exception e) {
throw new MessagingException("Error initializing JDBCAlias", e);
} finally {
theJDBCUtil.closeJDBCConnection(conn);
}
}
public void service(Mail mail) throws MessagingException {
//Then loop through each address in the recipient list and try to map it according to the alias table
Connection conn = null;
PreparedStatement mappingStmt = null;
ResultSet mappingRS = null;
Collection recipients = mail.getRecipients();
Collection recipientsToRemove = new Vector();
Collection recipientsToAdd = new Vector();
try {
conn = datasource.getConnection();
mappingStmt = conn.prepareStatement(query);
for (Iterator i = recipients.iterator(); i.hasNext(); ) {
try {
MailAddress source = (MailAddress)i.next();
mappingStmt.setString(1, source.toString());
mappingRS = mappingStmt.executeQuery();
if (!mappingRS.next()) {
//This address was not found
continue;
}
try {
String targetString = mappingRS.getString(1);
MailAddress target = new MailAddress(targetString);
//Mark this source address as an address to remove from the recipient list
recipientsToRemove.add(source);
recipientsToAdd.add(target);
} catch (ParseException pe) {
//Don't alias this address... there's an invalid address mapping here
StringBuffer exceptionBuffer =
new StringBuffer(128)
.append("There is an invalid alias from ")
.append(source)
.append(" to ")
.append(mappingRS.getString(1));
log(exceptionBuffer.toString());
continue;
}
} finally {
ResultSet localRS = mappingRS;
// Clear reference to result set
mappingRS = null;
theJDBCUtil.closeJDBCResultSet(localRS);
}
}
} catch (SQLException sqle) {
throw new MessagingException("Error accessing database", sqle);
} finally {
theJDBCUtil.closeJDBCStatement(mappingStmt);
theJDBCUtil.closeJDBCConnection(conn);
}
recipients.removeAll(recipientsToRemove);
recipients.addAll(recipientsToAdd);
}
/**
* Return a string describing this mailet.
*
* @return a string describing this mailet
*/
public String getMailetInfo() {
return "JDBC aliasing mailet";
}
}
|
