/*
* Tigase Jabber/XMPP Server
* Copyright (C) 2004-2007 "Artur Hefczyc" <artur.hefczyc@tigase.org>
*
* 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 3 of the License.
*
* 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. Look for COPYING file in the top folder.
* If not, see http://www.gnu.org/licenses/.
*
* $Rev: 898 $
* Last modified by $Author: kobit $
* $Date: 2008-04-03 09:40:49 +0100 (Thu, 03 Apr 2008) $
*/
package tigase.server.ssender;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
//import java.sql.Date;
import java.util.HashSet;
import java.util.Set;
import java.util.Queue;
import java.util.LinkedList;
import java.util.logging.Level;
import java.util.logging.Logger;
import tigase.server.Packet;
import tigase.xmpp.StanzaType;
import tigase.xml.XMLUtils;
/**
* <code>DrupalForumTask</code> implements tasks for cyclic retrieving new
* posts on selected <a href="http://drupal.org/">Drupal</a> forum.
* It detects both new forum topics and new comments for forum topics.
* Then it can sends this to one selected JID. Thus it should be used toghether
* with StanzaReceiver task which can distribute this informatin to all interested
* (subscribed) users.
* <p>
* You have to specify forum ID for monitoring in connection string as well as
* destination JID where forum posts have to be sent. It is not very useful to
* send post to just one person so to ditribute forum posts to biger number of
* users this task should be paired with <code>StanzaReceiver</code> task which
* can distribute it to all interested users.
* Sample connection string:
* <pre>jdbc:mysql://localhost/tigasedb?user=tigase&password=pass&forum=3&jid=nick@domain.com</pre>
* </p>
* <p>
* Created: Fri Apr 20 12:10:55 2007
* </p>
* @author <a href="mailto:artur.hefczyc@tigase.org">Artur Hefczyc</a>
* @version $Rev: 898 $
*/
public class DrupalForumTask extends SenderTask {
/**
* Variable <code>log</code> is a class logger.
*/
private static final Logger log =
Logger.getLogger("tigase.server.ssender.DrupalForumTask");
private static final long SECOND = 1000;
/**
* <code>handler</code> is a reference to object processing stanza
* read from database.
*/
private StanzaHandler handler = null;
/**
* <code>db_conn</code> field stores database connection string.
*/
private String db_conn = null;
/**
* <code>conn</code> variable keeps connection to database.
*/
private Connection conn = null;
/**
* <code>get_new_topics</code> is a prepared statement for retrieving all
* new topics for drupal forum.
*/
private PreparedStatement get_new_topics = null;
/**
* <code>get_new_comments</code> is a prepared statement for retrieving all
* new comments from drupal forum.
*/
private PreparedStatement get_new_comments = null;
/**
* <code>conn_valid_st</code> is a prepared statement keeping query used
* to validate connection to database:
* <pre>select 1</pre>
*/
private PreparedStatement conn_valid_st = null;
/**
* <code>forumId</code> variable keeps drupal numerical forum ID which
* has to be monitored for new posts.
*/
private long forumId = -1;
/**
* <code>jid</code> keeps destination address where all new posts from
* the forum are sent.
*
*/
private String jid = null;
/**
* <code>lastCheck</code> keeps time of last forum topics check so it
* gets only new posts.
*
*/
protected long lastTopicsCheck = -1;
/**
* <code>lastCheck</code> keeps time of last forum comments check so it
* gets only new posts.
*
*/
protected long lastCommentsCheck = -1;
/**
* <code>lastConnectionValidated</code> variable keeps time where the
* connection was validated for the last time.
*/
private long lastConnectionValidated = 0;
/**
* <code>connectionValidateInterval</code> is kind of constant keeping minimum
* interval for validating connection to database.
*/
private long connectionValidateInterval = 1000*60;
/**
* <code>release</code> method releases some SQL query variables.
*
* @param rs a <code>ResultSet</code> value
*/
private void release(ResultSet rs) {
if (rs != null) {
try {
rs.close();
} catch (SQLException sqlEx) { }
}
}
/**
* <code>checkConnection</code> method checks whether connection to database
* is still valid, if not it simply reconnect and reinitializes database
* backend.
*
* @return a <code>boolean</code> value
* @exception SQLException if an error occurs
*/
private boolean checkConnection() throws SQLException {
try {
long tmp = System.currentTimeMillis();
if ((tmp - lastConnectionValidated) >= connectionValidateInterval) {
conn_valid_st.executeQuery();
lastConnectionValidated = tmp;
} // end of if ()
} catch (Exception e) {
initRepo();
} // end of try-catch
return true;
}
/**
* <code>findTableName</code> method parses database connection string to find
* table name where stanza packets are waiting for sending.
*
* @param db_str a <code>String</code> value
*/
private void findExtraParams(String db_str) {
String[] params = db_str.split("&");
for (String par: params) {
if (par.startsWith("jid=")) {
jid = par.substring("jid=".length(), par.length());
}
if (par.startsWith("forum")) {
try {
forumId =
Long.parseLong(par.substring("forum=".length(), par.length()));
} catch (NumberFormatException e) {
forumId = -1;
log.warning("Forum ID number is incorrect: "
+ par.substring("forum=".length(), par.length()));
}
}
}
}
/**
* <code>initRepo</code> method initializes database backend - connects to
* database, creates prepared statements and sets basic variables.
*
* @exception SQLException if an error occurs
*/
private void initRepo() throws SQLException {
conn = DriverManager.getConnection(db_conn);
conn.setAutoCommit(true);
String query = "select 1;";
conn_valid_st = conn.prepareStatement(query);
query = "select users.name as name, node_revisions.title as title,"
+ " node_revisions.body as body"
+ " from forum, node_revisions, users where"
+ " (status = 1) and (node_revisions.timestamp > ?)"
+ " and forum.tid = ? and users.uid = node_revisions.uid"
+ " and node_revisions.vid = forum.vid;";
get_new_topics = conn.prepareStatement(query);
query = "select name, thread, subject, comment "
+ "from comments where"
+ " (status = 0) and (timestamp > ?)"
+ " and (nid in (select nid from forum where tid = ?));";
get_new_comments = conn.prepareStatement(query);
}
/**
* <code>init</code> method is a task specific initialization rountine.
*
* @param handler a <code>StanzaHandler</code> value is a reference to object
* which handles all stanza retrieved from data source. The handler is
* responsible for delivering stanza to destination address.
* @param initString a <code>String</code> value is an initialization string
* for this task. For example database tasks would expect database connection
* string here, filesystem task would expect directory here.
* @exception IOException if an error occurs during task or data storage
* initialization.
*/
public void init(StanzaHandler handler, String initString) throws IOException {
this.handler = handler;
db_conn = initString;
findExtraParams(db_conn);
lastTopicsCheck = System.currentTimeMillis() / SECOND;
lastCommentsCheck = System.currentTimeMillis() / SECOND;
try {
initRepo();
} catch (SQLException e) {
throw new IOException("Problem initializing SenderTask.", e);
}
}
/**
* <code>getInitString</code> method returns initialization string passed
* to it in <code>init()</code> method.
*
* @return a <code>String</code> value of initialization string.
*/
public String getInitString() {
return db_conn;
}
public boolean cancel() {
boolean result = super.cancel();
try {
conn_valid_st.close();
get_new_topics.close();
get_new_comments.close();
conn.close();
} catch (Exception e) {
// Ignore.
}
return result;
}
private void newTopics(Queue<Packet> results) {
ResultSet rs = null;
try {
checkConnection();
get_new_topics.setLong(1, lastTopicsCheck);
lastTopicsCheck = System.currentTimeMillis() / SECOND;
get_new_topics.setLong(2, forumId);
rs = get_new_topics.executeQuery();
while (rs.next()) {
String name = rs.getString("name");
String title = rs.getString("title");
String body = rs.getString("body");
Packet msg = Packet.getMessage(jid, getName(), StanzaType.normal,
"New post by " + name + ":\n\n" + XMLUtils.escape(body),
XMLUtils.escape(title), null);
log.fine("Sending new topic: " + msg.toString());
results.offer(msg);
}
} catch (SQLException e) {
// Let's ignore it for now.
log.log(Level.WARNING, "Error retrieving stanzas from database: ", e);
// It should probably do kind of auto-stop???
// if so just uncomment below line:
//this.cancel();
} finally {
release(rs);
rs = null;
}
}
private void newComments(Queue<Packet> results) {
ResultSet rs = null;
try {
checkConnection();
// log.info("timestamp = " + lastCommentsCheck.toString());
get_new_comments.setLong(1, lastCommentsCheck);
lastCommentsCheck = System.currentTimeMillis() / SECOND;
get_new_comments.setLong(2, forumId);
rs = get_new_comments.executeQuery();
while (rs.next()) {
String name = rs.getString("name");
String thread = rs.getString("thread");
String subject = rs.getString("subject");
String comment = rs.getString("comment");
Packet msg = Packet.getMessage(jid, getName(), StanzaType.normal,
"New comment by " + name + ":\n\n" + XMLUtils.escape(comment),
XMLUtils.escape(subject), thread);
log.fine("Sending new comment: " + msg.toString());
results.offer(msg);
}
} catch (SQLException e) {
// Let's ignore it for now.
log.log(Level.WARNING, "Error retrieving stanzas from database: ", e);
// It should probably do kind of auto-stop???
// if so just uncomment below line:
//this.cancel();
} finally {
release(rs);
rs = null;
}
}
protected Queue<Packet> getNewPackets() {
Queue<Packet> results = new LinkedList<Packet>();
newTopics(results);
newComments(results);
return results;
}
/**
* <code>run</code> method is where all task work is done.
*/
public void run() {
// log.info("Task " + getName()
// + ", timestamp = " + lastCommentsCheck
// // + ", getTime() = " + lastCommentsCheck.getTime()
// + ", System.currentTimeMillis() = " + System.currentTimeMillis());
Queue<Packet> results = getNewPackets();
handler.handleStanzas(results);
}
}