源码详解openfire保存消息记录

实现openfire消息记录通常有两种方式，修改服务端和添加消息记录插件。

今天，简单的说明一下修改服务端方式实现消息记录保存功能。

实现思路

修改前：

默认的，openfire只提供保存离线记录至ofOffline表中。当发送一条消息时，判断用户是否在线，若为true，不保存消息；若为fasle，保存消息至离线消息表中。

修改后：

仿照保存离线消息，用户每发送一条消息，将消息存放在ofHistory表中，ofHistory表结构同ofOffline

实现步骤：

1.修改初始数据库文件，路径src/database/openfire_sqlserver.sql

添加ofHistory表

[sql] view plaincopyprint?

CREATE TABLE ofHistory (

username NVARCHAR(64) NOT NULL,

messageID INTEGER NOT NULL,

creationDate NVARCHAR(64) NOT NULL,

messageSize INTEGER NOT NULL,

stanza TEXT NOT NULL,

CONSTRAINT ofHistory_pk PRIMARY KEY (username, messageID)

);

CREATE TABLE ofOffline (

username NVARCHAR(64) NOT NULL,

messageID INTEGER NOT NULL,

creationDate CHAR(15) NOT NULL,

messageSize INTEGER NOT NULL,

stanza NTEXT NOT NULL,

CONSTRAINT ofOffline_pk PRIMARY KEY (username, messageID)

);

注：其他数据库修改方式雷同

2.添加保存消息方法

MessageRouter类中110行

[java] view plaincopyprint?

try {

// Deliver stanza to requested route

routingTable.routePacket(recipientJID, packet, false);

//保存消息记录dml@2013.4.15

OfflineMessageStore oms = new OfflineMessageStore();

oms.addMessage_toHistory(packet);

         }

         catch (Exception e) {

            log.error("Failed to route packet: " + packet.toXML(), e);

             routingFailed(recipientJID, packet);

         }

3.修改OfflineMessageStore类，添加保存消息记录方法

[java] view plaincopyprint?

/**

$RCSfile$
$Revision: 2911 $
$Date: 2005-10-03 12:35:52 -0300 (Mon, 03 Oct 2005) $
Copyright (C) 2004-2008 Jive Software. All rights reserved.
Licensed 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.jivesoftware.openfire;

import java.io.StringReader;

import java.sql.Connection;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.text.SimpleDateFormat;

import java.util.ArrayList;

import java.util.Collection;

import java.util.Date;

import java.util.List;

import java.util.Map;

import java.util.concurrent.BlockingQueue;

import java.util.concurrent.LinkedBlockingQueue;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

import org.dom4j.DocumentException;

import org.dom4j.Element;

import org.dom4j.io.SAXReader;

import org.jivesoftware.database.DbConnectionManager;

import org.jivesoftware.database.SequenceManager;

import org.jivesoftware.openfire.container.BasicModule;

import org.jivesoftware.openfire.event.UserEventDispatcher;

import org.jivesoftware.openfire.event.UserEventListener;

import org.jivesoftware.openfire.user.User;

import org.jivesoftware.openfire.user.UserManager;

import org.jivesoftware.util.JiveConstants;

import org.jivesoftware.util.LocaleUtils;

import org.jivesoftware.util.StringUtils;

import org.jivesoftware.util.XMPPDateTimeFormat;

import org.jivesoftware.util.cache.Cache;

import org.jivesoftware.util.cache.CacheFactory;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.xmpp.packet.JID;

import org.xmpp.packet.Message;

/**

Represents the user's offline message storage. A message store holds messages
that were sent to the user while they were unavailable. The user can retrieve
their messages by setting their presence to "available". The messages will
then be delivered normally. Offline message storage is optional, in which
case a null implementation is returned that always throws
UnauthorizedException when adding messages to the store.
@author Iain Shigeoka

*/

public class OfflineMessageStore extends BasicModule implements

UserEventListener {

private static final Logger Log = LoggerFactory

.getLogger(OfflineMessageStore.class);

// 保存消息记录 dml@2013.4.16

private static final String INSERT_HISTORY = "INSERT INTO ofHistory (username, messageID, creationDate, messageSize, stanza) "

+ "VALUES (?, ?, ?, ?, ?)";

private static final String INSERT_OFFLINE = "INSERT INTO ofOffline (username, messageID, creationDate, messageSize, stanza) "

+ "VALUES (?, ?, ?, ?, ?)";

private static final String LOAD_OFFLINE = "SELECT stanza, creationDate FROM ofOffline WHERE username=?";

private static final String LOAD_OFFLINE_MESSAGE = "SELECT stanza FROM ofOffline WHERE username=? AND creationDate=?";

private static final String SELECT_SIZE_OFFLINE = "SELECT SUM(messageSize) FROM ofOffline WHERE username=?";

private static final String SELECT_SIZE_ALL_OFFLINE = "SELECT SUM(messageSize) FROM ofOffline";

private static final String DELETE_OFFLINE = "DELETE FROM ofOffline WHERE username=?";

private static final String DELETE_OFFLINE_MESSAGE = "DELETE FROM ofOffline WHERE username=? AND creationDate=?";

private static final int POOL_SIZE = 10;

private Cache<String, Integer> sizeCache;

/**
- Pattern to use for detecting invalid XML characters. Invalid XML
- characters will be removed from the stored offline messages.
  
  */
  
  private Pattern pattern = Pattern.compile("&\#[\d]+;");
/**
- Returns the instance of OfflineMessageStore being used by the
- XMPPServer.
- @return the instance of OfflineMessageStore being used by the
- ```
    XMPPServer.
```
*/

public static OfflineMessageStore getInstance() {

return XMPPServer.getInstance().getOfflineMessageStore();

}

/**
- Pool of SAX Readers. SAXReader is not thread safe so we need to have a
- pool of readers.
  
  */
  
  private BlockingQueue xmlReaders = new LinkedBlockingQueue(
  
  POOL_SIZE);
/**
- Constructs a new offline message store.
  
  */
  
  public OfflineMessageStore() {
  
  super("Offline Message Store");
  
  sizeCache = CacheFactory.createCache("Offline Message Size");
  
  }
/**
- Adds a message to this message store. Messages will be stored and made
- available for later delivery.
- @param message
- ```
       the message to store.
```
*/

public void addMessage(Message message) {

if (message == null) {

return;

}

// ignore empty bodied message (typically chat-state notifications).

if (message.getBody() == null || message.getBody().length() == 0) {

// allow empty pubsub messages (OF-191)

if (message.getChildElement("event",

"http://jabber.org/protocol/pubsub#event") == null) {

return;

}

}

JID recipient = message.getTo();

String username = recipient.getNode();

// If the username is null (such as when an anonymous user), don't

// store.

if (username == null

|| !UserManager.getInstance().isRegisteredUser(recipient)) {

return;

} else if (!XMPPServer.getInstance().getServerInfo().getXMPPDomain()

.equals(recipient.getDomain())) {

// Do not store messages sent to users of remote servers

return;

}
```
 long messageID = SequenceManager.nextID(JiveConstants.OFFLINE);  

 // Get the message in XML format.

 String msgXML = message.getElement().asXML();  

 Connection con = null;

 PreparedStatement pstmt = null;

 try {

     con = DbConnectionManager.getConnection();

     pstmt = con.prepareStatement(INSERT_OFFLINE);

     pstmt.setString(1, username);

     pstmt.setLong(2, messageID);

     pstmt.setString(3, StringUtils.dateToMillis(new java.util.Date()));

     // SimpleDateFormat df = new

     // SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

     // pstmt.setString(3, df.format(new Date()).toString());   

     pstmt.setInt(4, msgXML.length());

     pstmt.setString(5, msgXML);

     pstmt.executeUpdate();

 }  

 catch (Exception e) {

     Log.error(LocaleUtils.getLocalizedString("admin.error"), e);

 } finally {

     DbConnectionManager.closeConnection(pstmt, con);

 }  

 // Update the cached size if it exists.

 if (sizeCache.containsKey(username)) {

     int size = sizeCache.get(username);

     size += msgXML.length();

     sizeCache.put(username, size);

 }
```
}

/**
- 保存消息记录
- @author dml
- @param message
  
  */
  
  public void addMessage_toHistory(Message message) {
  
  if (message == null) {
  
  return;
  
  }
  
  // ignore empty bodied message (typically chat-state notifications).
  
  if (message.getBody() == null || message.getBody().length() == 0) {
  
  // allow empty pubsub messages (OF-191)
  
  if (message.getChildElement("event",
  
  "http://jabber.org/protocol/pubsub#event") == null) {
  
  return;
  
  }
  
  }
  
  JID recipient = message.getTo();
  
  String username = recipient.getNode();
  
  // If the username is null (such as when an anonymous user), don't
  
  // store.
  
  if (username == null
  
  || !UserManager.getInstance().isRegisteredUser(recipient)) {
  
  return;
  
  } else if (!XMPPServer.getInstance().getServerInfo().getXMPPDomain()
  
  .equals(recipient.getDomain())) {
  
  // Do not store messages sent to users of remote servers
  
  return;
  
  }
  
  long messageID = SequenceManager.nextID(JiveConstants.OFFLINE);
  
  // Get the message in XML format.
  
  String msgXML = message.getElement().asXML();
  
  Connection con = null;
  
  PreparedStatement pstmt = null;
  
  try {
  
  con = DbConnectionManager.getConnection();
  
  pstmt = con.prepareStatement(INSERT_HISTORY);
  
  pstmt.setString(1, username);
  
  pstmt.setLong(2, messageID);
  
  // pstmt.setString(3, StringUtils.dateToMillis(new
  
  // java.util.Date()));
  
  SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
  
  pstmt.setString(3, df.format(new Date()).toString());
```
 pstmt.setInt(4, msgXML.length());

 pstmt.setString(5, msgXML);

 pstmt.executeUpdate();
```
  }
  
  catch (Exception e) {
  
  Log.error(LocaleUtils.getLocalizedString("admin.error"), e);
  
  } finally {
  
  DbConnectionManager.closeConnection(pstmt, con);
  
  }
  
  // Update the cached size if it exists.
  
  if (sizeCache.containsKey(username)) {
  
  int size = sizeCache.get(username);
  
  size += msgXML.length();
  
  sizeCache.put(username, size);
  
  }
  
  }
/**
- Returns a Collection of all messages in the store for a user. Messages
- may be deleted after being selected from the database depending on the
- delete param.
- @param username
- ```
       the username of the user who's messages you'd like to receive.
```
- @param delete
- ```
       true if the offline messages should be deleted.
```
- @return An iterator of packets containing all offline messages.
  
  */
  
  public Collection getMessages(String username,
  
  boolean delete) {
  
  List messages = new ArrayList();
  
  SAXReader xmlReader = null;
  
  Connection con = null;
  
  PreparedStatement pstmt = null;
  
  ResultSet rs = null;
  
  try {
  
  // Get a sax reader from the pool
  
  xmlReader = xmlReaders.take();
  
  con = DbConnectionManager.getConnection();
  
  pstmt = con.prepareStatement(LOAD_OFFLINE);
  
  pstmt.setString(1, username);
  
  rs = pstmt.executeQuery();
  
  while (rs.next()) {
  
  String msgXML = rs.getString(1);
  
  // 解析时间eg.Tue Apr 16 15:32:39 CST 2013
  
  Date creationDate = new Date(Long.parseLong(rs.getString(2)
  
  .trim()));
  
  OfflineMessage message;
  
  try {
  
  message = new OfflineMessage(creationDate, xmlReader.read(
  
  new StringReader(msgXML)).getRootElement());
  
  } catch (DocumentException e) {
  
  // Try again after removing invalid XML chars (e.g. )
  
  Matcher matcher = pattern.matcher(msgXML);
  
  if (matcher.find()) {
  
  msgXML = matcher.replaceAll("");
  
  }
  
  message = new OfflineMessage(creationDate, xmlReader.read(
  
  new StringReader(msgXML)).getRootElement());
  
  }
```
     // Add a delayed delivery (XEP-0203) element to the message.

     Element delay = message.addChildElement("delay",

             "urn:xmpp:delay");

     delay.addAttribute("from", XMPPServer.getInstance()

             .getServerInfo().getXMPPDomain());

     delay.addAttribute("stamp",

             XMPPDateTimeFormat.format(creationDate));

     // Add a legacy delayed delivery (XEP-0091) element to the

     // message. XEP is obsolete and support should be dropped in

     // future.

     delay = message.addChildElement("x", "jabber:x:delay");

     delay.addAttribute("from", XMPPServer.getInstance()

             .getServerInfo().getXMPPDomain());

     delay.addAttribute("stamp",

             XMPPDateTimeFormat.formatOld(creationDate));

     messages.add(message);

 }

 // Check if the offline messages loaded should be deleted, and that

 // there are

 // messages to delete.

 if (delete && !messages.isEmpty()) {

     PreparedStatement pstmt2 = null;

     try {

         pstmt2 = con.prepareStatement(DELETE_OFFLINE);

         pstmt2.setString(1, username);

         pstmt2.executeUpdate();

         removeUsernameFromSizeCache(username);

     } catch (Exception e) {

         Log.error("Error deleting offline messages of username: "

                 + username, e);

     } finally {

         DbConnectionManager.closeStatement(pstmt2);

     }

 }
```
  } catch (Exception e) {
  
  Log.error("Error retrieving offline messages of username: "
  
  + username, e);
  
  } finally {
  
  DbConnectionManager.closeConnection(rs, pstmt, con);
  
  // Return the sax reader to the pool
  
  if (xmlReader != null) {
  
  xmlReaders.add(xmlReader);
  
  }
  
  }
  
  return messages;
  
  }
/**
- Returns the offline message of the specified user with the given creation
- date. The returned message will NOT be deleted from the database.
- @param username
- ```
       the username of the user who's message you'd like to receive.
```
- @param creationDate
- ```
       the date when the offline message was stored in the database.
```
- @return the offline message of the specified user with the given creation
- ```
    stamp.
```
*/

public OfflineMessage getMessage(String username, Date creationDate) {

OfflineMessage message = null;

Connection con = null;

PreparedStatement pstmt = null;

ResultSet rs = null;

SAXReader xmlReader = null;

try {

// Get a sax reader from the pool

xmlReader = xmlReaders.take();

con = DbConnectionManager.getConnection();

pstmt = con.prepareStatement(LOAD_OFFLINE_MESSAGE);

pstmt.setString(1, username);

pstmt.setString(2, StringUtils.dateToMillis(creationDate));

rs = pstmt.executeQuery();

while (rs.next()) {

String msgXML = rs.getString(1);

message = new OfflineMessage(creationDate, xmlReader.read(

new StringReader(msgXML)).getRootElement());

// Add a delayed delivery (XEP-0203) element to the message.

Element delay = message.addChildElement("delay",

"urn:xmpp:delay");

delay.addAttribute("from", XMPPServer.getInstance()

.getServerInfo().getXMPPDomain());

delay.addAttribute("stamp",

XMPPDateTimeFormat.format(creationDate));

// Add a legacy delayed delivery (XEP-0091) element to the

// message. XEP is obsolete and support should be dropped in

// future.

delay = message.addChildElement("x", "jabber❌delay");

delay.addAttribute("from", XMPPServer.getInstance()

.getServerInfo().getXMPPDomain());

delay.addAttribute("stamp",

XMPPDateTimeFormat.formatOld(creationDate));

}

} catch (Exception e) {

Log.error("Error retrieving offline messages of username: "

+ username + " creationDate: " + creationDate, e);

} finally {

// Return the sax reader to the pool

if (xmlReader != null) {

xmlReaders.add(xmlReader);

}

DbConnectionManager.closeConnection(rs, pstmt, con);

}

return message;

}

/**
- Deletes all offline messages in the store for a user.
- @param username
- ```
       the username of the user who's messages are going to be
```
- ```
       deleted.
```
*/

public void deleteMessages(String username) {

Connection con = null;

PreparedStatement pstmt = null;

try {

con = DbConnectionManager.getConnection();

pstmt = con.prepareStatement(DELETE_OFFLINE);

pstmt.setString(1, username);

pstmt.executeUpdate();
```
     removeUsernameFromSizeCache(username);

 } catch (Exception e) {

     Log.error("Error deleting offline messages of username: "

             + username, e);

 } finally {

     DbConnectionManager.closeConnection(pstmt, con);

 }
```
}

private void removeUsernameFromSizeCache(String username) {

// Update the cached size if it exists.

if (sizeCache.containsKey(username)) {

sizeCache.remove(username);

}

}

/**
- Deletes the specified offline message in the store for a user. The way to
- identify the message to delete is based on the creationDate and username.
- @param username
- ```
       the username of the user who's message is going to be deleted.
```
- @param creationDate
- ```
       the date when the offline message was stored in the database.
```
*/

public void deleteMessage(String username, Date creationDate) {

Connection con = null;

PreparedStatement pstmt = null;

try {

con = DbConnectionManager.getConnection();

pstmt = con.prepareStatement(DELETE_OFFLINE_MESSAGE);

pstmt.setString(1, username);

pstmt.setString(2, StringUtils.dateToMillis(creationDate));

pstmt.executeUpdate();
```
     // Force a refresh for next call to getSize(username),

     // it's easier than loading the message to be deleted just

     // to update the cache.

     removeUsernameFromSizeCache(username);

 } catch (Exception e) {

     Log.error("Error deleting offline messages of username: "

             + username + " creationDate: " + creationDate, e);

 } finally {

     DbConnectionManager.closeConnection(pstmt, con);

 }
```
}

/**
- Returns the approximate size (in bytes) of the XML messages stored for a
- particular user.
- @param username
- ```
       the username of the user.
```
- @return the approximate size of stored messages (in bytes).
  
  */
  
  public int getSize(String username) {
  
  // See if the size is cached.
  
  if (sizeCache.containsKey(username)) {
  
  return sizeCache.get(username);
  
  }
  
  int size = 0;
  
  Connection con = null;
  
  PreparedStatement pstmt = null;
  
  ResultSet rs = null;
  
  try {
  
  con = DbConnectionManager.getConnection();
  
  pstmt = con.prepareStatement(SELECT_SIZE_OFFLINE);
  
  pstmt.setString(1, username);
  
  rs = pstmt.executeQuery();
  
  if (rs.next()) {
  
  size = rs.getInt(1);
  
  }
  
  // Add the value to cache.
  
  sizeCache.put(username, size);
  
  } catch (Exception e) {
  
  Log.error(LocaleUtils.getLocalizedString("admin.error"), e);
  
  } finally {
  
  DbConnectionManager.closeConnection(rs, pstmt, con);
  
  }
  
  return size;
  
  }
/**
- Returns the approximate size (in bytes) of the XML messages stored for
- all users.
- @return the approximate size of all stored messages (in bytes).
  
  */
  
  public int getSize() {
  
  int size = 0;
  
  Connection con = null;
  
  PreparedStatement pstmt = null;
  
  ResultSet rs = null;
  
  try {
  
  con = DbConnectionManager.getConnection();
  
  pstmt = con.prepareStatement(SELECT_SIZE_ALL_OFFLINE);
  
  rs = pstmt.executeQuery();
  
  if (rs.next()) {
  
  size = rs.getInt(1);
  
  }
  
  } catch (Exception e) {
  
  Log.error(LocaleUtils.getLocalizedString("admin.error"), e);
  
  } finally {
  
  DbConnectionManager.closeConnection(rs, pstmt, con);
  
  }
  
  return size;
  
  }
public void userCreated(User user, Map params) {

// Do nothing

}

public void userDeleting(User user, Map params) {

// Delete all offline messages of the user

deleteMessages(user.getUsername());

}

public void userModified(User user, Map params) {

// Do nothing

}

@Override

public void start() throws IllegalStateException {

super.start();

// Initialize the pool of sax readers

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

SAXReader xmlReader = new SAXReader();

xmlReader.setEncoding("UTF-8");

xmlReaders.add(xmlReader);

}

// Add this module as a user event listener so we can delete

// all offline messages when a user is deleted

UserEventDispatcher.addListener(this);

}

@Override

public void stop() {

super.stop();

// Clean up the pool of sax readers

xmlReaders.clear();

// Remove this module as a user event listener

UserEventDispatcher.removeListener(this);

}

}

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