/**
* $RCSfile$
* $Revision$
* $Date$
*
* Copyright 2005-2008 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.smackx.commands;
import org.jivesoftware.smack.*;
import org.jivesoftware.smack.filter.PacketFilter;
import org.jivesoftware.smack.filter.PacketTypeFilter;
import org.jivesoftware.smack.packet.IQ;
import org.jivesoftware.smack.packet.Packet;
import org.jivesoftware.smack.packet.PacketExtension;
import org.jivesoftware.smack.packet.XMPPError;
import org.jivesoftware.smack.util.StringUtils;
import org.jivesoftware.smackx.Form;
import org.jivesoftware.smackx.NodeInformationProvider;
import org.jivesoftware.smackx.ServiceDiscoveryManager;
import org.jivesoftware.smackx.commands.AdHocCommand.Action;
import org.jivesoftware.smackx.commands.AdHocCommand.Status;
import org.jivesoftware.smackx.packet.AdHocCommandData;
import org.jivesoftware.smackx.packet.DiscoverInfo;
import org.jivesoftware.smackx.packet.DiscoverInfo.Identity;
import org.jivesoftware.smackx.packet.DiscoverItems;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.WeakHashMap;
import java.util.concurrent.ConcurrentHashMap;
/**
* An AdHocCommandManager is responsible for keeping the list of available
* commands offered by a service and for processing commands requests.
*
* Pass in a Connection instance to
* {@link #getAddHocCommandsManager(org.jivesoftware.smack.Connection)} in order to
* get an instance of this class.
*
* @author Gabriel Guardincerri
*/
public class AdHocCommandManager {
private static final String DISCO_NAMESPACE = "http://jabber.org/protocol/commands";
private static final String discoNode = DISCO_NAMESPACE;
/**
* The session time out in seconds.
*/
private static final int SESSION_TIMEOUT = 2 * 60;
/**
* Map a Connection with it AdHocCommandManager. This map have a key-value
* pair for every active connection.
*/
private static Map<Connection, AdHocCommandManager> instances =
new ConcurrentHashMap<Connection, AdHocCommandManager>();
/**
* Register the listener for all the connection creations. When a new
* connection is created a new AdHocCommandManager is also created and
* related to that connection.
*/
static {
Connection.addConnectionCreationListener(new ConnectionCreationListener() {
public void connectionCreated(Connection connection) {
new AdHocCommandManager(connection);
}
});
}
/**
* Returns the <code>AdHocCommandManager</code> related to the
* <code>connection</code>.
*
* @param connection the XMPP connection.
* @return the AdHocCommandManager associated with the connection.
*/
public static AdHocCommandManager getAddHocCommandsManager(Connection connection) {
return instances.get(connection);
}
/**
* Thread that reaps stale sessions.
*/
private Thread sessionsSweeper;
/**
* The Connection that this instances of AdHocCommandManager manages
*/
private Connection connection;
/**
* Map a command node with its AdHocCommandInfo. Note: Key=command node,
* Value=command. Command node matches the node attribute sent by command
* requesters.
*/
private Map<String, AdHocCommandInfo> commands = Collections
.synchronizedMap(new WeakHashMap<String, AdHocCommandInfo>());
/**
* Map a command session ID with the instance LocalCommand. The LocalCommand
* is the an objects that has all the information of the current state of
* the command execution. Note: Key=session ID, Value=LocalCommand. Session
* ID matches the sessionid attribute sent by command responders.
*/
private Map<String, LocalCommand> executingCommands = new ConcurrentHashMap<String, LocalCommand>();
private AdHocCommandManager(Connection connection) {
super();
this.connection = connection;
init();
}
/**
* Registers a new command with this command manager, which is related to a
* connection. The <tt>node</tt> is an unique identifier of that command for
* the connection related to this command manager. The <tt>name</tt> is the
* human readable name of the command. The <tt>class</tt> is the class of
* the command, which must extend {@link LocalCommand} and have a default
* constructor.
*
* @param node the unique identifier of the command.
* @param name the human readable name of the command.
* @param clazz the class of the command, which must extend {@link LocalCommand}.
*/
public void registerCommand(String node, String name, final Class<? extends LocalCommand> clazz) {
registerCommand(node, name, new LocalCommandFactory() {
public LocalCommand getInstance() throws InstantiationException, IllegalAccessException {
return clazz.newInstance();
}
});
}
/**
* Registers a new command with this command manager, which is related to a
* connection. The <tt>node</tt> is an unique identifier of that
* command for the connection related to this command manager. The <tt>name</tt>
* is the human readeale name of the command. The <tt>factory</tt> generates
* new instances of the command.
*
* @param node the unique identifier of the command.
* @param name the human readable name of the command.
* @param factory a factory to create new instances of the command.
*/
public void registerCommand(String node, final String name, LocalCommandFactory factory) {
AdHocCommandInfo commandInfo = new AdHocCommandInfo(node, name, connection.getUser(), factory);
commands.put(node, commandInfo);
// Set the NodeInformationProvider that will provide information about
// the added command
ServiceDiscoveryManager.getInstanceFor(connection).setNodeInformationProvider(node,
new NodeInformationProvider() {
public List<DiscoverItems.Item> getNodeItems() {
return null;
}
public List<String> getNodeFeatures() {
List<String> answer = new ArrayList<String>();
answer.add(DISCO_NAMESPACE);
// TODO: check if this service is provided by the
// TODO: current connection.
answer.add("jabber:x:data");
return answer;
}
public List<DiscoverInfo.Identity> getNodeIdentities() {
List<DiscoverInfo.Identity> answer = new ArrayList<DiscoverInfo.Identity>();
DiscoverInfo.Identity identity = new DiscoverInfo.Identity(
"automation", name, "command-node");
answer.add(identity);
return answer;
}
@Override
public List<PacketExtension> getNodePacketExtensions() {
return null;
}
});
}
/**
* Discover the commands of an specific JID. The <code>jid</code> is a
* full JID.
*
* @param jid the full JID to retrieve the commands for.
* @return the discovered items.
* @throws XMPPException if the operation failed for some reason.
*/
public DiscoverItems discoverCommands(String jid) throws XMPPException {
ServiceDiscoveryManager serviceDiscoveryManager = ServiceDiscoveryManager
.getInstanceFor(connection);
return serviceDiscoveryManager.discoverItems(jid, discoNode);
}
/**
* Publish the commands to an specific JID.
*
* @param jid the full JID to publish the commands to.
* @throws XMPPException if the operation failed for some reason.
*/
public void publishCommands(String jid) throws XMPPException {
ServiceDiscoveryManager serviceDiscoveryManager = ServiceDiscoveryManager
.getInstanceFor(connection);
// Collects the commands to publish as items
DiscoverItems discoverItems = new DiscoverItems();
Collection<AdHocCommandInfo> xCommandsList = getRegisteredCommands();
for (AdHocCommandInfo info : xCommandsList) {
DiscoverItems.Item item = new DiscoverItems.Item(info.getOwnerJID());
item.setName(info.getName());
item.setNode(info.getNode());
discoverItems.addItem(item);
}
serviceDiscoveryManager.publishItems(jid, discoNode, discoverItems);
}
/**
* Returns a command that represents an instance of a command in a remote
* host. It is used to execute remote commands. The concept is similar to
* RMI. Every invocation on this command is equivalent to an invocation in
* the remote command.
*
* @param jid the full JID of the host of the remote command
* @param node the identifier of the command
* @return a local instance equivalent to the remote command.
*/
public RemoteCommand getRemoteCommand(String jid, String node) {
return new RemoteCommand(connection, node, jid);
}
/**
* <ul>
* <li>Adds listeners to the connection</li>
* <li>Registers the ad-hoc command feature to the ServiceDiscoveryManager</li>
* <li>Registers the items of the feature</li>
* <li>Adds packet listeners to handle execution requests</li>
* <li>Creates and start the session sweeper</li>
* </ul>
*/
private void init() {
// Register the new instance and associate it with the connection
instances.put(connection, this);
// Add a listener to the connection that removes the registered instance
// when the connection is closed
connection.addConnectionListener(new ConnectionListener() {
public void connectionClosed() {
// Unregister this instance since the connection has been closed
instances.remove(connection);
}
public void connectionClosedOnError(Exception e) {
// Unregister this instance since the connection has been closed
instances.remove(connection);
}
public void reconnectionSuccessful() {
// Register this instance since the connection has been
// reestablished
instances.put(connection, AdHocCommandManager.this);
}
public void reconnectingIn(int seconds) {
// Nothing to do
}
public void reconnectionFailed(Exception e) {
// Nothing to do
}
});
// Add the feature to the service discovery manage to show that this
// connection supports the AdHoc-Commands protocol.
// This information will be used when another client tries to
// discover whether this client supports AdHoc-Commands or not.
ServiceDiscoveryManager.getInstanceFor(connection).addFeature(
DISCO_NAMESPACE);
// Set the NodeInformationProvider that will provide information about
// which AdHoc-Commands are registered, whenever a disco request is
// received
ServiceDiscoveryManager.getInstanceFor(connection)
.setNodeInformationProvider(discoNode,
new NodeInformationProvider() {
public List<DiscoverItems.Item> getNodeItems() {
List<DiscoverItems.Item> answer = new ArrayList<DiscoverItems.Item>();
Collection<AdHocCommandInfo> commandsList = getRegisteredCommands();
for (AdHocCommandInfo info : commandsList) {
DiscoverItems.Item item = new DiscoverItems.Item(
info.getOwnerJID());
item.setName(info.getName());
item.setNode(info.getNode());
answer.add(item);
}
return answer;
}
public List<String> getNodeFeatures() {
return null;
}
public List<Identity> getNodeIdentities() {
return null;
}
@Override
public List<PacketExtension> getNodePacketExtensions() {
return null;
}
});
// The packet listener and the filter for processing some AdHoc Commands
// Packets
PacketListener listener = new PacketListener() {
public void processPacket(Packet packet) {
AdHocCommandData requestData = (AdHocCommandData) packet;
processAdHocCommand(requestData);
}
};
PacketFilter filter = new PacketTypeFilter(AdHocCommandData.class);
connection.addPacketListener(listener, filter);
sessionsSweeper = null;
}
/**
* Process the AdHoc-Command packet that request the execution of some
* action of a command. If this is the first request, this method checks,
* before executing the command, if:
* <ul>
* <li>The requested command exists</li>
* <li>The requester has permissions to execute it</li>
* <li>The command has more than one stage, if so, it saves the command and
* session ID for further use</li>
* </ul>
*
* <br>
* <br>
* If this is not the first request, this method checks, before executing
* the command, if:
* <ul>
* <li>The session ID of the request was stored</li>
* <li>The session life do not exceed the time out</li>
* <li>The action to execute is one of the available actions</li>
* </ul>
*
* @param requestData
* the packet to process.
*/
private void processAdHocCommand(AdHocCommandData requestData) {
// Only process requests of type SET
if (requestData.getType() != IQ.Type.SET) {
return;
}
// Creates the response with the corresponding data
AdHocCommandData response = new AdHocCommandData();
response.setTo(requestData.getFrom());
response.setPacketID(requestData.getPacketID());
response.setNode(requestData.getNode());
response.setId(requestData.getTo());
String sessionId = requestData.getSessionID();
String commandNode = requestData.getNode();
if (sessionId == null) {
// A new execution request has been received. Check that the
// command exists
if (!commands.containsKey(commandNode)) {
// Requested command does not exist so return
// item_not_found error.
respondError(response, XMPPError.Condition.item_not_found);
return;
}
// Create new session ID
sessionId = StringUtils.randomString(15);
try {
// Create a new instance of the command with the
// corresponding sessioid
LocalCommand command = newInstanceOfCmd(commandNode, sessionId);
response.setType(IQ.Type.RESULT);
command.setData(response);
// Check that the requester has enough permission.
// Answer forbidden error if requester permissions are not
// enough to execute the requested command
if (!command.hasPermission(requestData.getFrom())) {
respondError(response, XMPPError.Condition.forbidden);
return;
}
Action action = requestData.getAction();
// If the action is unknown then respond an error.
if (action != null && action.equals(Action.unknown)) {
respondError(response, XMPPError.Condition.bad_request,
AdHocCommand.SpecificErrorCondition.malformedAction);
return;
}
// If the action is not execute, then it is an invalid action.
if (action != null && !action.equals(Action.execute)) {
respondError(response, XMPPError.Condition.bad_request,
AdHocCommand.SpecificErrorCondition.badAction);
return;
}
// Increase the state number, so the command knows in witch
// stage it is
command.incrementStage();
// Executes the command
command.execute();
if (command.isLastStage()) {
// If there is only one stage then the command is completed
response.setStatus(Status.completed);
}
else {
// Else it is still executing, and is registered to be
// available for the next call
response.setStatus(Status.executing);
executingCommands.put(sessionId, command);
// See if the session reaping thread is started. If not, start it.
if (sessionsSweeper == null) {
sessionsSweeper = new Thread(new Runnable() {
public void run() {
while (true) {
for (String sessionId : executingCommands.keySet()) {
LocalCommand command = executingCommands.get(sessionId);
// Since the command could be removed in the meanwhile
// of getting the key and getting the value - by a
// processed packet. We must check if it still in the
// map.
if (command != null) {
long creationStamp = command.getCreationDate();
// Check if the Session data has expired (default is
// 10 minutes)
// To remove it from the session list it waits for
// the double of the of time out time. This is to
// let
// the requester know why his execution request is
// not accepted. If the session is removed just
// after the time out, then whe the user request to
// continue the execution he will recieved an
// invalid session error and not a time out error.
if (System.currentTimeMillis() - creationStamp > SESSION_TIMEOUT * 1000 * 2) {
// Remove the expired session
executingCommands.remove(sessionId);
}
}
}
try {
Thread.sleep(1000);
}
catch (InterruptedException ie) {
// Ignore.
}
}
}
});
sessionsSweeper.setDaemon(true);
sessionsSweeper.start();
}
}
// Sends the response packet
connection.sendPacket(response);
}
catch (XMPPException e) {
// If there is an exception caused by the next, complete,
// prev or cancel method, then that error is returned to the
// requester.
XMPPError error = e.getXMPPError();
// If the error type is cancel, then the execution is
// canceled therefore the status must show that, and the
// command be removed from the executing list.
if (XMPPError.Type.CANCEL.equals(error.getType())) {
response.setStatus(Status.canceled);
executingCommands.remove(sessionId);
}
respondError(response, error);
e.printStackTrace();
}
}
else {
LocalCommand command = executingCommands.get(sessionId);
// Check that a command exists for the specified sessionID
// This also handles if the command was removed in the meanwhile
// of getting the key and the value of the map.
if (command == null) {
respondError(response, XMPPError.Condition.bad_request,
AdHocCommand.SpecificErrorCondition.badSessionid);
return;
}
// Check if the Session data has expired (default is 10 minutes)
long creationStamp = command.getCreationDate();
if (System.currentTimeMillis() - creationStamp > SESSION_TIMEOUT * 1000) {
// Remove the expired session
executingCommands.remove(sessionId);
// Answer a not_allowed error (session-expired)
respondError(response, XMPPError.Condition.not_allowed,
AdHocCommand.SpecificErrorCondition.sessionExpired);
return;
}
/*
* Since the requester could send two requests for the same
* executing command i.e. the same session id, all the execution of
* the action must be synchronized to avoid inconsistencies.
*/
synchronized (command) {
Action action = requestData.getAction();
// If the action is unknown the respond an error
if (action != null && action.equals(Action.unknown)) {
respondError(response, XMPPError.Condition.bad_request,
AdHocCommand.SpecificErrorCondition.malformedAction);
return;
}
// If the user didn't specify an action or specify the execute
// action then follow the actual default execute action
if (action == null || Action.execute.equals(action)) {
action = command.getExecuteAction();
}
// Check that the specified action was previously
// offered
if (!command.isValidAction(action)) {
respondError(response, XMPPError.Condition.bad_request,
AdHocCommand.SpecificErrorCondition.badAction);
return;
}
try {
// TODO: Check that all the requierd fields of the form are
// TODO: filled, if not throw an exception. This will simplify the
// TODO: construction of new commands
// Since all errors were passed, the response is now a
// result
response.setType(IQ.Type.RESULT);
// Set the new data to the command.
command.setData(response);
if (Action.next.equals(action)) {
command.incrementStage();
command.next(new Form(requestData.getForm()));
if (command.isLastStage()) {
// If it is the last stage then the command is
// completed
response.setStatus(Status.completed);
}
else {
// Otherwise it is still executing
response.setStatus(Status.executing);
}
}
else if (Action.complete.equals(action)) {
command.incrementStage();
command.complete(new Form(requestData.getForm()));
response.setStatus(Status.completed);
// Remove the completed session
executingCommands.remove(sessionId);
}
else if (Action.prev.equals(action)) {
command.decrementStage();
command.prev();
}
else if (Action.cancel.equals(action)) {
command.cancel();
response.setStatus(Status.canceled);
// Remove the canceled session
executingCommands.remove(sessionId);
}
connection.sendPacket(response);
}
catch (XMPPException e) {
// If there is an exception caused by the next, complete,
// prev or cancel method, then that error is returned to the
// requester.
XMPPError error = e.getXMPPError();
// If the error type is cancel, then the execution is
// canceled therefore the status must show that, and the
// command be removed from the executing list.
if (XMPPError.Type.CANCEL.equals(error.getType())) {
response.setStatus(Status.canceled);
executingCommands.remove(sessionId);
}
respondError(response, error);
e.printStackTrace();
}
}
}
}
/**
* Responds an error with an specific condition.
*
* @param response the response to send.
* @param condition the condition of the error.
*/
private void respondError(AdHocCommandData response,
XMPPError.Condition condition) {
respondError(response, new XMPPError(condition));
}
/**
* Responds an error with an specific condition.
*
* @param response the response to send.
* @param condition the condition of the error.
* @param specificCondition the adhoc command error condition.
*/
private void respondError(AdHocCommandData response, XMPPError.Condition condition,
AdHocCommand.SpecificErrorCondition specificCondition)
{
XMPPError error = new XMPPError(condition);
error.addExtension(new AdHocCommandData.SpecificError(specificCondition));
respondError(response, error);
}
/**
* Responds an error with an specific error.
*
* @param response the response to send.
* @param error the error to send.
*/
private void respondError(AdHocCommandData response, XMPPError error) {
response.setType(IQ.Type.ERROR);
response.setError(error);
connection.sendPacket(response);
}
/**
* Creates a new instance of a command to be used by a new execution request
*
* @param commandNode the command node that identifies it.
* @param sessionID the session id of this execution.
* @return the command instance to execute.
* @throws XMPPException if there is problem creating the new instance.
*/
private LocalCommand newInstanceOfCmd(String commandNode, String sessionID)
throws XMPPException
{
AdHocCommandInfo commandInfo = commands.get(commandNode);
LocalCommand command;
try {
command = (LocalCommand) commandInfo.getCommandInstance();
command.setSessionID(sessionID);
command.setName(commandInfo.getName());
command.setNode(commandInfo.getNode());
}
catch (InstantiationException e) {
e.printStackTrace();
throw new XMPPException(new XMPPError(
XMPPError.Condition.interna_server_error));
}
catch (IllegalAccessException e) {
e.printStackTrace();
throw new XMPPException(new XMPPError(
XMPPError.Condition.interna_server_error));
}
return command;
}
/**
* Returns the registered commands of this command manager, which is related
* to a connection.
*
* @return the registered commands.
*/
private Collection<AdHocCommandInfo> getRegisteredCommands() {
return commands.values();
}
/**
* Stores ad-hoc command information.
*/
private static class AdHocCommandInfo {
private String node;
private String name;
private String ownerJID;
private LocalCommandFactory factory;
public AdHocCommandInfo(String node, String name, String ownerJID,
LocalCommandFactory factory)
{
this.node = node;
this.name = name;
this.ownerJID = ownerJID;
this.factory = factory;
}
public LocalCommand getCommandInstance() throws InstantiationException,
IllegalAccessException
{
return factory.getInstance();
}
public String getName() {
return name;
}
public String getNode() {
return node;
}
public String getOwnerJID() {
return ownerJID;
}
}
}