ChatService.java

/*
 * Copyright (c) 2008-2017 the original author or authors.
 *
 * 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.cometd.examples;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;

import javax.inject.Inject;

import org.cometd.annotation.Configure;
import org.cometd.annotation.Listener;
import org.cometd.annotation.Service;
import org.cometd.annotation.Session;
import org.cometd.bayeux.client.ClientSessionChannel;
import org.cometd.bayeux.server.BayeuxServer;
import org.cometd.bayeux.server.ConfigurableServerChannel;
import org.cometd.bayeux.server.ServerMessage;
import org.cometd.bayeux.server.ServerSession;
import org.cometd.server.authorizer.GrantAuthorizer;
import org.cometd.server.filter.DataFilter;
import org.cometd.server.filter.DataFilterMessageListener;
import org.cometd.server.filter.JSONDataFilter;
import org.cometd.server.filter.NoMarkupFilter;

@Service("chat")
public class ChatService {
    private final ConcurrentMap<String, Map<String, String>> _members = new ConcurrentHashMap<>();
    @Inject
    private BayeuxServer _bayeux;
    @Session
    private ServerSession _session;

    @Configure({"/chat/**", "/members/**"})
    protected void configureChatStarStar(ConfigurableServerChannel channel) {
        DataFilterMessageListener noMarkup = new DataFilterMessageListener(new NoMarkupFilter(), new BadWordFilter());
        channel.addListener(noMarkup);
        channel.addAuthorizer(GrantAuthorizer.GRANT_ALL);
    }

    @Configure("/service/members")
    protected void configureMembers(ConfigurableServerChannel channel) {
        channel.addAuthorizer(GrantAuthorizer.GRANT_PUBLISH);
        channel.setPersistent(true);
    }

    @Listener("/service/members")
    public void handleMembership(ServerSession client, ServerMessage message) {
        Map<String, Object> data = message.getDataAsMap();
        final String room = ((String)data.get("room")).substring("/chat/".length());
        Map<String, String> roomMembers = _members.get(room);
        if (roomMembers == null) {
            Map<String, String> new_room = new ConcurrentHashMap<>();
            roomMembers = _members.putIfAbsent(room, new_room);
            if (roomMembers == null) {
                roomMembers = new_room;
            }
        }
        final Map<String, String> members = roomMembers;
        String userName = (String)data.get("user");
        members.put(userName, client.getId());
        client.addListener(new ServerSession.RemoveListener() {
            @Override
            public void removed(ServerSession session, boolean timeout) {
                members.values().remove(session.getId());
                broadcastMembers(room, members.keySet());
            }
        });

        broadcastMembers(room, members.keySet());
    }

    private void broadcastMembers(String room, Set<String> members) {
        // Broadcast the new members list
        ClientSessionChannel channel = _session.getLocalSession().getChannel("/members/" + room);
        channel.publish(members);
    }

    @Configure("/service/privatechat")
    protected void configurePrivateChat(ConfigurableServerChannel channel) {
        DataFilterMessageListener noMarkup = new DataFilterMessageListener(new NoMarkupFilter(), new BadWordFilter());
        channel.setPersistent(true);
        channel.addListener(noMarkup);
        channel.addAuthorizer(GrantAuthorizer.GRANT_PUBLISH);
    }

    @Listener("/service/privatechat")
    public void privateChat(ServerSession client, ServerMessage message) {
        Map<String, Object> data = message.getDataAsMap();
        String room = ((String)data.get("room")).substring("/chat/".length());
        Map<String, String> membersMap = _members.get(room);
        if (membersMap == null) {
            Map<String, String> new_room = new ConcurrentHashMap<>();
            membersMap = _members.putIfAbsent(room, new_room);
            if (membersMap == null) {
                membersMap = new_room;
            }
        }
        String[] peerNames = ((String)data.get("peer")).split(",");
        ArrayList<ServerSession> peers = new ArrayList<>(peerNames.length);

        for (String peerName : peerNames) {
            String peerId = membersMap.get(peerName);
            if (peerId != null) {
                ServerSession peer = _bayeux.getSession(peerId);
                if (peer != null) {
                    peers.add(peer);
                }
            }
        }

        if (peers.size() > 0) {
            Map<String, Object> chat = new HashMap<>();
            String text = (String)data.get("chat");
            chat.put("chat", text);
            chat.put("user", data.get("user"));
            chat.put("scope", "private");
            ServerMessage.Mutable forward = _bayeux.newMessage();
            forward.setChannel("/chat/" + room);
            forward.setId(message.getId());
            forward.setData(chat);

            // test for lazy messages
            if (text.lastIndexOf("lazy") > 0) {
                forward.setLazy(true);
            }

            for (ServerSession peer : peers) {
                if (peer != client) {
                    peer.deliver(_session, forward);
                }
            }
            client.deliver(_session, forward);
        }
    }

    class BadWordFilter extends JSONDataFilter {
        @Override
        protected Object filterString(String string) {
            if (string.contains("dang")) {
                throw new DataFilter.Abort();
            }
            return string;
        }
    }
}