Preface

The introduction of WebSocket in Springboot will not be repeated here. There are more introductions on the Internet. This paper mainly solves the problem of broadcasting messages (for a topic) and sending messages to specific users. No more nonsense, start our realization.

Environmental Science

Only the core technical points are listed here.

Realization

socket core configuration container

package com.ricky.websocket;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.messaging.simp.config.MessageBrokerRegistry;
import org.springframework.web.socket.config.annotation.AbstractWebSocketMessageBrokerConfigurer;
import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker;
import org.springframework.web.socket.config.annotation.StompEndpointRegistry;

/**
 * socket Core Configuration Container
 */
@Configuration
@EnableWebSocketMessageBroker
public class WebSocketConfig extends AbstractWebSocketMessageBrokerConfigurer {

    @Override
    public void configureMessageBroker(MessageBrokerRegistry config) {
        config.enableSimpleBroker("/topic");// / users default notification
        config.setApplicationDestinationPrefixes("/app");
    }

    @Override
    public void registerStompEndpoints(StompEndpointRegistry registry) {
            registry.addEndpoint("/ricky-websocket").withSockJS();
    }


    @Bean
    public SocketSessionRegistry SocketSessionRegistry(){
        return new SocketSessionRegistry();
    }
    @Bean
    public STOMPConnectEventListener STOMPConnectEventListener(){
        return new STOMPConnectEventListener();
    }
}

User session record class

package com.ricky.websocket;

import org.springframework.util.Assert;

import java.util.Collections;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.CopyOnWriteArraySet;

/**
 * Created by baiguantao on 2017/8/4.
 * User session record class
 */
public class SocketSessionRegistry{
    //this map save every session
    //This collection stores session
    private final ConcurrentMap<String, Set<String>> userSessionIds = new ConcurrentHashMap();
    private final Object lock = new Object();

    public SocketSessionRegistry() {
    }

    /**
     *
     * Get session Id
     * @param user
     * @return
     */
    public Set<String> getSessionIds(String user) {
        Set set = (Set)this.userSessionIds.get(user);
        return set != null?set: Collections.emptySet();
    }

    /**
     * Get all session s
     * @return
     */
    public ConcurrentMap<String, Set<String>> getAllSessionIds() {
        return this.userSessionIds;
    }

    /**
     * register session
     * @param user
     * @param sessionId
     */
    public void registerSessionId(String user, String sessionId) {
        Assert.notNull(user, "User must not be null");
        Assert.notNull(sessionId, "Session ID must not be null");
        Object var3 = this.lock;
        synchronized(this.lock) {
            Object set = (Set)this.userSessionIds.get(user);
            if(set == null) {
                set = new CopyOnWriteArraySet();
                this.userSessionIds.put(user, (Set<String>) set);
            }

            ((Set)set).add(sessionId);
        }
    }

    public void unregisterSessionId(String userName, String sessionId) {
        Assert.notNull(userName, "User Name must not be null");
        Assert.notNull(sessionId, "Session ID must not be null");
        Object var3 = this.lock;
        synchronized(this.lock) {
            Set set = (Set)this.userSessionIds.get(userName);
            if(set != null && set.remove(sessionId) && set.isEmpty()) {
                this.userSessionIds.remove(userName);
            }

        }
    }
}

STOMP listening class

package com.ricky.websocket;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationListener;
import org.springframework.messaging.simp.stomp.StompHeaderAccessor;
import org.springframework.web.socket.messaging.SessionConnectEvent;

/**
 * Created by baiguantao on 2017/8/4.
 * STOMP Monitoring category
 * Used for session registration and key value acquisition
 */
public class STOMPConnectEventListener  implements ApplicationListener<SessionConnectEvent> {

    @Autowired
    SocketSessionRegistry webAgentSessionRegistry;

    @Override
    public void onApplicationEvent(SessionConnectEvent event) {
        StompHeaderAccessor sha = StompHeaderAccessor.wrap(event.getMessage());
        //login get from browser
        String agentId = sha.getNativeHeader("login").get(0);
        String sessionId = sha.getSessionId();
        webAgentSessionRegistry.registerSessionId(agentId,sessionId);
    }
}

Chat Controller

package com.ricky.websocket;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.messaging.MessageHeaders;
import org.springframework.messaging.handler.annotation.MessageMapping;
import org.springframework.messaging.simp.SimpMessageHeaderAccessor;
import org.springframework.messaging.simp.SimpMessageType;
import org.springframework.messaging.simp.SimpMessagingTemplate;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import javax.servlet.http.HttpServletRequest;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

/**
 * Chat Controller
 */
@Controller
public class GreetingController {
    /**session Operational class*/
    @Autowired
    SocketSessionRegistry webAgentSessionRegistry;
    /**Message Sending Tool*/
    @Autowired
    private SimpMessagingTemplate template;

    @RequestMapping(value = "/index")
    public  String index(){
        return "/index";
    }
    @RequestMapping(value = "/msg/message")
    public  String ToMessage(){
        return "/message";
    }
    @RequestMapping(value = "/msg/messaget2")
    public  String ToMessaget2(){
        return "/messaget2";
    }

    /**
     * User Broadcasting
     * Send Message Broadcasting for Internal Send Use
     * @param request
     * @return
     */
    @GetMapping(value = "/msg/sendcommuser")
    public  @ResponseBody
    OutMessage SendToCommUserMessage(HttpServletRequest request){
        List<String> keys=webAgentSessionRegistry.getAllSessionIds().entrySet()
                .stream().map(Map.Entry::getKey)
                .collect(Collectors.toList());
        Date date=new Date();
        keys.forEach(x->{
            String sessionId=webAgentSessionRegistry.getSessionIds(x).stream().findFirst().get().toString();
            template.convertAndSendToUser(sessionId,"/topic/greetings",new OutMessage("commmsg: allsend, " + "send  comm" +date.getTime()+ "!"),createHeaders(sessionId));

        });
         return new OutMessage("sendcommuser, " + new Date() + "!");
    }




    /**
     * The same sending message is just that the ws version http request is not accessible
     * Send messages based on user key
     * @param message
     * @return
     * @throws Exception
     */
    @MessageMapping("/msg/hellosingle")
    public void greeting2(InMessage message) throws Exception {
        Map<String,String> params = new HashMap(1);
        params.put("test","test");
        //There's no verification here.
        String sessionId=webAgentSessionRegistry.getSessionIds(message.getId()).stream().findFirst().get();
        template.convertAndSendToUser(sessionId,"/topic/greetings",new OutMessage("single send to: "+message.getId()+", from:" + message.getName() + "!"),createHeaders(sessionId));
    }
    private MessageHeaders createHeaders(String sessionId) {
        SimpMessageHeaderAccessor headerAccessor = SimpMessageHeaderAccessor.create(SimpMessageType.MESSAGE);
        headerAccessor.setSessionId(sessionId);
        headerAccessor.setLeaveMutable(true);
        return headerAccessor.getMessageHeaders();
    }

}

Other

Front end part

<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.w3.org/1999/xhtml">
<link href="/webjars/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet">
<script src="/webjars/jquery/3.1.0/jquery.min.js"></script>
<script src="/webjars/sockjs-client/1.0.2/sockjs.min.js"></script>
<script src="/webjars/stomp-websocket/2.3.3/stomp.min.js"></script>
<body>
    <blockquote class="layui-elem-quote">/user/topic-message</blockquote>

    <div id="main-content" class="container">
        <div class="row">
            <div class="col-md-6">
                <form class="form-inline">
                    <div class="form-group">
                        <label for="connect">WebSocket connection:</label>
                        <button id="connect" class="btn btn-default" type="submit">Connect</button>
                        <button id="disconnect" class="btn btn-default" type="submit" disabled="disabled">Disconnect
                        </button>

                    </div>
                </form>
            </div>
            <div class="col-md-6">
                <form class="form-inline">
                    <div class="form-group">
                        <label for="name">What is your name?</label>
                        <input type="text" id="name" class="form-control" placeholder="Your name here...">
                    </div>
                    <button id="send" class="btn btn-default" type="submit">Send</button>
                </form>
            </div>
        </div>
        <div class="row">
            <div class="col-md-12">
                <table id="conversation" class="table table-striped">
                    <thead>
                    <tr>
                        <th>Greetings</th>
                    </tr>
                    </thead>
                    <tbody id="greetings">
                    </tbody>
                </table>
            </div>
        </div>
        </form>
    </div>

    <script>
        //  /msg/sendcommuser
        var stompClient = null;
        //Pass the user key value
        var login = "ricky";
        function setConnected(connected) {
            $("#connect").prop("disabled", connected);
            $("#disconnect").prop("disabled", !connected);
            if (connected) {
                $("#conversation").show();
            }
            else {
                $("#conversation").hide();
            }
            $("#greetings").html("");
        }

        function connect() {
            var socket = new SockJS('/ricky-websocket');
            stompClient = Stomp.over(socket);
            stompClient.connect({login:login}, function (frame) {
                setConnected(true);
                console.log('Connected: ' + frame);
                stompClient.subscribe('/user/topic/greetings', function (greeting) {
                    showGreeting(JSON.parse(greeting.body).content);
                });
            });
        }

        function disconnect() {
            if (stompClient != null) {
                stompClient.disconnect();
            }
            setConnected(false);
            console.log("Disconnected");
        }

        function sendName() {
            stompClient.send("/app/msg/hellosingle", {}, JSON.stringify({'name': $("#name").val(),'id':'rickyt2'}));
        }


        function showGreeting(message) {
            $("#greetings").append("<tr><td>" + message + "</td></tr>");
        }

        $(function () {
            $("form").on('submit', function (e) {
                e.preventDefault();
            });
            $( "#connect" ).click(function() { connect(); });
            $( "#disconnect" ).click(function() { disconnect(); });
            $( "#send" ).click(function() { sendName(); });
        });
    </script>
</body>
</html>

Demonstration

homepage

ricky users

rickyt2 user

Sending public messages

Click the public message button on the home page to send the public message. If you want to send it again, refresh the public message page.

Explain

Pits encountered

webjars 404

By default, the relevant plug-ins are introduced as follows:

<link href="/webjars/bootstrap/css/bootstrap.min.css" rel="stylesheet">

But found that no, even with the relevant plug-in (locator), not, and then look at the source code, found that there are 3.3.7 directories, need to add version paths.

<link href="/webjars/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet">

Message User Problem

This pit is about the path, and a little partner may wonder why my subscription has a prefix of / user. This is actually because we use the convertAndSendToUser source code of SimpMessaging Template. The default prefix is user, so we add / user prefix, which is also the core of messages sent to specific users.

Refer to destination in SimpMessaging Template:

 public void send(D destination, Message<?> message) {
        this.doSend(destination, message);
    }

epilogue

Finally, once into the programming deep like the sea, from then on white teenagers.

Attached demo address: SpringBootWebSocket

author

ricky Exchange Group: 2449 30845