原文:http://blog.csdn.net/smile326/article/details/52218264
1.场景需求
后台攻城狮和前端攻城狮一起开发时,经常受到前端攻城狮的骚扰,动不动就来一句,那谁,帮我看一下接口访问出什么错了。。。我刚刚上传的参数过来了吗。。。你返回的是什么。。。我请求过去了吗。。。
好吧,就是这样的一种情况,然后我希望让他们自己去看后台日志,而又不想给他们登陆服务器的权限TAT。那就想办法把访问日志实时输出到web页面,这样他们打开页面就可以了。
2.特别鸣谢
1)特别感谢http://blog.csdn.net/xiao__gui/article/details/50041673的启发,该文章中利用的是linux中的tail日志,本文即是受此启发,基本思路一模一样,感谢感谢。
2)感谢国产博客中各种websocket教程,获益颇多,本文其实也是一个websocket教程,只是稍作拓展。
3.进入正题
配置websocket,大部分web项目都会用到spring框架吧,所有这里贴spring websocket的配置,不用spring的请自行去掉spring部分。spring使用4.0以上,tomcat使用7.0.68版本。
1)pom.xml中包的引入:
<dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-annotations</artifactId> <version>2.3.0</version> </dependency> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-core</artifactId> <version>2.3.1</version> </dependency> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.3.3</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-messaging</artifactId> <version>4.0.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-websocket</artifactId> <version>4.0.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>4.0.5.RELEASE</version> </dependency> <dependency> <groupId>com.google.code.gson</groupId> <artifactId>gson</artifactId> <version>2.3.1</version> </dependency> <dependency> <groupId>javax.servlet</groupId> <artifactId>javax.servlet-api</artifactId> <version>3.1.0</version> <scope>provided</scope> </dependency>
2)websocket逻辑代码,需要一个config和一个handle
configuration:
package com.he.websocket; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.web.socket.config.annotation.EnableWebSocket; import org.springframework.web.socket.config.annotation.WebSocketConfigurer; import org.springframework.web.socket.config.annotation.WebSocketHandlerRegistry; import org.springframework.web.socket.server.support.HttpSessionHandshakeInterceptor; /** * WebScoket配置处理器 * @author he * @Date 2016年03月15日 下午1:15:09 */ @Configuration @EnableWebSocket public class WebsocketConfig implements WebSocketConfigurer { public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) { registry.addHandler(myHandler(), "/ws").addInterceptors(new HttpSessionHandshakeInterceptor()); registry.addHandler(myHandler(), "/ws/sockjs").addInterceptors(new HttpSessionHandshakeInterceptor()).withSockJS(); } @Bean public WebsocketHandler myHandler() { return new WebsocketHandler(); } }
handle:
package com.he.websocket; import java.io.IOException; import java.util.Date; import java.util.HashMap; import java.util.Iterator; import java.util.Map; import java.util.Map.Entry; import org.apache.log4j.Logger; import org.springframework.stereotype.Component; import org.springframework.web.socket.CloseStatus; import org.springframework.web.socket.TextMessage; import org.springframework.web.socket.WebSocketMessage; import org.springframework.web.socket.WebSocketSession; import org.springframework.web.socket.handler.TextWebSocketHandler; import com.google.gson.Gson; import com.google.gson.GsonBuilder; import com.he.entity.Message; @Component public class WebsocketHandler extends TextWebSocketHandler { protected static final Logger LOG = Logger.getLogger(WebsocketHandler.class); public static final Map<Object, WebSocketSession> userSocketSessionMap; static { userSocketSessionMap = new HashMap<Object, WebSocketSession>(); } /** * 建立连接后 */ public void afterConnectionEstablished(WebSocketSession session) throws Exception { String uid = (String) session.getAttributes().get("uid"); if (userSocketSessionMap.get(uid) == null) { userSocketSessionMap.put(uid, session); } LOG.warn("======建立连接完成======"); } /** * 消息处理,在客户端通过Websocket API发送的消息会经过这里,然后进行相应的处理 */ @Override public void handleMessage(WebSocketSession session, WebSocketMessage<?> message) throws Exception { if(message.getPayloadLength()==0)return; Message msg=new Gson().fromJson(message.getPayload().toString(),Message.class); String msgString = message.getPayload().toString(); LOG.warn("收到的消息是:" + msgString); LOG.warn("发送的对象是:" + msg.getTo()); msg.setDate(new Date()); sendMessageToUser(msg.getTo(), new TextMessage(new GsonBuilder().setDateFormat("yyyy-MM-dd HH:mm:ss").create().toJson(msg))); LOG.warn("======消息处理结束======"); } /** * 消息传输错误处理 */ public void handleTransportError(WebSocketSession session, Throwable exception) throws Exception { if (session.isOpen()) { session.close(); } Iterator<Entry<Object, WebSocketSession>> it = userSocketSessionMap .entrySet().iterator(); LOG.warn("======消息传输错误======"); // 移除Socket会话 while (it.hasNext()) { Entry<Object, WebSocketSession> entry = it.next(); if (entry.getValue().getId().equals(session.getId())) { userSocketSessionMap.remove(entry.getKey()); System.out.println("Socket会话已经移除:用户ID" + entry.getKey()); break; } } } /** * 关闭连接后 */ public void afterConnectionClosed(WebSocketSession session, CloseStatus closeStatus) throws Exception { LOG.warn("Websocket:" + session.getId() + "已经关闭"); Iterator<Entry<Object, WebSocketSession>> it = userSocketSessionMap .entrySet().iterator(); // 移除Socket会话 LOG.warn("======关闭连接======"); while (it.hasNext()) { Entry<Object, WebSocketSession> entry = it.next(); if (entry.getValue().getId().equals(session.getId())) { userSocketSessionMap.remove(entry.getKey()); LOG.warn("Socket会话已经移除:用户ID" + entry.getKey()); break; } } } public boolean supportsPartialMessages() { return false; } /** * 给所有在线用户发送消息 * * @param message * @throws IOException */ public void broadcast(final TextMessage message) throws IOException { Iterator<Entry<Object, WebSocketSession>> it = userSocketSessionMap .entrySet().iterator(); LOG.warn("======群发======"); // 多线程群发 while (it.hasNext()) { final Entry<Object, WebSocketSession> entry = it.next(); if (entry.getValue().isOpen()) { // entry.getValue().sendMessage(message); new Thread(new Runnable() { public void run() { try { if (entry.getValue().isOpen()) { entry.getValue().sendMessage(message); } } catch (IOException e) { e.printStackTrace(); } } }).start(); } } } /** * 给某个用户发送消息 * * @param userName * @param message * @throws IOException */ public void sendMessageToUser(String uid, TextMessage message) throws IOException { WebSocketSession session = userSocketSessionMap.get(uid); LOG.warn("======给某个用户发送消息======"); if (session != null && session.isOpen()) { session.sendMessage(message); } } }
3)web.xml中配置spring和springMVC,因为借助与springMVC来拦截处理websocket请求,如果用其他MVC框架,请自行替换。不想换也可以用springMVC,侵入性很低,并且本来就可以多种MVC共存。
<context-param> <param-name>contextConfigLocation</param-name> <param-value> /WEB-INF/classes/applicationContext.xml </param-value> </context-param> <servlet> <servlet-name>SpringMVC</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>/WEB-INF/classes/applicationContext.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>SpringMVC</servlet-name> <url-pattern>*.do</url-pattern> </servlet-mapping>
注意web.xml的头部:
<?xml version="1.0" encoding="UTF-8"?> <web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">
4)spring的xml文件中对websocket的配置:
<!-- websocket配置 --> <bean id="websocket" class="com.he.websocket.WebsocketHandler" /> <websocket:handlers> <websocket:mapping path="/ws.do" handler="websocket" /> <websocket:handshake-interceptors> <bean class="org.springframework.web.socket.server.support.HttpSessionHandshakeInterceptor" /> </websocket:handshake-interceptors> </websocket:handlers> <!-- 需要扫描的包--> <context:component-scan base-package="com.he.websocket.WebsocketConfig" /> <context:component-scan base-package="com.he.websocket.WebsocketHandler" />
注意spring的xml的头部:
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:websocket="http://www.springframework.org/schema/websocket" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd http://www.springframework.org/schema/websocket http://www.springframework.org/schema/websocket/spring-websocket.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd ">
5)日志接收页面:
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>tail log</title> <script src="//cdn.bootcss.com/jquery/2.1.4/jquery.js"></script> <style> html,body { height:100%; width:100%; } </style> </head> <body> <div id="log-container" style="height: 100%; overflow-y: scroll; background: #333; color: #aaa; padding: 10px;"> <div> </div> </div> </body> <script> $(document).ready(function() { // 指定websocket路径 var websocket = new WebSocket('ws://localhost:8080/websocket/ws.do'); websocket.onmessage = function(event) { // 接收服务端的实时日志并添加到HTML页面中 $("#log-container div").append(event.data + "<p> </p>"); // 滚动条滚动到最低部 $("#log-container").scrollTop($("#log-container div").height() - $("#log-container").height()); }; }); </script> </body> </html>
此页面打开时发送了一个websocket请求,ws.do,会被springMVC拦截处理。连接建立之后每当收到新的消息会追加到当前文本的末尾并换行(p标签用来换行)。
6)控制日志的实时打印示例:
PrintWriter out = response.getWriter(); MyWebSocketHandler.broadcast(new TextMessage(new GsonBuilder().setDateFormat("yyyy-MM-dd HH:mm:ss").create().toJson("访问test接口"))); out.println("访问test接口");
每次返回给前端某些值的时候通过一个广播将该值传送到web页面。如果不想广播,只需要在程序中对log的session进行特别的标签,然后定向传送即可。
效果示意图:浏览器输入localhost:8080/projectName/log.html,然后访问localhost:8080/projectName/test,每次访问test接口,网页上实时显示tomcat输出的日志。
4.备注:
需要完整代码留邮箱,看到就发送,发送的工程是一个基本的web工程,只集成spring websocket,本文的所有效果和引用都有。或者发邮件到smile326@qq.com提醒我。
本例中为方便消息的处理用到如下两个实体类(我也是沿用了别人教程代码):
Message.Java:
public class Message { //发送者 public Long from; //发送者名称 public String fromName; //接收者 public Long to; //发送的文本 public String text; //发送日期 public Date date; public Long getFrom() { return from; } public void setFrom(Long from) { this.from = from; } public Long getTo() { return to; } public void setTo(Long to) { this.to = to; } public String getText() { return text; } public void setText(String text) { this.text = text; } public String getFromName() { return fromName; } public void setFromName(String fromName) { this.fromName = fromName; } public Date getDate() { return date; } public void setDate(Date date) { this.date = date; } }
user.java:
public class User { private Long id; private String name; private String password; public Long getId() { return id; } public void setId(Long id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } }
应大家需求,完成工程的代码放在了github上面啦!传上去的代码进一步完善了一下,把建立连接的时候上传参数的问题处理了一下;把存放session的容器换成了线程安全型的!欢迎大家在线讨论!
https://github.com/smile326/springWebsockeForTomcatLog