netty 案例,netty4.1 中级拓展篇九《Netty 集群部署实现跨服务端通信的落地方案》
前言介绍
Netty的性能非常好,在一些小型用户体量的socket服务内,仅部署单台机器就可以满足业务需求。但当遇到一些中大型用户体量的服务时,就需要考虑讲Netty按照集群方式部署,以更好的满足业务诉求。但Netty部署集群后都会遇到跨服务端怎么通信,也就是有集群服务X和Y,用户A链接服务X,用户B链接服务Y,那么他们都不在一个服务内怎么通信?本章节将介绍一种实现方式案例,以满足跨服务之间的用户通信。但实际场景中需要进行一些扩展性改造,案例仅将核心主干思路做以实现,只是一种思路指导,并不能直接使用于业务开发。
本章知识点
跨服务之间案例采用redis的发布和订阅进行传递消息,如果你是大型服务可以使用zookeeper
用户A在发送消息给用户B时候,需要传递B的channeId,以用于服务端进行查找channeId所属是否自己的服务内
单台机器也可以启动多个Netty服务,程序内会自动寻找可用端口
环境准备
1、jdk1.8【jdk1.7以下只能部分支持netty】
2、Netty4.1.36.Final【netty3.x 4.x 5每次的变化较大,接口类名也随着变化】
3、NetAssist 网络调试助手,可以从网上下载也可以联系我,微信公众号:bugstack虫洞栈 | 关注回复你的邮箱
4、redis服务端,案例采用windows版本,按需从官网下载即可
代码示例
itstack-demo-rpc-2-09└── src └── main │ ├── java │ │ └── org.itstack.demo.netty │ │ ├── domain │ │ │ ├── EasyResult.java │ │ │ ├── MsgAgreement.java │ │ │ ├── ServerInfo.java │ │ │ └── UserChannelInfo.java │ │ ├── redis │ │ │ ├── config │ │ │ │ ├── PublisherConfig.java │ │ │ │ └── ReceiverConfig.java │ │ │ ├── AbstractReceiver.java │ │ │ ├── MsgAgreementReceiver.java │ │ │ ├── Publisher.java │ │ │ └── RedisUtil.java │ │ ├── server │ │ │ ├── MyChannelInitializer.java │ │ │ ├── MyServerHandler.java │ │ │ └── NettyServer.java │ │ ├── service │ │ │ └── ExtServerService.java │ │ ├── util │ │ │ ├── CacheUtil.java │ │ │ ├── MsgUtil.java │ │ │ └── NetUtil.java │ │ ├── web │ │ │ └── NettyController.java │ │ └── Application.java │ ├── resources │ │ └── application.yml │ └── webapp │ ├── res │ └── WEB-INF │ └── index.jsp └── test └── java └── org.itstack.demo.test └── ApiTest.java
演示讲解部分重点代码块,完整代码下载,关注公众号;bugstack虫洞栈 | 回复:netty案例源码
>domain/MsgAgreement.java | 定义信息传输协议,这个看似简单但非常重要,每一个通信的根本就是定义传输协议信息
/** * 消息协议 * 虫洞栈:https://bugstack.cn * 公众号:bugstack虫洞栈 {关注获取学习源码} * 虫洞群:①群5398358 ②群5360692 * Create by fuzhengwei on 2019 */public class MsgAgreement { private String toChannelId; //发送给某人,某人channelId private String content; //消息内容 public MsgAgreement() { } public MsgAgreement(String toChannelId, String content) { this.toChannelId = toChannelId; this.content = content; } public String getToChannelId() { return toChannelId; } public void setToChannelId(String toChannelId) { this.toChannelId = toChannelId; } public String getContent() { return content; } public void setContent(String content) { this.content = content; } }
>redis/config/PublisherConfig.java | redis消息发布者,集成与SpringBoot的配置方式
/** * 发布者 * 虫洞栈:https://bugstack.cn * 公众号:bugstack虫洞栈 {获取学习源码} * 虫洞群:①群5398358 ②群5360692 * Create by fuzhengwei on @2019 */@Configurationpublic class PublisherConfig { @Bean public RedisTemplate<String, Object> redisMessageTemplate(RedisConnectionFactory connectionFactory) { RedisTemplate<String, Object> template = new RedisTemplate<>(); template.setConnectionFactory(connectionFactory); template.setDefaultSerializer(new FastJsonRedisSerializer<>(Object.class)); return template; }}
>redis/config/ReceiverConfig.java | redis消息的订阅者,集成与SpringBoot的配置方式。可以订阅多个主题,本章节只订阅一个。
/** * 订阅者 * 虫洞栈:https://bugstack.cn * 公众号:bugstack虫洞栈 {获取学习源码} * 虫洞群:①群5398358 ②群5360692 * Create by fuzhengwei on @2019 */@Configurationpublic class ReceiverConfig { @Bean public RedisMessageListenerContainer container(RedisConnectionFactory connectionFactory, MessageListenerAdapter msgAgreementListenerAdapter) { RedisMessageListenerContainer container = new RedisMessageListenerContainer(); container.setConnectionFactory(connectionFactory); container.addMessageListener(msgAgreementListenerAdapter, new PatternTopic("itstack-demo-netty-push-msgAgreement")); return container; } @Bean public MessageListenerAdapter msgAgreementListenerAdapter(MsgAgreementReceiver receiver) { return new MessageListenerAdapter(receiver, "receiveMessage"); }}
>redis/MsgAgreementReceiver.java | 实现抽象类用于接收订阅到的消息,接收消息后进行业务处理
/** * 虫洞栈:https://bugstack.cn * 公众号:bugstack虫洞栈 {获取学习源码} * 虫洞群:①群5398358 ②群5360692 * Create by fuzhengwei on @2019 */@Servicepublic class MsgAgreementReceiver extends AbstractReceiver { private Logger logger = LoggerFactory.getLogger(MsgAgreementReceiver.class); @Override public void receiveMessage(Object message) { logger.info("接收到PUSH消息:{}", message); MsgAgreement msgAgreement = JSON.parseObject(message.toString(), MsgAgreement.class); String toChannelId = msgAgreement.getToChannelId(); Channel channel = CacheUtil.cacheChannel.get(toChannelId); if (null == channel) return; channel.writeAndFlush(MsgUtil.obj2Json(msgAgreement)); }}
>redis/RedisUtil.java | redis操作工具类,帮助存储数据。以下是将链接到服务的用户信息存放到redis方便可以在每个服务端都能看到这份用户链接数据。
/** * 虫洞栈:https://bugstack.cn * 公众号:bugstack虫洞栈 {关注获取学习源码} * Create by fuzhengwei on 2019 */@Service("redisUtil")public class RedisUtil { @Autowired private StringRedisTemplate redisTemplate; public void pushObj(UserChannelInfo userChannelInfo) { redisTemplate.opsForHash().put("itstack-demo-netty-2-09-user", userChannelInfo.getChannelId(), JSON.toJSONString(userChannelInfo)); } public List<UserChannelInfo> popList() { List<Object> values = redisTemplate.opsForHash().values("itstack-demo-netty-2-09-user"); if (null == values) return new ArrayList<>(); List<UserChannelInfo> userChannelInfoList = new ArrayList<>(); for (Object strJson : values) { userChannelInfoList.add(JSON.parseObject(strJson.toString(), UserChannelInfo.class)); } return userChannelInfoList; } public void remove(String channelId) { redisTemplate.opsForHash().delete("itstack-demo-netty-2-09-user",channelId); } public void clear(){ redisTemplate.delete("itstack-demo-netty-2-09-user"); }}
>server/MyServerHandler.java | 处理接收到的信息,尤其在channelRead中,将接受者不是本服务端的用户,进行全局push
/** * 虫洞栈:https://bugstack.cn * 公众号:bugstack虫洞栈 {关注获取学习源码} * Create by fuzhengwei on 2019 */public class MyServerHandler extends ChannelInboundHandlerAdapter { private Logger logger = LoggerFactory.getLogger(MyServerHandler.class); private ExtServerService extServerService; public MyServerHandler(ExtServerService extServerService) { this.extServerService = extServerService; } /** * 当客户端主动链接服务端的链接后,这个通道就是活跃的了。也就是客户端与服务端建立了通信通道并且可以传输数据 */ @Override public void channelActive(ChannelHandlerContext ctx) throws Exception { SocketChannel channel = (SocketChannel) ctx.channel(); System.out.println("链接报告开始"); System.out.println("链接报告信息:有一客户端链接到本服务端。channelId:" + channel.id()); System.out.println("链接报告IP:" + channel.localAddress().getHostString()); System.out.println("链接报告Port:" + channel.localAddress().getPort()); System.out.println("链接报告完毕"); //保存用户信息 UserChannelInfo userChannelInfo = new UserChannelInfo(channel.localAddress().getHostString(), channel.localAddress().getPort(), channel.id().toString(), new Date()); extServerService.getRedisUtil().pushObj(userChannelInfo); CacheUtil.cacheChannel.put(channel.id().toString(), channel); //通知客户端链接建立成功 String str = "通知客户端链接建立成功" + " " + new Date() + " " + channel.localAddress().getHostString() + "\r\n"; ctx.writeAndFlush(MsgUtil.buildMsg(channel.id().toString(), str)); } /** * 当客户端主动断开服务端的链接后,这个通道就是不活跃的。也就是说客户端与服务端的关闭了通信通道并且不可以传输数据 */ @Override public void channelInactive(ChannelHandlerContext ctx) throws Exception { System.out.println("客户端断开链接" + ctx.channel().localAddress().toString()); extServerService.getRedisUtil().remove(ctx.channel().id().toString()); CacheUtil.cacheChannel.remove(ctx.channel().id().toString(), ctx.channel()); } @Override public void channelRead(ChannelHandlerContext ctx, Object objMsgJsonStr) throws Exception { //接收msg消息{与上一章节相比,此处已经不需要自己进行解码} System.out.println(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(new Date()) + " 接收到消息内容:" + objMsgJsonStr); MsgAgreement msgAgreement = MsgUtil.json2Obj(objMsgJsonStr.toString()); String toChannelId = msgAgreement.getToChannelId(); //判断接收消息用户是否在本服务端 Channel channel = CacheUtil.cacheChannel.get(toChannelId); if (null != channel) { channel.writeAndFlush(MsgUtil.obj2Json(msgAgreement)); return; } //如果为NULL则接收消息的用户不在本服务端,需要push消息给全局 logger.info("接收消息的用户不在本服务端,PUSH!"); extServerService.push(msgAgreement); } /** * 抓住异常,当发生异常的时候,可以做一些相应的处理,比如打印日志、关闭链接 */ @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { ctx.close(); extServerService.getRedisUtil().remove(ctx.channel().id().toString()); CacheUtil.cacheChannel.remove(ctx.channel().id().toString(), ctx.channel()); System.out.println("异常信息:\r\n" + cause.getMessage()); }}
>util/CacheUtil.java | 缓存必要信息,用于业务流程处理
/** * 虫洞栈:https://bugstack.cn * 公众号:bugstack虫洞栈 {关注获取学习源码} * 虫洞群:①群5398358 ②群5360692 * Create by fuzhengwei on 2019 */public class CacheUtil { // 缓存channel public static Map<String, Channel> cacheChannel = Collections.synchronizedMap(new HashMap<String, Channel>()); // 缓存服务信息 public static Map<Integer, ServerInfo> serverInfoMap = Collections.synchronizedMap(new HashMap<Integer, ServerInfo>()); // 缓存服务端 public static Map<Integer, NettyServer> serverMap = Collections.synchronizedMap(new HashMap<Integer, NettyServer>());}
>web/NettyController.java | 接口处理控制类,方便我们操作服务端方法,包括启动Netty服务、获取用户信息等
/** * 虫洞栈:https://bugstack.cn * 公众号:bugstack虫洞栈 {获取学习源码} * 虫洞群:①群5398358 ②群5360692 * Create by fuzhengwei on @2019 */@Controllerpublic class NettyController { private Logger logger = LoggerFactory.getLogger(NettyController.class); //默认线程池 private static ExecutorService executorService = Executors.newFixedThreadPool(2); @Value("${server.port}") private int serverPort; @Autowired private ExtServerService extServerService; @Resource private RedisUtil redisUtil; //Netty服务端 private NettyServer nettyServer; @RequestMapping("/index") public String index(Model model) { model.addAttribute("serverPort", serverPort); return "index"; } @RequestMapping("/openNettyServer") @ResponseBody public EasyResult openNettyServer() { try { int port = NetUtil.getPort(); logger.info("启动Netty服务,获取可用端口:{}", port); nettyServer = new NettyServer(new InetSocketAddress(port), extServerService); Future<Channel> future = executorService.submit(nettyServer); Channel channel = future.get(); if (null == channel) { throw new RuntimeException("netty server open error channel is null"); } while (!channel.isActive()) { logger.info("启动Netty服务,循环等待启动..."); Thread.sleep(500); } CacheUtil.serverInfoMap.put(port, new ServerInfo(NetUtil.getHost(), port, new Date())); CacheUtil.serverMap.put(port, nettyServer); logger.info("启动Netty服务,完成:{}", channel.localAddress()); return EasyResult.buildSuccessResult(); } catch (Exception e) { logger.error("启动Netty服务失败", e); return EasyResult.buildErrResult(e); } } @RequestMapping("/closeNettyServer") @ResponseBody public EasyResult closeNettyServer(int port) { try { logger.info("关闭Netty服务开始,端口:{}", port); NettyServer nettyServer = CacheUtil.serverMap.get(port); if (null == nettyServer) { CacheUtil.serverMap.remove(port); return EasyResult.buildSuccessResult(); } nettyServer.destroy(); CacheUtil.serverMap.remove(port); CacheUtil.serverInfoMap.remove(port); logger.info("关闭Netty服务完成,端口:{}", port); return EasyResult.buildSuccessResult(); } catch (Exception e) { logger.error("关闭Netty服务失败,端口:{}", port, e); return EasyResult.buildErrResult(e); } } @RequestMapping("/queryNettyServerList") @ResponseBody public Collection<ServerInfo> queryNettyServerList() { try { Collection<ServerInfo> serverInfos = CacheUtil.serverInfoMap.values(); logger.info("查询服务端列表。{}", JSON.toJSONString(serverInfos)); return serverInfos; } catch (Exception e) { logger.info("查询服务端列表失败。", e); return null; } } @RequestMapping("/queryUserChannelInfoList") @ResponseBody public List<UserChannelInfo> queryUserChannelInfoList() { try { logger.info("查询用户列表信息开始"); List<UserChannelInfo> userChannelInfoList = redisUtil.popList(); logger.info("查询用户列表信息完成。list:{}", JSON.toJSONString(userChannelInfoList)); return userChannelInfoList; } catch (Exception e) { logger.error("查询用户列表信息失败", e); return null; } }}
>resources/application.yml | 基础配置,在我们启动服务端的时候,如果只有一台机器模拟,那么需要改变server.port端口{8080、8081}
server: port: 8080spring: mvc: view: prefix: /WEB-INF/ suffix: .jsp redis: host: 127.0.0.1 port: 6379
>index.jap | 页面操作,控制和展示的一些内容
<%-- 虫洞栈:https://bugstack.cn 公众号:bugstack虫洞栈 {获取学习源码} Create by fuzhengwei on 2019--%><%@ page contentType="text/html;charset=UTF-8" language="java" %><title>关注公众号:bugstack虫洞栈 | 专题案例开发,关注取源码 | bugstack.cn 付政委</title><meta charset="UTF-8"><link rel="stylesheet" type="text/css" href="res/js/themes/default/easyui.css"><link rel="stylesheet" type="text/css" href="res/js/themes/icon.css"><script type="text/javascript" src="res/js/jquery.min.js"></script><script type="text/javascript" src="res/js/jquery.easyui.min.js"></script><style></style><script>util = { formatDate: function (value, row, index) { if (null == value) return ""; var date = new Date(); date.setTime(value); return date.format('yyyy-MM-dd HH:mm:ss'); }};</script></head><body> <div style="margin:20px 0;"></div> <table class="easyui-datagrid" title="localhost:${serverPort} | Netty服务端" style="width:700px;height:250px" data-options="rownumbers:true,singleSelect:true,url:'/queryNettyServerList',method:'get',toolbar:toolbar"> <thead> <tr> <th data-options="field:'ip'">IP</th> <th data-options="field:'port'">端口</th> <th data-options="field:'openDate'">启动时间</th> </tr> </thead> </table> <script type="text/javascript"> var toolbar = [{ text:'启动', iconCls:'icon-open', handler:function(){ $.post('/openNettyServer',{}, function (res) { if (res.success) { $.messager.show({ title: '消息提示', msg: '启动成功,请稍后刷新页面!' }); $('#easyui-datagrid').datagrid('reload'); } else { $.messager.show({ title: 'Error', msg: res.msg }); } }, 'json'); } },'-',{ text:'关闭', iconCls:'icon-close', handler:function(){ //可以自己添加实现 } }]; </script> <hr/> <!-- server-user --> <table class="easyui-datagrid" title="localhost:${serverPort} | 用户链接信息" style="width:700px;height:250px" data-options="rownumbers:true,singleSelect:true,url:'/queryUserChannelInfoList',method:'get'"> <thead> <tr> <th data-options="field:'ip'">IP</th> <th data-options="field:'port'">端口</th> <th data-options="field:'channelId'">用户ID</th> <th data-options="field:'linkDate'">链接时间</th> </tr> </thead> </table></body></html>
测试结果
>启动Redis服务 | 案例中使用windwos版本
>启动2次SpringBoot,模拟Netty集群[不同端口8080、8081] | Plugins/spring-boot/run 双击启动
2019-09-01 12:59:29.649 INFO 8952 --- [nio-8081-exec-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring FrameworkServlet 'dispatcherServlet'2019-09-01 12:59:29.649 INFO 8952 --- [nio-8081-exec-1] o.s.web.servlet.DispatcherServlet : FrameworkServlet 'dispatcherServlet': initialization started2019-09-01 12:59:29.681 INFO 8952 --- [nio-8081-exec-1] o.s.web.servlet.DispatcherServlet : FrameworkServlet 'dispatcherServlet': initialization completed in 32 ms2019-09-01 12:59:31.350 INFO 8952 --- [nio-8081-exec-2] o.i.demo.netty.web.NettyController : 查询服务端列表。[]2019-09-01 12:59:31.371 INFO 8952 --- [nio-8081-exec-3] o.i.demo.netty.web.NettyController : 查询用户列表信息开始2019-09-01 12:59:31.380 INFO 8952 --- [nio-8081-exec-3] o.i.demo.netty.web.NettyController : 查询用户列表信息完成。list:[]2019-09-01 13:04:22.864 INFO 8952 --- [nio-8081-exec-6] o.i.demo.netty.web.NettyController : 启动Netty服务,获取可用端口:73982019-09-01 13:04:22.879 INFO 8952 --- [pool-1-thread-1] o.itstack.demo.netty.server.NettyServer : itstack-demo-netty server start done. {关注公众号:bugstack虫洞栈,获取源码}2019-09-01 13:04:22.880 INFO 8952 --- [nio-8081-exec-6] o.i.demo.netty.web.NettyController : 启动Netty服务,完成:/0:0:0:0:0:0:0:0:73982019-09-01 13:04:23.612 INFO 8952 --- [nio-8081-exec-9] o.i.demo.netty.web.NettyController : 查询服务端列表。[{"ip":"10.13.28.13","openDate":1567314262880,"port":7398}]2019-09-01 13:04:23.634 INFO 8952 --- [io-8081-exec-10] o.i.demo.netty.web.NettyController : 查询用户列表信息开始2019-09-01 13:04:23.636 INFO 8952 --- [io-8081-exec-10] o.i.demo.netty.web.NettyController : 查询用户列表信息完成。list:[]链接报告开始链接报告信息:有一客户端链接到本服务端。channelId:3a2d5cee链接报告IP:10.13.28.13链接报告Port:7398链接报告完毕2019-09-01 13:04:42.704 INFO 8952 --- [nio-8081-exec-2] o.i.demo.netty.web.NettyController : 查询服务端列表。[{"ip":"10.13.28.13","openDate":1567314262880,"port":7398}]2019-09-01 13:04:42.738 INFO 8952 --- [nio-8081-exec-3] o.i.demo.netty.web.NettyController : 查询用户列表信息开始2019-09-01 13:04:42.755 INFO 8952 --- [nio-8081-exec-3] o.i.demo.netty.web.NettyController : 查询用户列表信息完成。list:[{"channelId":"39d45ff7","ip":"10.13.28.13","linkDate":1567314278944,"port":7397},{"channelId":"3a2d5cee","ip":"10.13.28.13","linkDate":1567314280442,"port":7398}]2019-09-01 13:05:25.545 INFO 8952 --- [ container-2] o.i.d.netty.redis.MsgAgreementReceiver : 接收到PUSH消息:{"content":"hi! I'm 微信公众号:bugstack虫洞栈 | 欢迎关注&获取源码。* 来自A服务端里用户向B服务端里用户发送信息。[结尾换行,用于处理半包粘包]","toChannelId":"3a2d5cee"}2019-09-01 13:05:26.107 INFO 8952 --- [ container-3] o.i.d.netty.redis.MsgAgreementReceiver : 接收到PUSH消息:{"content":"hi! I'm 微信公众号:bugstack虫洞栈 | 欢迎关注&获取源码。* 来自A服务端里用户向B服务端里用户发送信息。[结尾换行,用于处理半包粘包]","toChannelId":"3a2d5cee"}2019-09-01 13:05:27.025 INFO 8952 --- [ container-4] o.i.d.netty.redis.MsgAgreementReceiver : 接收到PUSH消息:{"content":"hi! I'm 微信公众号:bugstack虫洞栈 | 欢迎关注&获取源码。* 来自A服务端里用户向B服务端里用户发送信息。[结尾换行,用于处理半包粘包]","toChannelId":"3a2d5cee"}2019-09-01 13:05:27.545 INFO 8952 --- [ container-5] o.i.d.netty.redis.MsgAgreementReceiver : 接收到PUSH消息:{"content":"hi! I'm 微信公众号:bugstack虫洞栈 | 欢迎关注&获取源码。* 来自A服务端里用户向B服务端里用户发送信息。[结尾换行,用于处理半包粘包]","toChannelId":"3a2d5cee"}2019-09-01 13:05:28.559 INFO 8952 --- [ container-6] o.i.d.netty.redis.MsgAgreementReceiver : 接收到PUSH消息:{"content":"hi! I'm 微信公众号:bugstack虫洞栈 | 欢迎关注&获取源码。* 来自A服务端里用户向B服务端里用户发送信息。[结尾换行,用于处理半包粘包]","toChannelId":"3a2d5cee"}
>启动2个以上的NetAssist分别链接到不同的服务端,以模拟测试跨服务通信,最后在客户端发送消息传递给另外一个不在本服务端的客户端。
{"content":"hi! I'm 微信公众号:bugstack虫洞栈 | 欢迎关注&获取源码。* 来自A服务端里用户向B服务端里用户发送信息。[结尾换行,用于处理半包粘包]","toChannelId":"3a2d5cee"}
>最终运行效果
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