Nodejs实现多房间简易聊天室功能

1、前端界面代码

　　前端不是重点，够用就行，下面是前端界面，具体代码可到github下载。

2、服务器端搭建

　　本服务器需要提供两个功能：http服务和websocket服务，由于node的事件驱动机制，可将两种服务搭建在同一个端口下。

　　1、包描述文件：package.json,这里用到了两个依赖项，mime：确定静态文件mime类型，socket.io:搭建websocket服务，然后使用npm install  安装依赖

{
 "name": "chat_room",
 "version": "1.0.0",
 "description": "this is a room where you can chat with your friends",
 "main": "index.js",
 "scripts": {
  "test": "echo \"error: no test specified\" && exit 1"
 },
 "author": "sfs",
 "license": "isc",
 "dependencies": {
  "socket.io":"2.0.3",
  "mime":"1.3.6"
 }
}

　　2、http服务器

　　http服务主要是给web浏览器提供静态文件，既浏览器发来一个请求，服务器返回一个响应。

const 
  http=require('http'),
  fs=require('fs'),
  path=require('path'),
  mime=require('mime'),
  chatserver=require('./lib/chat_server');

var cache={};//缓存静态文件内容
//发送错误响应
function send404(response){
  response.writehead(404,{'content-type':'text/plain'});
  response.write('error 4.4:文件未找到。');
  response.end();
}
//发送文件内容
function sendfile(response,filepath,filecontents){
  response.writehead(
    200,
    {"content-type":mime.lookup(path.basename(filepath))}
  );
  response.end(filecontents);
}
//查找文件
function servestatic(response,cache,abspath){
  if(cache[abspath]){
    sendfile(response,abspath,cache[abspath]);
  }else{
    fs.exists(abspath,function(exists){
      if(exists){
        fs.readfile(abspath,function(err,data){
          if(err){
            send404(response);
          }else{
            cache[abspath]=data;
            sendfile(response,abspath,data);
          }
        });
      }else{
        send404(response);
      }
    });
  }
}
//入口
var server=http.createserver(function(request,response){
  var filepath=false;
  console.log(`new request for ${request.url}`);
  if(request.url==='/'){
    filepath='public/index.html';
  }else{
    filepath='public'+request.url;
  }

  var abspath='./'+filepath;
  servestatic(response,cache,abspath);
});
server.listen(3000,function(){
  console.log("the server is listening on prot 3000.");
});
chatserver.listen(server); //websocket服务也绑定到该端口上

　　3、socket服务

　　socket.io提供了开箱既用的虚拟通道，所以不需要任务手动转发消息到已连接的的用户，可以使用 socket.broadcast.to(room).emit('message','hello'); room为某个聊天室id

const 
  socketio=require('socket.io');
var io,
  guestnumber=1, //用户编号
  nicknames={},  //socket id对应的nickname
  namesused={},  //所有已使用的nickname
  allrooms={},  //聊天室--人数
  currentroom={}; //sockid--聊天室
module.exports.listen=function(server){
  io=socketio.listen(server);
  io.serveclient('log level',1);
  io.sockets.on('connection',function(socket){
    guestnumber=assignguestname(socket,guestnumber,nicknames);
    joinroom(socket,'lobby');
    handlemessagebroadcasting(socket,nicknames);
    handlenamechangeattempts(socket,nicknames,namesused);
    handleroomjoining(socket);
    socket.on('rooms',function(){
      socket.emit('rooms',json.stringify(allrooms));
    });
    handleclientdisconnection(socket,nicknames,namesused);
  });
};
//新socket连入，自动分配一个昵称
function assignguestname(socket,guesetnumber,nicknames){
  var name='guest'+guestnumber;
  nicknames[socket.id]=name;
  socket.emit('nameresult',{
    success:true,
    name:name
  });
  namesused[name]=1;
  return guestnumber+1;
}
//加入某个聊天室
function joinroom(socket,room){
  socket.join(room);
  var num=allrooms[room];
  if(num===undefined){
    allrooms[room]=1;
  }else{
    allrooms[room]=num+1;
  }
  currentroom[socket.id]=room;
  socket.emit('joinresult',{room:room});
  socket.broadcast.to(room).emit('message',{
    text:nicknames[socket.id]+' has join '+room+'.'
  });
  var usersinroom=io.sockets.adapter.rooms[room];
  if(usersinroom.length>1){
    var usersinroomsummary='users currently in '+room+' : ';
    for(var index in usersinroom.sockets){
      if(index!=socket.id){
        usersinroomsummary+=nicknames[index]+',';
      }
    }
    socket.emit('message',{text:usersinroomsummary}); 
  }
}
//修改昵称
function handlenamechangeattempts(socket,nicknames,namesused){
  socket.on('nameattempt',function(name){
    if(name.indexof('guest')==0){
      socket.emit('nameresult',{
        success:false,
        message:'names cannot begin with "guest".'
      });
    }else{
      if(namesused[name]==undefined){
        var previousname=nicknames[socket.id];
        delete namesused[previousname];
        namesused[name]=1;
        nicknames[socket.id]=name;
        socket.emit('nameresult',{
          success:true,
          name:name
        });
        socket.broadcast.to(currentroom[socket.id]).emit('message',{
          text:previousname+' is now known as '+name+'.'
        });
      }else{
        socket.emit('nameresult',{
          success:false,
          message:'that name is already in use.' 
        });
      }
    }
  });                                    
}
//将某个用户的消息广播到同聊天室下的其他用户
function handlemessagebroadcasting(socket){
  socket.on('message',function(message){
    console.log('message:---'+json.stringify(message));
    socket.broadcast.to(message.room).emit('message',{
      text:nicknames[socket.id]+ ': '+message.text
    });
  });
}
//加入/创建某个聊天室
function handleroomjoining(socket){
  socket.on('join',function(room){
    var temp=currentroom[socket.id];
    delete currentroom[socket.id];
    socket.leave(temp);
    var num=--allrooms[temp];
    if(num==0)
      delete allrooms[temp];
    joinroom(socket,room.newroom);
  });
}
//socket断线处理
function handleclientdisconnection(socket){
  socket.on('disconnect',function(){
    console.log("xxxx disconnect");
    allrooms[currentroom[socket.id]]--;
    delete namesused[nicknames[socket.id]];
    delete nicknames[socket.id];
    delete currentroom[socket.id];
  })
}

3、客户端实现socket.io

　　1、chat.js处理发送消息，变更房间，聊天命令。

var chat=function(socket){
  this.socket=socket;//绑定socket
}
//发送消息
chat.prototype.sendmessage=function(room,text){
  var message={
    room:room,
    text:text
  };
  this.socket.emit('message',message);
};
//变更房间
chat.prototype.changeroom=function(room){
  this.socket.emit('join',{
    newroom:room
  });
};
//处理聊天命令
chat.prototype.processcommand=function(command){
  var words=command.split(' ');
  var command=words[0].substring(1,words[0].length).tolowercase();
  var message=false;
  switch(command){
    case 'join':
      words.shift();
      var room=words.join(' ');
      this.changeroom(room);
      break;
    case 'nick':
      words.shift();
      var name=words.join(' ');
      this.socket.emit('nameattempt',name);
      break;
    default:
      message='unrecognized command.';
      break;
  }
  return message;
};

　　2、chat_ui.js 处理用户输入，根据输入调用chat.js的不同方法发送消息给服务器

function divescapedcontentelement(message){
  return $('<div></div>').text(message);
}
function divsystemcontentelement(message){
  return $('<div></div>').html('<i>'+message+'</i>');
}
function processuserinput(chatapp,socket){
  var message=$('#send-message').val();
  var systemmessage;
  if(message.charat(0)=='/'){
    systemmessage=chatapp.processcommand(message);
    if(systemmessage){
      $('#messages').append(divsystemcontentelement(systemmessage));
    }
  }else{
    chatapp.sendmessage($('#room').text(),message);
    $('#messages').append(divsystemcontentelement(message));
    $('#messages').scrolltop($('#messages').prop('scrollheight'));
  }
  $('#send-message').val('');
}

　　3、init.js客户端程序初始化   创建一个websocket连接，绑定事件。

if(window.websocket){
  console.log('this browser supports websocket');
}else{
  console.log('this browser does not supports websocket');
}
var socket=io.connect();
$(document).ready(function(){
  var chatapp=new chat(socket);
  socket.on('nameresult',function(result){
    var message;
    if(result.success){
      message='you are known as '+result.name+'.';
    }else{
      message=result.message;
    }
    console.log("nameresult:---"+message);
    $('#messages').append(divsystemcontentelement(message));
    $('#nickname').text(result.name);
  });
  socket.on('joinresult',function(result){
    console.log('joinresult:---'+result);
    $('#room').text(result.room);
    $('#messages').append(divsystemcontentelement('room changed.'));
  });
  socket.on('message',function(message){
    console.log('message:---'+message);
    var newelement=$('<div></div>').text(message.text);
    $('#messages').append(newelement);
    $('#messages').scrolltop($('#messages').prop('scrollheight'));
  });
  socket.on('rooms',function(rooms){
    console.log('rooms:---'+rooms);
    rooms=json.parse(rooms);
    $('#room-list').empty();
    for(var room in rooms){
      $('#room-list').append(divescapedcontentelement(room+':'+rooms[room]));
    }
    $('#room-list div').click(function(){
      chatapp.processcommand('/join '+$(this).text().split(':')[0]);
      $('#send-message').focus();
    });
  });
  setinterval(function(){
    socket.emit('rooms');
  },1000);
  $('#send-message').focus();
  $('#send-button').click(function(){
    processuserinput(chatapp,socket);
  });
});

完整代码，可到https://github.com/fleyx/chatroom 下载。

以上所述是小编给大家介绍的nodejs实现多房间简易聊天室功能，希望对大家有所帮助