nodejs是服务器端js脚本语言, express是nodejs的web框架,通过实现系统监控功能进一步学习nodejs.
主要由四个程序文件实现:server.js启动web服务;routing.js路由解析跳转到功能实现的文件和方法;sysinfo.js实现取当前系统的各项信息指标;sysinfo.html 请求及显示系统信息。
结果如下图:
server.js
/** * User: jacky * Date: 11-3-30 * Time: 上午11:11 * To change this template use File | Settings | File Templates. */ var express = require('express'); var app = express.createServer(); var path = require('path'); var fs = require('fs'); var url = require('url'); //configration //每次启动都会执行的配置 app.configure(function(){ //console.log('in configure'); app.use(express.methodOverride()); app.use(express.bodyParser()); app.use(app.router); app.use(express.logger({ format: ':method :uri' })); }); //默认方式 $ node ./server.js 为开发模式 app.configure('development', function(){ //console.log('in configure with development'); app.use(express.static(__dirname + '/static')); //console.log(__dirname + '/static'); app.use(express.errorHandler({ dumpExceptions: true, showStack: true })); }); //以 $NODE_ENV=production node ./server.js 方式运行,即为生产模式 app.configure('production', function(){ //console.log('in configure with production'); var oneYear = 31557600000; app.use(express.static(__dirname + '/static', { maxAge: oneYear })); app.use(express.errorHandler()); }); // routing settings //重定向静态文件 html,css,js,jpg,png => /static/+req.url app.all('/*.(html|css|js|jpg|png){1}', function(req, res, next){ //var static_file_formats = ['.html','.css','.js','.jpg','.png']; //console.log(path.extname(req.url)); var realpath = __dirname + '/static' + url.parse(req.url).pathname; //console.log(realpath); if(path.existsSync(realpath)){ res.end(fs.readFileSync(realpath)); }else{ res.end('Cannot find request url: '+req.url); } }); //加载配置文件routing.js到变量routings. [/scripts/routing.js] var routings = require(__dirname + '/scripts/routing.js').routings; for(var r in routings){ var pf = require(__dirname + routings[r].file)[routings[r].processFunction]; if(routings[r].method == 'get') app.get(r, pf,function(req, res){}); else if(routings[r].method == 'post') app.post(r,pf); else app.all(r, pf,function(req, res){}); } app.listen(8080); console.log('Server running at http://127.0.0.1:8080/');
routing.js
// the method:[get|post|all], default is all exports.routings = { '/getSysInfo':{method:'get', file:'/scripts/sysinfo.js', processFunction:'get'}, };
sysinfo.js
var os = require('os'); //过虑掉字符串首尾格式,替换字符串中的多个空格为一个空格 function trim(s){ return s.replace(/(^\s*)|(\s*$)/g, '').replace(/\s+/g,' '); } exports.get = function (req, res, next) { //df --total |grep total var sysinfo = {'hostname' : os.hostname(), 'systemtype' : os.type(), 'release' : os.release(), 'uptime' : os.uptime(), 'loadavg' : os.loadavg(), 'totalmem' : os.totalmem(), 'freemem' : os.freemem(), 'cpus' : os.cpus(), 'disk' : '' }; var exec = require('child_process').exec; exec('df --total |grep total', function (error, stdout, stderr) { if (error !== null) { console.log('exec error: ' + error); }else{ var tmp = trim(stdout).split(' '); sysinfo.disk = {total:tmp[1],used:tmp[2],free:tmp[3]}; } res.send(JSON.stringify(sysinfo)); }); };
sysinfo.html
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/> <title>系统监控</title> <style type="text/css"> table{ width:600px; border-collapse:collapse; border:solid #999; border-width:1px 1px 1px 1px; color:#4682B4; } table th,table td {border:solid #999;border-width:0 1px 1px 0;padding:2px;} table td {text-align:center;} span {color:#8B8989} .tablecontent {color:#8B8989} </style> </head> <script type="text/javascript" src="http://www.google.com/jsapi"></script> <script type="text/javascript"> google.load('jquery', '1.5.1'); google.load('visualization', '1', {'packages':['piechart']}); //google.setOnLoadCallback(drawChart); function drawDiskChart(used,free) { var data = new google.visualization.DataTable(); data.addColumn('string', 'Space'); data.addColumn('number', 'Space number'); data.addRows([ ['未使用'+formatK2GB(free), free], ['已使用'+formatK2GB(used), used] ]); var chart = new google.visualization.PieChart(document.getElementById('disk_chart_div')); chart.draw(data, {width: 400, height: 240, is3D: true, title: '磁盘使用情况'}); } function drawMemChart(used,free) { var data = new google.visualization.DataTable(); data.addColumn('string', 'Space'); data.addColumn('number', 'Space number'); data.addRows([ ['空闲'+formatB2MB(free), free], ['已使用'+formatB2MB(used), used] ]); var chart = new google.visualization.PieChart(document.getElementById('mem_chart_div')); chart.draw(data, {width: 400, height: 240, is3D: true, title: '内存使用情况'}); } </script> <!--<script type="text/javascript" src="/js/jquery-1.5.1.min.js"></script>--> <script type="text/javascript"> //过虑掉字符串首尾格式,替换字符串中的多个空格为一个空格。 function trim(s){ return s.replace(/(^\s*)|(\s*$)/g, "").replace(/\s+/g,' '); } //转换从字节到兆字节 function formatB2MB(num){ return parseInt(num/(1000*1000))+' MB'; } //转换从K字节到G字节 function formatK2GB(num){ return parseInt(num/(1000*1000))+' GB'; } $(document).ready(function(){ //alert($.fn.jquery); //显示jquery版本号 loadSysInfo(); setInterval(loadSysInfo,5000); }); function loadSysInfo(){ $.ajax({url:"/getSysInfo", success:function(data){ //alert(data.systemtype); $('#hostname').html(data.hostname); $('#systemtype').html(data.systemtype); $('#systemtype').html(data.systemtype); $('#release').html(data.release); $('#uptime').html(parseInt(data.uptime/(60*60))+' Hours'); $('#loadavg').html(data.loadavg.join(',')); $('#totalmem').html(formatB2MB(data.totalmem)); $('#freemem').html(formatB2MB(data.freemem)); $('#cpus').html(data.cpus.length); $('#disk').html(data.disk.used + ' used,' + data.disk.free +' free'); //填充cup表格 $('.tablecontent').remove(); for(var i in data.cpus){ $('<tr class=\'tablecontent\'><td>cpu'+ i +'</td>' + '<td>'+ data.cpus[i].model +'</td>' + '<td>'+ data.cpus[i].speed +'</td>' + '<td>'+ data.cpus[i].times.user +'</td>' + '<td>'+ data.cpus[i].times.nice +'</td>' + '<td>'+ data.cpus[i].times.sys +'</td>' + '<td>'+ data.cpus[i].times.idle +'</td>' + '<td>'+ data.cpus[i].times.irq +'</td>' + '</tr>').appendTo('#cputable'); } //图形显示 drawDiskChart(parseInt(data.disk.used),parseInt(data.disk.free)); drawMemChart(data.totalmem - data.freemem, data.freemem); }, cache:false, dataType:"json"}); } </script> <body> <strong>@sysinfo.html</strong><br><p> 主机名称:<span id='hostname'></span><br> 操作系统:<span id='systemtype'></span><br> 发行版本:<span id='release'></span><br> 运行时间:<span id='uptime'></span><br> 负载: <span id='loadavg'></span><br> 内存大小:<span id='totalmem'></span><br> 空闲内存:<span id='freemem'></span><br> CPUs: <span id='cpus'></span><br> 硬盘空间:<span id='disk'></span><br> <table id='cputable'> <tr><td colspan=8>CPU使用情况</td></tr> <tr><td>cpu</td> <td>model</td> <td>speed</td> <td>user</td> <td>nice</td> <td>sys</td> <td>idle</td> <td>irq</td> </tr> </table> <span id='disk_chart_div'></span> <span id='mem_chart_div'></span> </body> </html>