node自学之路(2) node实现DNS查询 

/**
 * Created by iwang on 2017/2/16.
 */
var http = require('http'), //服务器创建
    dns = require('dns'),   //DNS查询
    fs = require('fs'),     //文件操作
    url = require('url'),   //url操作
    querystring = require('querystring');   //字符串处理
http.createServer(function (req,res) {
    req.setEncoding('utf8');
   res.writeHead(200,{'Content-Type':'text/html'});
    // var readPath = __dirname+'/'+url.parse('index.html').pathname;
    var pathname = url.parse(req.url).pathname;

    // var indexPage = fs.readFileSync(readPath);
    router(res,req,pathname)
}).listen(3000,'127.0.0.1');
console.log('server begin');
function router(res,req,pathname) {
    switch (pathname){
        case "/parse":
            parseDns(res,req)
        break;
        default:
            goIndex(res,req)
    }
}
function goIndex(res,req) {
    console.log()
    var readPath = __dirname + '\\' + url.parse('index.html').pathname;
    var indexPage = fs.readFileSync('index.html');
    console.log(indexPage)
    res.end(indexPage)
}
function parseDns(res,req) {
    var poseData = "";
    req.addListener('data',function (poseDataChunk) {
        poseData += poseDataChunk;
    });
    req.addListener('end',function () {
       var retData = getDns(poseData,function (domain,addresses) {
           res.writeHead(200,{'Content-Type':'text/html'});
           res.end('<!DOCTYPE html>\
               <html lang="en">\
               <head>\
               <meta charset="UTF-8">\
               <title>DNS查询</title>\
               <meta http-equiv="content-type" content="text/html;charset=utf-8">\
               </head>\
               <body>\
               <div style="text-align: center;">\
               Domain:<span style="color:red">'+domain+'</span>\
               IP:<span style="color:red">'+addresses.join(',')+'</span>\
               </div>\
               </body>\
               </html>')
       });
        return;
    })
}
function getDns(posedata,callback) {
    var domain = querystring.parse(posedata).search_dns;
    dns.resolve(domain,function (err, addresses) {
        if(!addresses){
            addresses = ['不存在域名']
        }
        callback(domain,addresses)
    })
}

输入www.baidu.com域名测试：

结果：

posted @ 2017-02-16 22:27  iwang5566  阅读(292)  评论(0)  编辑  收藏  举报