Node.js实现的BigPipe

来源：互联网发布：淘宝上好看的包包店铺编辑：程序博客网时间：2024/06/03 06:44

拿那篇文章中的php显示页做示例：

先输出页面的主体结构：

然后按顺序更新页面的内容：

2s后输出header

4s后输出content

6s后输出footer

从加载到显示共消耗约13s (2 + 4 + 6 + 1 ~= 13s)，符合预期结果

这个示例的源码（可复制至本地直接运行）：

/** * Created with JetBrains WebStorm. * User: Meteoric_cry * Date: 13-4-13 * Time: 上午11:10 * To change this template use File | Settings | File Templates. */var http = require('http');var server = http.createServer(function(req, res) {    res.writeHead(200, {       'Content-Type' : 'text/html',        'Transfer-Encoding' : 'chunked'    });    res.write([        '<!DOCTYPE html>',        '<html>',        '<head>',        '<meta charset="utf-8">',        '<title>Node.js Bigpipe Demo</title>',        '<style type="text/css">',        ' * {margin: 0; padding:0;}',        ' body {background-color:#fff;}',        ' div{border:2px solid #4F81BD; margin:30px; padding: 10px;}',        ' p {word-wrap:break-wrod; word-break:break-all; color: #666;}',        ' .red {color: #f00;}',        ' .blue {color:blue;}',        ' .green {color:green;}',        '</style>',        '<script>',        'var g_startTime = new Date();',        'var g_renderArr = []',        'function render(nodeID,html){',        '   g_renderArr.push(new Date())',        '    document.getElementById(nodeID).innerHTML=html;',        '}',        '</script>',        '</head>',        '<body>',        '<div id="header"><p>Loading...</p></div>',        '<div id="content"><p>Loading...</p></div>',        '<div id="footer"><p>Loading...</p></div>'    ].join('\r\n'));    function out_header() {        res.write("<script type='text/javascript'>render('header', '<p><span class=\"blue\">111111</span></p>');</script>\r\n");        setTimeout(out_content, 4 * 1000);    }    function out_content() {        res.write("<script type='text/javascript'>render('content', '<p><span class=\"red\">222222</span></p>');</script>\r\n");        setTimeout(out_footer, 6 * 1000);    }    function out_footer() {        res.write("<script type='text/javascript'>render('footer', '<p><span class=\"green\">333333</span></p>');</script>\r\n");        setTimeout(out_end, 1 * 1000);    }    function out_end() {        res.write([            '<script>',            'var str = [',            '    "start:" + g_startTime.toGMTString(),',            '    "header:" + g_renderArr[0].toGMTString() + "-" + (g_renderArr[0] - g_startTime) / 1000,',            '    "content:" + g_renderArr[1].toGMTString() + "-" + (g_renderArr[1] - g_renderArr[0]) / 1000,',            '    "footer:" + g_renderArr[2].toGMTString() + "-" + (g_renderArr[2] - g_renderArr[1]) / 1000,',            '    "end:" + new Date().toGMTString() + "-" + (new Date() - g_renderArr[2]) / 1000 + "-" + (new Date() - g_startTime) / 1000',            '].join("\\n");',            'alert(str);',            '</script>'        ].join(''));        res.end("\r\n</body></html>");    }    setTimeout(out_header, 2 * 1000);}).listen(3002);

上面是将界面的显示顺序固定写死了，下面将展示一个灵活的动态界面：

先输出6个内容容器，然后构建6个客户端请求，当收到请求数据时直接返回给客户端。如果你需要让界面的内容按顺序显示，只需要修改，返回的delay值，比如按索引值的大小进行修改

   1: var params = url.parse(request.url, true);

   2: var delay = params.query.id * 3000; console.log(delay);

这个示例的完整源码：

/** * Created with JetBrains WebStorm. * User: zhangyi * Date: 13-4-23 * Time: 上午10:57 * To change this template use File | Settings | File Templates. */var http = require('http');var sys = require('sys');var url = require("url");http.createServer(function(request, response) {    response.writeHead(200, {"Content-Type" : "text/html"});    response.write("<!Doctype html><html><head>");    response.write("<style type='text/css'>div{border:2px solid #4F81BD; margin:30px; padding: 10px;}</style>");    response.write("<script type=\"text/javascript\">function arrived(id,text) { var b=document.getElementById(id); b.innerHTML = text; }</script>");    response.write("</head><body><div>Progressive Loading");    for(var i = 0; i < 6; i++) {        response.write("<div id='" + i + "'>Loading...</div>");    }    response.write("</div>");    var down = 6;    for (i = 0; i < 6; i++) {        var proxy = http.createClient(2000, "localhost");        var proxyRequest = proxy.request("GET", "/?id=" + i, {"host" : "localhost"});        proxyRequest.addListener('response', function (proxyResponse) {            --down;            proxyResponse.addListener('data', function(chunk) {                response.write(chunk, 'binary');            });            proxyResponse.addListener('end', function() {                if(down == 0) {                    response.end();                }            });        });        proxyRequest.end();    }    response.write("</body></html>");}).listen(8080);http.createServer(function(request, response) {    var delay = Math.round(Math.random() * 8000);    /*    var params = url.parse(request.url, true);    var delay = params.query.id * 3000; console.log(delay);    */    setTimeout(function() {        var params = url.parse(request.url, true);        var id = params.query.id;        response.writeHead(200, {"Content-Type" : "text/html"});        var content = "<span>Content of Module " + id + "</span>";        response.write("<script>" +            "arrived('" + id + "', '" + content + "');" +            "</script>");        response.end();    }, delay);}).listen(2000);

上面的示例中并没有像第一个例子一样，显示输出header信息（'Transfer-Encoding' : 'chunked'），而浏览器，在response里却看到了，猜测是node.js在输出的时候内部加上去的。

相比php，node.js内部实现并没有“缓冲池”的功能，都是直接输出，很简单吧…

0 0