两种http代理方式的实现

proxy.js

/**
 * @fileoverview simple project assets proxy
 * @author 张挺 <[email protected]>
 */
var fs = require('fs'),
    path = require('path'),
    http = require('http'),
    https = require('https'),
    url = require('url'),
    httpProxy = require('http-proxy');

var proxy = new httpProxy.RoutingProxy();

http.createServer(function (req, res) {
    var urlObj = url.parse(req.url, true),
        domain = req.headers['x-forwarded-host'] 
            || req.headers['X-Forwarded-For']
        	|| urlObj.query.domain,
        port = urlObj.query.port;

    if(domain) {
        req.headers["host"] = domain;

        proxy.proxyRequest(req, res, {
            host: domain,
            port: port ? port : 80
        });
    } else {
        res.statusCode = 404;
        res.end();
    }
    
}).listen(3000);

proxy2.js

/**
 * @fileoverview simple project assets proxy
 * @author 张挺 <[email protected]>
 */
var fs = require('fs'),
    path = require('path'),
    http = require('http'),
    https = require('https'),
    url = require('url'),
    request = require('request');

http.createServer(function (req, res) {
  var urlObj = url.parse(req.url, true),
    	domain = req.headers['x-forwarded-host'] 
            || req.headers['X-Forwarded-For']
            || urlObj.query.domain,
    	port = urlObj.query.port,
    	newUrlObj = {};

	delete urlObj.query['domain'];
	delete urlObj.query['port'];
    
    newUrlObj.protocol = 'http';
	newUrlObj.hostname = domain;
	newUrlObj.query = urlObj.query;
	newUrlObj.auth = urlObj.auth;
	newUrlObj.hash = urlObj.hash;
	newUrlObj.pathname = urlObj.pathname;
	if(port) {
		newUrlObj.port = port;
	}

    if(domain) {
		request(url.format(newUrlObj), {
			headers: {
	            "User-Agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.110 Safari/537.36"
	        }
		}, function (error, response, body) {
			if (!error && response.statusCode == 200) {
				res.end(body);
			} else {
				res.statusCode = 404;
        		res.end();
			}
		})
    } else {
        res.statusCode = 404;
        res.end();
    }
}).listen(3000);

针对最新版本的node和http-proxy进行更新

/**
 * @fileoverview simple project assets proxy
 * @author 张挺 <[email protected]>
 * @support node 0.11
 */
var fs = require('fs'),
    path = require('path'),
    http = require('http'),
    https = require('https'),
    url = require('url'),
    httpProxy = require('http-proxy');

var proxy = httpProxy.createProxyServer({});

http.createServer(function (req, res) {
    if(req.url == '/') {
      res.end('ok');
      return;
    }

    var urlObj = url.parse(req.url, true);

    //fix in node 0.11
    urlObj.query = urlObj.query || {};

    var domain = req.headers['x-forwarded-host'] 
            || req.headers['X-Forwarded-For']
          || urlObj.query.domain,
        port = urlObj.query.port;

    if(domain) {
        req.headers["host"] = domain;

        proxy.web(req, res, { target: 'http://' + domain + ':' + (port ? port : 80) });

    } else {
        res.statusCode = 404;
        res.end();
    }

}).listen(3000);