Combining cluster and node-http-proxy for part master and part worker http responses

nodejs-cluster-http-proxy.js

var cluster = require('cluster'),
    http = require('http'),
    httpProxy = require('http-proxy');

var httpPort = 4332;
var clusterSock = './cluster.sock';


var httpServer = http.createServer(function (req, res) {
        res.end('Worker! ' + process.pid);
});

var cl = cluster(httpServer)
        .set('workers', 5)
        .listen(clusterSock);

if (cl.isMaster) {
        var options = {
                target: { host: 'localhost', port: clusterSock }
        };

        httpProxy.createServer(options, function (req, res, proxy) {
                if (Date.now() % 10 < 5) {
                        console.log('Relaying to worker');

                        proxy.proxyRequest(req, res);
                } else {
                        console.log('Master response');

                        res.end('Master! ' + process.pid);
                }
        }).listen(httpPort);

        console.log('HTTP proxy listening on port', httpPort);
}