Test of a reverse HTTP request. Server will send data first, then wait for input from the client based on the data. Rude ugly code but it actually works.

client.js

var http = require('http');

var options = {
        hostname: '192.168.56.101',
        port: 1337,
        path: '/',
        method: 'POST'
};

var i = 0;

var req = http.request(options, function(res) {
        console.log('STATUS: ' + res.statusCode);
        console.log('HEADERS: ' + JSON.stringify(res.headers));
        res.setEncoding('utf8');
        res.on('data', function (chunk) {
                console.log('Received: "' + chunk + '"');

                // Parse reply
                var data = JSON.parse(chunk);
                var obj = {};
                Object.keys(data).forEach(function(key) {
                        if( (typeof data[key] === 'string') && (data[key][0] === '#') ) {
                                var id = parseInt( data[key].substr(10), 10);
                                obj[key] = function() {
                                        req.write('#call#' + id + ";\n");
                                };
                        } else {
                                obj[key] = data[key];
                        }
                });

                // Do things in 250 ms
                setTimeout(function() {
                        obj.inc();
                }, 0.250*1000);

        });
        res.on('end', function() {
                console.log("END of Response");
        });
});

req.on('error', function(e) {
        console.error('ERROR: ' + e.message);
});

req.write('#start;'+"\n");

// End test in 2 seconds
setTimeout(function() {
        req.end();
}, 2*1000);

httpd.js

var data = {
        'count':10,
        'inc': function() { return this.count++; },
        'dec': function() { return this.count--; }
};

var http = require('http');
http.createServer(function (req, res) {
        req.pause();
        console.log('Started new request');

        req.setEncoding('utf8');
                                                                                                                                                                              
        var obj = {}, funs = [];
        Object.keys(data).map(function(key) {
                if(typeof data[key] === 'function') {
                        funs.push(data[key].bind(data));
                        obj[key] = '#function[' + (funs.length-1) + ']';
                } else {
                        obj[key] = data[key];
                }
        });
        res.writeHead(200, {'Content-Type': 'text/plain'});
        res.write(JSON.stringify(obj) + "\n");

        req.on('data', function(chunk) {
                console.log("Received: '"+ chunk + "'");
                var found = chunk.match(/#call#([0-9]+);/);
                if(found) {
                        var id = parseInt(found[1], 10);
                        console.log("Parsed #" + id + ", calling it next...");
                        if(funs[id]) {
                                funs[id]();
                        } else {
                                console.error("No such function!");
                        }
                }
        });

        req.on('end', function() {
                console.log("Received end event");
                res.end();
        });

        req.resume();
}).listen(1337, '192.168.56.101');
console.log('Server running at http://192.168.56.101:1337/');