gistfile1.js

var sys = require("sys"),
fs = require("fs"),
http = require("http"),
url = require("url");

var base_chunk = '01234567890123456789';

// Produce a very large response.
var chargen = http.createServer(function (req, res) {
    var len = req.headers['x-len'];
    res.writeHead(200, {"transfer-encoding":"chunked"});
    for (var i=0; i<len; i++) {
	res.write(base_chunk+"-"+i);
    }
    sys.puts("chargen: sent "+len+" chunks back");
    res.close();
});
chargen.listen(9000);

// Proxy to the chargen server.
var proxy = http.createServer(function (req, res) {
    var proxy_req = http.createClient(9000, 'localhost')
	.request(req.method, req.url, req.headers);
    proxy_req.addListener('response', function(proxy_res) {
        var counter = 0;
        var got_mismatch = false;
	res.writeHead(proxy_res.statusCode, proxy_res.headers);
	proxy_res.addListener('data', function(chunk) {
            var expected=base_chunk+"-"+counter;
            if (!got_mismatch && chunk !== expected) {
               got_mismatch = true;
               sys.puts("proxy: expected:"+expected+" got:"+chunk);
	    }
	    res.write(chunk);
	    counter++;
	});
	proxy_res.addListener('end', function() {
	    res.close();
            sys.puts("proxy: total chunks "+counter);
	});
    });
    proxy_req.close();
});
proxy.listen(9001);

function call_chargen(list) {
  if (list.length > 0) {
    sys.debug("calling chargen for " + list[0] + " chunks.");
    var req = http.createClient(9001, 'localhost').request('/', {'x-len': list[0]});
    req.addListener('response', function(res) {
      res.addListener('end', function() {
        sys.debug("end for " + list[0] + " chunks.");
        list.shift();
        call_chargen(list);
      });
    });
    req.close();
  }
  else {
    sys.puts("End of list.");
      proxy.close();
      chargen.close();
  }
}

call_chargen([ 100, 1000, 10000, 100000, 1000000 ]);

gistfile2.txt

DEBUG: calling chargen for 100 chunks.
chargen: sent 100 chunks back
proxy: total chunks 100
DEBUG: end for 100 chunks.
DEBUG: calling chargen for 1000 chunks.
chargen: sent 1000 chunks back
proxy: expected:01234567890123456789-274 got:012345678901
proxy: total chunks 1003
DEBUG: end for 1000 chunks.
DEBUG: calling chargen for 10000 chunks.
chargen: sent 10000 chunks back
proxy: expected:01234567890123456789-274 got:012345678901
proxy: total chunks 10029
DEBUG: end for 10000 chunks.
DEBUG: calling chargen for 100000 chunks.
chargen: sent 100000 chunks back
proxy: expected:01234567890123456789-274 got:012345678901