no 'end' callback for very large responses.

[rnewson]

Sufficiently large responses cause node.js some internal confusion that makes it never emit an 'end' event.

The following node.js code reproduces the problem. It appears to be chunked mode only, if you change 'res.writeHead(200, {"transfer-encoding":"chunked"});' to 'res.writeHead(200, {"content-length": len*chunk.length});' it exits successfully.

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

// Produce a very large response.
var chargen = http.createServer(function (req, res) {
    var chunk = '01234567890123456789';
    var len = req.headers['x-len'];
    res.writeHead(200, {"transfer-encoding":"chunked"});
    for (var i=0; i<len; i++) {
  res.write(chunk);
    }
    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) {
  res.writeHead(proxy_res.statusCode, proxy_res.headers);
  proxy_res.addListener('data', function(chunk) {
      res.write(chunk);
  });
  proxy_res.addListener('end', function() {
      res.close();
  });
    });
    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 ]);

[mikeal]

BTW, there is a test checked in https://github.com/ry/node/blob/master/test/disabled/test-http-big-proxy-responses.js

[ry]

fixed in f919216