request-resume.js

// Why does this code sample hang client
// connections if ASYNC === true?
//
// # Start server
// node test.js --sync port
// node test.js --async port
//
// # Test
// curl http://host:port/

var ASYNC = true;
var PORT = 8022;

var http = require('http');

var i = 2;

// --sync, --async flag
switch (process.argv[i]) {
case '--async':
    ASYNC = true;
    ++i;
    break;

case '--sync':
    ASYNC = false;
    ++i;
    break;

default:
    break;
}

// Port number
if (!isNaN(process.argv[i])) {
    PORT = Number(process.argv[i]);
    ++i;
}

http.createServer(function (req, res) {
    console.log("Request received");

    req.on('end', function () {
        console.log("'end' received");
    });

    req.pause();

    function respond() {
        req.on('end', function () {
            // This is not called if ASYNC === true
            console.log("'end' received (test passed)");
            res.writeHead(200);
            res.end();
        });

        req.resume();
    }

    if (ASYNC) {
        process.nextTick(respond);
    } else {
        respond();
    }
}).listen(PORT);

console.log(
    "%s-responding HTTP server listening on :%d",
    ASYNC ? "Asynchronously" : "Synchronously",
    PORT
);

To test:

curl http://localhost:8022/

curl should return almost instantaneously.