Uncaught exception triggered by response.end()

[veita]

With node 0.4.8 HTTP the attached HTTP server always produces the "TypeError: Cannot read property '_httpMessage' of null".

The server delivers HTML documents from its current working directory.

var
    g_sys  = require('sys'),
    g_http = require('http'),
    g_url  = require('url'),
    g_path = require('path'),
    g_fs   = require('fs'),

    log = console.log,

    staticFile = function(res, path, ct) {
        g_fs.stat(path, function(err, stats) {
            res.writeHead(200, 'OK', {'Content-Type': ct, 'Content-Length': stats.size});

            g_sys.pump(g_fs.createReadStream(path), res, function() {res.end();}); // error
            //g_sys.pump(g_fs.createReadStream(path), res); // no error
        });
    },

    main = function(req, res) {
        var
            url     = g_url.parse(req.url),
            strPath = g_path.join(process.cwd(), url.pathname);

        log("Path: " + strPath);

        staticFile(res, strPath, 'text/html');
    };


process.on('uncaughtException', function(err) {
    log('Uncaught exception:\n' + err);
});

process.on('SIGINT', function() {
    log('bye');
    process.exit(0);
});

g_http.createServer(main).listen(1337, '127.0.0.1');

[koichik]

util.pump() calls end() of writable stream.
https://github.com/joyent/node/blob/v0.4/lib/util.js#L391

I think end() was called twice in error case.

[veita]

You're right. My fault. end() is called twice, even if no error occurred.

But shouldn't the error message be more helpful? E.g. 'end() called for already closed object' or something like that. Another solution would be to let end() be idempotent, but I'm not sure if this is a better approach since it is prone to hide programming errors.