Express 1: What's New, Release History & EOL Status

What Is New in Express 1

Why does Express 1 change the route handler signature?

The signature was simplified to (req, res, next) so that all route parameters are accessed uniformly via req.params.

Previously you wrote function(req, res, params, next), which forced a separate params argument. The change removes that redundancy and aligns Express with Connect's middleware pattern.

In practice you only need to update any custom middleware that still expects the old four-argument form. A quick grep for function (req, res, params will surface the places to fix.

Example before:

app.get('/user/:id', function (req, res, params, next) {
  var id = params.id;
  // ...
});

After upgrade:

app.get('/user/:id', function (req, res, next) {
  var id = req.params.id;
  // ...
});

How can I predefine req.query and swap query parsers in Express 1?

You can set req.query in earlier middleware or mount a custom parser with the query parser setting.

This is handy when you need to coerce query values or support a non-standard format like qs.

Example of predefining:

app.use(function (req, res, next) {
  // Force all query values to be numbers when possible
  var raw = req.query;
  req.query = {};
  for (var key in raw) {
    var val = Number(raw[key]);
    req.query[key] = isNaN(val) ? raw[key] : val;
  }
  next();
});

Swapping the parser:

var qs = require('qs');
app.set('query parser', function (str) {
  return qs.parse(str);
});

After this, every request's req.query will be the result of qs.parse, giving you deep object support out of the box.

What new response methods does Express 1 add for cookies, redirects, and file streaming?

Express 1 introduces res.cookie(), res.clearCookie(), richer res.redirect() handling, and streaming support for res.sendfile().

Cookie helpers let you set attributes like maxAge or httpOnly in one call:

res.cookie('session', 'abc123', { maxAge: 900000, httpOnly: true });
res.clearCookie('session');

res.redirect() now respects the request's Accept header, returning text/plain or text/html as appropriate, and includes a human-readable status string in the body.

File streaming is more efficient: you can set a stream threshold and Express will pipe the file instead of buffering it.

app.get('/download', function (req, res) {
  res.sendfile('/path/to/large.zip', { maxAge: 0 });
});

These helpers reduce boilerplate and make common response patterns explicit.

Which view-related settings were fixed or added in Express 1?

Mounted apps now inherit the view engine setting, and the engine works correctly even when the view directory name contains a period.

Partial handling got smarter: Express can infer object names from the partial path, cache view-path lookups, and support array-like collections directly.

Dynamic helpers are now cached, improving render performance for frequently used locals.

Example of using a partial with inferred locals:

<%- partial('forum/post', post) %>

The template receives a post local automatically, and the lookup is cached after the first render.