simplest way to have Express serve a default page?

I looked briefly for the best practices for serving a public folder and specifying the default page to serve. After reviewing the 'Express middleware' documentation, my solution looks like the following,

var express = require('express');
var app = express();

var options = {
  index: "coming-soon.html"
};

app.use('/', express.static('app', options));

var server = app.listen(8081, function () {
  var host = server.address().address;
  var port = server.address().port;

  console.log('my app is listening at http://%s:%s', host, port);
});

It's weird that no one mentioned redirection.

app.get('/', function(req, res){
    res.redirect('/default.html');
});

This -of course- assumes that you have your 'default.html' at the public path. You can set your public path by using:

app.use(express.static(relative_path_to_project_root));

You could do something like this. Assuming its an html file that is relative to the .js file:

app.get('/', function(req, res){
    res.sendfile('default.html', { root: __dirname + "/relative_path_of_file" } );
});