Serve files using Rack TryStatic directly?

Question

I'm using Middleman to create a static site.

Middleman generates static html files into ./build directory.

Here's the config I'm currently using:

require 'rubygems'
require 'middleman'
require 'rack/contrib/try_static'

use Rack::TryStatic, :root => "build", :urls => %w[/], :try => ['.html']

run Middleman::Application.server

So Middleman is serving the static files right now. How can I make Rack::TryStatic handle the requests directly?

I tried to make it something like

run Rack::TryStatic, :root => "build", :urls => %w[/], :try => ['.html']

But it doesn't work is run only accepts 1 argument. And Rack::TryStatic requires 2 arguments, app and options to initialize, and I don't have any app.

How can I do this?

(And if it matters, I'm deploying to Heroku)

Answer 1

As you’ve noticed, a Rack middleware component such as Rack::TryStatic needs another app to pass requests onto. You could create a simple one to use that for example just returned a 404 response, such as:

app = lambda {|env| [404, {'Content-type' => 'text/plain'}, ['Not found']
run Rack::TryStatic.new app, :root => "build", :urls => %w[/], :try => ['.html']

or equivalently:

use Rack::TryStatic, :root => "build", :urls => %w[/], :try => ['.html']
run lambda {|env| [404, {'Content-type' => 'text/plain'}, ['Not found']]}

If you have your own 404 file, you could use rack-contrib’s Rack::NotFound instead of a custom end point of your own:

use Rack::TryStatic, :root => "build", :urls => %w[/], :try => ['.html']
run Rack::NotFound.new('path/to/your/404.html')

If you weren’t using the :try array of file extensions to try and serve, you could use Rack::File directly. Internally, Rack::TryStatic uses Rack::Static, which in turn uses Rack::File. Unlike TryStatic and Static, Rack::File is a Rack application in its own right, and so doesn’t need a separate app to pass requests to. Your config.ru would then simply be:

run Rack::File.new './build'

although this wouldn’t allow for “bare” requests to be served with the corresponding .html file — all requests would need to specify the whole file name.