Rosendo Build Status

Rosendo is a minimalistic and naive Sinatra reimplementation, without any dependencies other than the ruby socket library. It's a learning exercise on the HTTP specs, web servers, and how not to write software. It contains a (stupidly simple) HTTP server, a (rather incomplete) HTTP parser and a (really oversimplified) DSL.

Rosendo is not intended for any production use. Specifically, it's not intended as a Sinatra replacement. It has much less features, for sure much more bugs, and probably much worse performance. It's just a learning exercise.

This ongoing exercise is a game, whose rules (invented by myself) consist in reimplementing a web framework (Sinatra is far better for this purpose than my other favorite framework Rails, for obvious reasons) from scratch, using just Ruby. I wanted to prevent myself from using anything from the standard library, but probably making this without the socket library would be too much, so that's the only allowed exception. Still, no webrick, no erb, no nothing, and obviously no gems.

The rule doesn't apply to the tests though (I'm using minitest and Net::HTTP).

The purpose of the game/exercise comes from a reflection about how much software we usually depend on when writing our applications (just run bundle show in your latest Rails app if you don't believe me) and is double:

1) Remember that the software we take for granted and like to whine about some times, is actually great software we should thank for every minute we're using it. Trying to live without it for some time is a great way to achieve this.

2) At the same time, demystifying it. Not everybody can write such good web servers like the ones we use everyday, but everybody can write the simplest one. And understanding a bit how they work is a great thing, even if you're not obviously going to write a web server every time you want to write a web app. The same is true for every other piece of the stack.


Install it via Rubygems or Bundler, require it, and pretend it's Sinatra:

require 'rosendo'

class MyApp < Rosendo::App
  get "/" do
    "Hello, World!"
end!(port: 2000)


Sinatra features that Rosendo supports

  • Route mapping methods (get, post, ...)
  • Headers reading and setting
  • Basic params in URL (/hello/:name)
  • HTTP status code
  • Redirects
  • Params in query string

Sinatra features that Rosendo plans to support

  • Form params in request body
  • Templates

Sinatra features that Rosendo doesn't plan to support (for the moment)

  • Advanced route patterns (*, regular expressions, conditions, ...)
  • Filters
  • Helpers
  • Variables (set method)
  • Cookies
  • Sessions
  • Config blocks
  • Rack compliance
  • Streaming
  • Logging
  • Classic mode
  • Static files

See example.rb for some supported things.

Rosendo is also the name of the most charismatic Spanish rock singer and songwriter ever.

Rosendo Mercado


Released under the MIT license.