Let us say that our app requires us to send both GET and POST requests to a particular URL such that the same block of code handles both verbs. It makes sense to define an extension that can handle our requirement, as we don’t want to define two routes with identical code.

SinatraExt

**  Creating Sinatra Extensions  **

Let us say that our app requires us to send both GET and POST requests to a particular URL such that the same block of code handles both verbs. It makes sense to define an extension that can handle our requirement, as we don’t want to define two routes with identical code.

Here is our code:

# post_get.rb
require 'sinatra/base'
module Sinatra
  module PostGet
    def post_get(route, &block)
      get(route, &block)
      post(route, &block)
    end
  end
  # now we just need to register it via Sinatra::Base
  register PostGet
end

Note: When creating extension and helper methods (as above), it’s considered a best practice to wrap those in a module and use the register method to let Sinatra figure out where to use those modules as mixins.

To use our custom Sinatra::PostGet extension, write this code:

# test.rb
require 'sinatra'
require './sinatra/post_get'

post_get '/' do
  "Hi #{params[:name]}"
end

Open a command window and run our Sinatra app:

$ ruby test.rb
INFO  WEBrick 1.3.1
INFO  ruby 2.0.0 (2013-05-14) [i386-mingw32]
== Sinatra/1.4.3 has taken the stage on 4567 for development with backup from WEBrick
INFO  WEBrick::HTTPServer#start: pid=6964 port=4567

Let's use cURL to send a GET request to our app. Open another command window and type:

$ curl -G http://localhost:4567
Hi world!

On the server console, you will see something like this:

127.0.0.1 - - [12/Jul/2013 09:17:57] "GET / HTTP/1.1" 200 9 0.0030
TALIM-PC - - [12/Jul/2013:09:17:57 India Standard Time] "GET / HTTP/1.1" 200 9

Now let's use cURL to send a POST request to our app:

$ curl -d hello http://localhost:4567
Hi world!

On the server console, you will see something like this:

127.0.0.1 - - [12/Jul/2013 09:19:58] "POST / HTTP/1.1" 200 9 0.0010
TALIM-PC - - [12/Jul/2013:09:19:58 India Standard Time] "POST / HTTP/1.1" 200 9


Success! We now have a custom extension that allows us to respond to two verbs in one route without duplicating any code.

Hat Tip: Konstantin Haase