Testing infinite responses with HEAD requests

app.rb

#!/usr/bin/env ruby

require 'bundler/setup'
require 'sinatra/base'

class App < Sinatra::Base

  get '/' do
    [200, {}, ('A'..)]
  end

end

App.run!(server: ARGV[0] || 'webrick')

Gemfile

source 'https://rubygems.org/'

gem 'sinatra', '~> 2.0'
gem 'webrick'
gem 'thin'
gem 'puma'
gem 'unicorn'

gistfile1.txt

$ ./app.rb 
$ curl --head http://localhost:4567/
HTTP/1.1 200 OK
Content-Type: text/html;charset=utf-8
X-Xss-Protection: 1; mode=block
X-Content-Type-Options: nosniff
X-Frame-Options: SAMEORIGIN
Server: WEBrick/1.7.0 (Ruby/3.1.2/2022-04-12)
Date: Mon, 17 Oct 2022 21:20:32 GMT
Content-Length: 0
Connection: Keep-Alive

$ ./app.rb thin
$ curl --head http://localhost:4567/
HTTP/1.1 200 OK
Content-Type: text/html;charset=utf-8
X-XSS-Protection: 1; mode=block
X-Content-Type-Options: nosniff
X-Frame-Options: SAMEORIGIN
Connection: close
Server: thin

$ ./app puma
Content-Type: text/html;charset=utf-8
X-XSS-Protection: 1; mode=block
X-Content-Type-Options: nosniff
X-Frame-Options: SAMEORIGIN
Content-Length: 0