domininik/same_site_cookie.rb

## same_site_cookie.rb
# frozen_string_literal: true

# 1. run server with `ruby same_site_cookie.rb`
# 2. visit http://a.lvh.me:3000
# 3. submit form
# 4. you are redirected to http://b.local.gd:3000/cookie where the cookie should be set
# 5. you are redirected to http://b.local.gd:3000 where you can see if cookie is in place

require 'webrick'

SITE_A = 'a.lvh.me'
SITE_B = 'b.local.gd'
LISTEN_PORT = 3000
COOKIES = %w[Chocolate Oreo Shortbread Oatmeal Gingerbread Macaron Butter Wafer
             Fortune Almond Biscuit Stroopwafel Speculaas]

def cookie
  @visit_count ||= 0
  cookie = COOKIES[@visit_count % COOKIES.length]
  @visit_count += 1
  cookie
end

server = WEBrick::HTTPServer.new(Port: LISTEN_PORT)

trap('INT') { server.shutdown }

site_a = WEBrick::HTTPServer.new(ServerName: SITE_A, Port: LISTEN_PORT, DoNotListen: true)
site_b = WEBrick::HTTPServer.new(ServerName: SITE_B, Port: LISTEN_PORT, DoNotListen: true)

site_a.mount_proc '/' do |req, res|
  if req.path == '/'
    if req.request_method == 'POST'
      res.set_redirect(WEBrick::HTTPStatus::Found, "http://#{SITE_B}:#{LISTEN_PORT}/cookie")
    else
      res.body = <<~HTML
        <!DOCTYPE html>
        <html>
        <head>
          <title>Missing Cookie Example</title>
        </head>
        <body>
          <form action="/" method="post">
            <button type="submit">Submit form</button>
          </form>
        </body>
        </html>
      HTML
    end
  else
    res.status = 404
  end
end

visit_count = 0

site_b.mount_proc '/' do |req, res|
  if req.path == '/cookie'
    res['Set-Cookie'] = "cookie=#{cookie}; path=/; HttpOnly; SameSite=Lax"
    res.set_redirect(WEBrick::HTTPStatus::Found, "http://#{SITE_B}:#{LISTEN_PORT}/")
  elsif req.path == '/'
    res.body = <<~HTML
      <!DOCTYPE html>
      <html>
      <head>
        <title>Missing Cookie Example</title>
      </head>
      <body>
        <p>"Hello Visitor, you brought a #{req['Cookie']}"</p>
        <p><a href="http://#{SITE_A}:#{LISTEN_PORT}/">Retry</a></p>
      </body>
      </html>
    HTML
  else
    res.status = 404
  end
end

server.virtual_host(site_a)
server.virtual_host(site_b)
server.start
	# frozen_string_literal: true

	# 1. run server with `ruby same_site_cookie.rb`
	# 2. visit http://a.lvh.me:3000
	# 3. submit form
	# 4. you are redirected to http://b.local.gd:3000/cookie where the cookie should be set
	# 5. you are redirected to http://b.local.gd:3000 where you can see if cookie is in place

	require 'webrick'

	SITE_A = 'a.lvh.me'
	SITE_B = 'b.local.gd'
	LISTEN_PORT = 3000
	COOKIES = %w[Chocolate Oreo Shortbread Oatmeal Gingerbread Macaron Butter Wafer
	Fortune Almond Biscuit Stroopwafel Speculaas]

	def cookie
	@visit_count \|\|= 0
	cookie = COOKIES[@visit_count % COOKIES.length]
	@visit_count += 1
	cookie
	end

	server = WEBrick::HTTPServer.new(Port: LISTEN_PORT)

	trap('INT') { server.shutdown }

	site_a = WEBrick::HTTPServer.new(ServerName: SITE_A, Port: LISTEN_PORT, DoNotListen: true)
	site_b = WEBrick::HTTPServer.new(ServerName: SITE_B, Port: LISTEN_PORT, DoNotListen: true)

	site_a.mount_proc '/' do \|req, res\|
	if req.path == '/'
	if req.request_method == 'POST'
	res.set_redirect(WEBrick::HTTPStatus::Found, "http://#{SITE_B}:#{LISTEN_PORT}/cookie")
	else
	res.body = <<~HTML
	<!DOCTYPE html>
	<html>
	<head>
	<title>Missing Cookie Example</title>
	</head>
	<body>
	<form action="/" method="post">
	<button type="submit">Submit form</button>
	</form>
	</body>
	</html>
	HTML
	end
	else
	res.status = 404
	end
	end

	visit_count = 0

	site_b.mount_proc '/' do \|req, res\|
	if req.path == '/cookie'
	res['Set-Cookie'] = "cookie=#{cookie}; path=/; HttpOnly; SameSite=Lax"
	res.set_redirect(WEBrick::HTTPStatus::Found, "http://#{SITE_B}:#{LISTEN_PORT}/")
	elsif req.path == '/'
	res.body = <<~HTML
	<!DOCTYPE html>
	<html>
	<head>
	<title>Missing Cookie Example</title>
	</head>
	<body>
	<p>"Hello Visitor, you brought a #{req['Cookie']}"</p>
	<p><a href="http://#{SITE_A}:#{LISTEN_PORT}/">Retry</a></p>
	</body>
	</html>
	HTML
	else
	res.status = 404
	end
	end

	server.virtual_host(site_a)
	server.virtual_host(site_b)
	server.start