example inline sinatra file

sinatra.rb

require 'sinatra'
require 'coffee_script'
require 'haml'
# configure do
#   set :bind, '0.0.0.0'
# end

js = DATA.read

get '/shibboleth.js' do
  coffee js
end

get '/' do
  haml %{!!!
%html
  %head
    %script{src: '/shibboleth.js'}
    %meta{content: 'initial-scale=1.0, maximum-scale=1.0', name: 'viewport'}
    :css
      body {
        font-size: 1.5em;
      }
      textarea {
        font-size: 1rem;
        width: 100%
      }
      #results {
        overflow-y:scroll;
      }
  %body
    %textarea eµ
    %button SHA256
    #results
}
end

__END__
#return Uint8Array
to_array = (str) ->
  new Uint8Array encodeURIComponent(str).match(/%[A-F0-9]{2}|./gi).map (c) ->
    if /^%/.test c
      parseInt(c.substr(1), 16)
    else
      c.charCodeAt(0)
to_hex = (digestValue) ->
  digestValue = new Uint8Array digestValue
  hex = ""
  i = 0
  len = digestValue.length
  while i < len
    zeropad = if (digestValue[i] < 0x10) then "0" else ""
    hex += zeropad + digestValue[i].toString(16)
    i++
  return hex
document.addEventListener('DOMContentLoaded', ->
  _crypto = window.msCrypto || window.crypto
  subtle = _crypto.subtle || _crypto.webkitSubtle
  show = (buf) ->
    document.querySelector('#results').textContent = to_hex buf
  document.querySelector('button').addEventListener('click', ->
    digestOp = subtle.digest(name: "SHA-256", to_array(document.querySelector('textarea').value))
    if Promise? && digestOp instanceof Promise
      digestOp.then (result) -> show result
    else
      digestOp.oncomplete = (evt) -> show evt.target.result
  )
)