sinatra streaming

app.rb

require "sinatra"

get '/' do
  erb :index
end

get '/stream', provides: "text/event-stream" do
  puts "hi"
  stream(:keep_open) do |out|
    1000.times do |i|
      out << "data: #{i} bottle(s) on a wall...\n\n"
      sleep 0.5
    end
  end
end

index.erb

<script>
  var es = new EventSource('/stream');
  es.onmessage = function(e){
    console.log(e.data);
  }
</script>