sinatra_sse_reload.rb

# 
# (c) Baulin Roman 2015
# 
# http://stackoverflow.com/questions/1247125/how-to-get-sinatra-to-auto-reload-the-file-after-each-change
# https://github.com/rtomayko/shotgun

# sse http://www.w3schools.com/html/html5_serversentevents.asp
# sse with sinatra http://stackoverflow.com/questions/5227431/html5-server-sent-events-with-ruby-sinatra
# cool demo https://gist.github.com/rkh/1476463
# 
# bundle exec ruby sinatra_sse_reload.rb

require 'sinatra'

pid = Process.fork do
  require 'filewatcher'
  FileWatcher.new('./render.rb').watch do |filename|
    system "curl -G http://localhost:4567/reload"
  end
end

set server: 'thin', connections: []

get '/' do 
  load './render.rb'
  html
end 

get '/stream', provides: 'text/event-stream' do
  stream :keep_open do |out|
    settings.connections << out
    out.callback { settings.connections.delete(out) }
  end
end

get '/reload' do
  puts "reload, connections #{settings.connections.count}"
  settings.connections.each { |out| out << "data: update\n\n" }
  204
end