A simple Goliath server that sends data to client using SSE after receiving a message on a redis pubsub channel

goliath_redis_server_sent_events.rb

require 'goliath'

require 'em-hiredis'

class EventGenerator < Goliath::API
  def response(env)

    redis = EM::Hiredis.connect
    redis.subscribe(:one)

    redis.on(:message) { |channel, message|
      puts [:message, channel, message]
      # env.stream_send(["event:signup", "data:signup event ##{rand(100)}\n\n"].join("\n"))
      env.stream_send("data:received message on <b>#{channel}</b> with content <i>#{message}</i>\n\n")
    }
    
    streaming_response(200, {'Content-Type' => 'text/event-stream'})
  end
end

class StatsGenerator < Goliath::API
  def response(env)
    [200, {}, "Hello World"]
  end
end

class SSE < Goliath::API
  use Rack::Static, :urls => ["/index.html"], :root => Goliath::Application.app_path("public")

  get "/events" do
    run EventGenerator.new
  end
end