Using Server-Sent Events (SSE) in Ruby on Rails example

Goals

• Consider ways to process SSE connections in Ruby On Rails application
• Show how using Rack Hijacking API allows to avoid blocking web server threads

For more information read this article

Approaches

• ActionController::Live
• Rack Hijacking API (Full hijacking)
• Rack Hijacking API (Partial hijacking)

Setting Puma threads count

Change default value in 'config/puma.rb' file

threads_count = ENV.fetch("RAILS_MAX_THREADS") { 5 }

Or set RAILS_MAX_THREADS env variable when starting Rails server

RAILS_MAX_THREADS=5 rails s