rack-timeout-test.rb

#!/usr/bin/env ruby

require 'bundler/inline'

gemfile do
  source 'https://rubygems.org'

  gem 'thin'
  gem 'rack'
  gem 'rack-timeout'
end

$logger = Logger.new(STDERR)

class TimeoutCatcherMiddleware
  def initialize(app)
    @app = app
  end

  def call(env)
    $logger.info "Starting #{self.class.name}.."
    $logger.info "Invoking next middleware in stack"
    status, headers, body = @app.call(env)
    $logger.info "Retrieved response. Sending now."

    [status, headers, body]
  rescue StandardError => e
    $logger.error "Timeout exceeded. Showing error"
    $logger.error e.inspect
    ['500', {'Content-Type' => 'text/plain'}, [e.inspect]]
  end
end


app = Proc.new do |env|
  $logger.info "In app. Sleeping for 5 seconds."
  sleep 5
  ['200', {'Content-Type' => 'text/plain'}, ['Request Succeeded (slowly)']]
end

Thin::Server.start('127.0.0.1', 3000) do
  use Rack::CommonLogger, logger: $loggger
  #use Rack::ShowExceptions
  use TimeoutCatcherMiddleware
  use Rack::Timeout, service_timeout: 2
  use Rack::Lock # ensure requests are serial
  map '/' do
    run app
  end
end