Ruby Thread#stop / #Thread.stop? doesn't work how you might think.

thread_sleep_with_custom_state.rb

# This does work because a my custom thread status is unambiguous.
#
# However, you may notice that setting the status and sleeping are not atomic.

require "net/http"

responses = []

thread = Thread.new do
  Thread.current[:what_i_am_doing] = "starting"
  responses << Net::HTTP.get(URI.parse("https://zendesk.com"))
  Thread.current[:what_i_am_doing] = "stopping"

  sleep # sleep/wakeup seems nicer then stop/wakeup, also reflects value of Thread#status => "sleep"

  Thread.current[:what_i_am_doing] = "just woke up"
  responses << Net::HTTP.get(URI.parse("https://zendesk.com"))
  Thread.current[:what_i_am_doing] = "all done"
end

until thread[:what_i_am_doing] == "stopping" # guaranteed to wait for the request to finish
  sleep(0.001)
end

puts "#{responses.size == 1}: Thread has made the first request and stopped"
puts "#{thread.inspect.include?("sleep>")}: Thread is now having a regular sleep"

thread.wakeup
thread.join(_timeout = 5) # Hopefully that's long enough for the request

puts "#{responses.size == 2}: Thread made both requests"
puts "#{thread.inspect.include?("dead")}: Thread should be dead by now"
puts "#{thread[:what_i_am_doing] == "all done"}: Thread never woke up"

thread_stop.rb

# This doesn't always work because Thread#status is ambiguous

require "net/http"

responses = []

thread = Thread.new do
  Thread.current[:what_i_am_doing] = "starting"
  responses << Net::HTTP.get(URI.parse("https://zendesk.com"))
  Thread.current[:what_i_am_doing] = "stopping"
  Thread.stop
  Thread.current[:what_i_am_doing] = "just woke up"
  responses << Net::HTTP.get(URI.parse("https://zendesk.com"))
  Thread.current[:what_i_am_doing] = "all done"
end

until thread.stop? # Returns true when blocked on IO
  sleep(0.001) # any amount of sleep helps thread switching but using next will be slower
end

thread.wakeup # Too early, the thread hasn't stopped yet
thread.join(_timeout = 5) # Give it as long as you like, it's stopped.

puts "#{responses.size == 1}: Thread only ever makes the first request"
puts "#{thread.inspect.include?("sleep_forever")}: Thread is now sleeping forever in stopped position"
puts "#{thread[:what_i_am_doing] == "stopping"}: Thread never woke up"