Robot Has No Heart

Xavier Shay blogs here

A robot that does not have a heart

Blocking (synchronous) calls in Goliath

Posting for my future self. A generic function to run blocking code in a deferred thread and resume the fiber on completion, so as not to block the reactor loop.

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def blocking(&f)
  fiber = Fiber.current
  result = nil
  EM.defer(f, ->(x){
    result = x
    fiber.resume
  })
  Fiber.yield
  result
end

Usage

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class MyServer < Goliath::API
  def response(env)
    blocking { sleep 1 }
    [200, {}, 'Woken up']
  end
end
A pretty flower Another pretty flower