Module: WebFetch::EventMachineHelpers

Included in:
Server
Defined in:
lib/web_fetch/concerns/event_machine_helpers.rb

Overview

EventMachine layer-specific helpers

Instance Method Summary collapse

Instance Method Details

#apply_callbacks(request) ⇒ Object 



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# File 'lib/web_fetch/concerns/event_machine_helpers.rb', line 19

def apply_callbacks(request)
  request[:deferred].callback do
    Logger.debug("HTTP fetch complete for uid: #{request[:uid]}")
    save_response_time(request)
    request[:succeeded] = true
  end

  request[:deferred].errback do
    Logger.debug("HTTP fetch failed for uid: #{request[:uid]}")
    save_response_time(request)
    request[:failed] = true
  end
end

#request_async(target) ⇒ Object 



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# File 'lib/web_fetch/concerns/event_machine_helpers.rb', line 6

def request_async(target)
  request = target[:request]
  target[:start_time] = Time.now.utc
  async_request = EM::HttpRequest.new(request[:url])
  method = request.fetch(:method, 'GET').downcase.to_sym
  async_request.public_send(
    method,
    head: request[:headers],
    query: request.fetch(:query, {}),
    body: request.fetch(:body, nil)
  )
end

#save_response_time(request) ⇒ Object 



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# File 'lib/web_fetch/concerns/event_machine_helpers.rb', line 53

def save_response_time(request)
  request[:response_time] = Time.now.utc - request[:start_time]
end

#tick_loop(request, response) ⇒ Object 



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# File 'lib/web_fetch/concerns/event_machine_helpers.rb', line 37

def tick_loop(request, response)
  # XXX There may be a much nicer way to wait for an async task to complete
  # before returning a response but I couldn't figure it out, so I used
  # EM.tick_loop which effectively does the same as a Twisted deferred
  # callback chain, just much more explicitly.
  EM.tick_loop do
    if request[:succeeded]
      succeed(request, response)
      :stop
    elsif request[:failed]
      fail_(request, response)
      :stop
    end
  end
end

#wait_for_response(request, response) ⇒ Object 



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# File 'lib/web_fetch/concerns/event_machine_helpers.rb', line 33

def wait_for_response(request, response)
  tick_loop(request, response)
end