Request timeout handling with Rack::Timeout

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                  Rails.application.config.middleware.insert_before(
  Rack::Runtime,
  Rack::Timeout,
  service_timeout: 15  # 15 seconds
)

# Log timeout errors
Rack::Timeout.register_state_change_observer(:logger) do |env, info|
  if info[:state] == :timed_out
    Rails.logger.error("Request timeout: #{env['REQUEST_METHOD']} #{env['PATH_INFO']} exceeded 15s")
  end
end

                  class ApplicationController < ActionController::Base
  rescue_from Rack::Timeout::RequestTimeoutException, with: :handle_timeout

  private

  def handle_timeout
    render json: {
      error: 'REQUEST_TIMEOUT',
      message: 'The request took too long to process'
    }, status: :service_unavailable
  end
end

Long-running requests tie up worker threads and degrade overall application responsiveness. Rack::Timeout enforces request timeouts at the Rack layer, killing requests that exceed configured limits. I set conservative timeouts (15-30 seconds) and handle Rack::Timeout::RequestTimeoutException to return proper 503 Service Unavailable responses. Timeouts protect against slow database queries, hung external API calls, or resource exhaustion. The challenge is distinguishing between legitimately slow operations and bugs—I use monitoring to track timeout rates and investigate patterns. For known slow operations like report generation, I move them to background jobs rather than fighting with timeout configuration.

Alex Kumar

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Request timeout handling with Rack::Timeout

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