Class: Omnom::Scheduler

Inherits:
Object
  • Object
show all
Defined in:
lib/omnom/scheduler.rb

Class Method Summary collapse

Class Method Details

.safely_run(name = nil) ⇒ Object

If many jobs run at once, we may exhaust the pool. This catches database connection timeouts and retries them after sleeping for a brief, random (to prevent multiple simultaneous queries) duration.



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# File 'lib/omnom/scheduler.rb', line 35

def self.safely_run(name=nil)
  attempts = 10
  min_sleep_seconds = 3
  max_sleep_seconds = 5
  did_run = false

  attempts.times do
    begin
      yield
      did_run = true
      break
    rescue ActiveRecord::ConnectionTimeoutError => e
      sleep(rand(min_sleep_seconds..(max_sleep_seconds * 1.0)))
    end
  end
  unless did_run
    description = ": #{name}" if name
    warn "Unable to safely run task#{description}"
  end
end

.start ⇒ Object 



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# File 'lib/omnom/scheduler.rb', line 3

def self.start
  scheduler = Rufus::Scheduler.start_new
  initial_run_in_seconds = 0
  Omnom.feeds.values.each do |feed|
    next if feed.sources.blank?
    feed.sources.each do |source|
      method = source.settings.slice(:cron, :every).keys.first
      raise "Please specify a schedule for #{source.class.name}" if method.blank?
      value = source.settings[method]
      
      # For sources that run often, go ahead and run them now to update them with new posts
      if method == :every
        scheduler.in "#{initial_run_in_seconds}s" do
          safely_run("Update #{source.class} in #{feed.class}") do
            feed.update_source(source)
          end
        end
        initial_run_in_seconds += 15
      end

      scheduler.send(method, value) do
        safely_run("Update #{source.class} in #{feed.class}") do
          feed.update_source(source)
        end
      end
    end
  end
  scheduler
end