Class: Messaging::CLI

Inherits:
Object
  • Object
show all
Defined in:
lib/messaging/cli.rb

Overview

Starts up the consumer supervisor and handles signals

Constant Summary collapse

SIGNALS = 
%i[INT TERM QUIT].freeze

Instance Method Summary collapse

Constructor Details

#initialize ⇒ CLI

Returns a new instance of CLI.



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# File 'lib/messaging/cli.rb', line 11

def initialize
  @signal_queue = []
  @reader, @writer = IO.pipe
  @consumer_supervisor = Messaging::ConsumerSupervisor.new
end

Instance Method Details

#run ⇒ Object 



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# File 'lib/messaging/cli.rb', line 17

def run
  setup_signals
  consumer_supervisor.start
  wait_for_signal
end

#wait_for_signal ⇒ Object

See www.sitepoint.com/the-self-pipe-trick-explained/ for background on this



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# File 'lib/messaging/cli.rb', line 24

def wait_for_signal
  loop do
    case signal_queue.pop
    when *SIGNALS
      consumer_supervisor.stop
      break
    when "USR1"
      consumer_supervisor.status
    else
      ready = IO.select([reader, writer])

      # drain the self-pipe so it won't be returned again next time
      reader.read_nonblock(1) if ready[0].include?(reader)
    end
  end
end