Module: DistribCore::ReceivedSignals

Defined in:
lib/distrib_core/received_signals.rb

Overview

A handler for signal interruptions (like INT and TERM). Stores information about received signals.

Class Method Summary collapse

Class Method Details

.any? ⇒ TrueClass, FalseClass

Returns ‘true` when received any signal.

Returns:

  • (TrueClass, FalseClass) —

    ‘true` when received any signal



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# File 'lib/distrib_core/received_signals.rb', line 27

def any?
  signals.any?
end

.exit_code ⇒ Integer

Returns proper exit code based on received signal.

Returns:

  • (Integer) —

    proper exit code based on received signal



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# File 'lib/distrib_core/received_signals.rb', line 48

def exit_code
  return 0 if signals.empty?

  Signal.list[signals.first]
end

.force_int? ⇒ TrueClass, FalseClass

Returns ‘true` if ’INT’ was sent twice.

Returns:

  • (TrueClass, FalseClass) —

    ‘true` if ’INT’ was sent twice



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# File 'lib/distrib_core/received_signals.rb', line 38

def force_int?
  @force_int
end

.message ⇒ String

Returns human-readable message about received signals.

Returns:

  • (String) —

    human-readable message about received signals



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# File 'lib/distrib_core/received_signals.rb', line 43

def message
  "RECEIVED SIGNAL #{signals.to_a.join(', ')}." if any?
end

.received?(sig) ⇒ TrueClass, FalseClass

Returns ‘true` if signal `sig` was recieved.

Parameters:

  • sig (String)

Returns:

  • (TrueClass, FalseClass) —

    ‘true` if signal `sig` was recieved



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# File 'lib/distrib_core/received_signals.rb', line 33

def received?(sig)
  signals.member?(sig)
end

.signals ⇒ Set<String>

Returns list of received signals.

Returns:

  • (Set<String>) —

    list of received signals



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# File 'lib/distrib_core/received_signals.rb', line 55

def signals
  @signals ||= Set.new
end

.trap(sig) ⇒ Object

Defines trap for singlas and collects them. Exits after second ‘INT’

Examples:

::DistribCore::ReceivedSignals.trap('INT')

Parameters:

  • sig (String) —

    signal to trap



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# File 'lib/distrib_core/received_signals.rb', line 13

def trap(sig)
  Signal.trap(sig) do
    # Second SIGINT finishes the process immediately
    if sig == 'INT' && signals.member?('INT')
      @force_int = true
      puts 'Received second SIGINT. Exiting...'
      Kernel.exit(2) # 2 is exit code for SIGINT
    end
    puts "Received #{sig}"
    signals.add(sig)
  end
end