class Sponges::Commander

This class concern is to send messages to supervisor. It's used to send messages like 'stop' or 'restart'

Attributes

store[R]

Public Class Methods

new(name, options = {}) click to toggle source
# File lib/sponges/commander.rb, line 12
def initialize(name, options = {})
  @name, @options = name, options
  @store = Sponges::Store.new(@name)
end

Public Instance Methods

decrement() click to toggle source

Decrement workers's pool by one.

# File lib/sponges/commander.rb, line 72
def decrement
  Sponges.logger.info "Runner #{@name} decrement message received."
  if supervisor_pid
    begin
      Process.kill :TTOU, supervisor_pid.to_i
    rescue Errno::ESRCH => e
      Sponges.logger.error e
    end
  else
    Sponges.logger.info "No supervisor found."
  end
end
increment() click to toggle source

Increment workers's pool by one.

# File lib/sponges/commander.rb, line 57
def increment
  Sponges.logger.info "Runner #{@name} increment message received."
  if pid = supervisor_pid
    begin
      Process.kill :TTIN, supervisor_pid.to_i
    rescue Errno::ESRCH => e
      Sponges.logger.error e
    end
  else
    Sponges.logger.info "No supervisor found."
  end
end
kill() click to toggle source

Kills the supervisor, and then all workers.

# File lib/sponges/commander.rb, line 19
def kill
  Sponges.logger.info "Runner #{@name} kill message received."
  stop :KILL
  children_pids.each do|pid|
    begin
      kill_process(:KILL, pid, "Worker")
    rescue Errno::ESRCH => e
      # Don't panic
    ensure
      store.delete_children pid
    end
  end
end
stop(signal = nil) click to toggle source

Stops supervisor, signal depends on options given by Boson.

# File lib/sponges/commander.rb, line 35
def stop(signal = nil)
  signal ||= gracefully? ? :HUP : :QUIT
  Sponges.logger.info "Runner #{@name} stop message received."
  if pid = supervisor_pid
    if @options[:timeout]
      begin
        Timeout::timeout(@options[:timeout]) do
          kill_process(signal, pid)
        end
      rescue Timeout::Error
        kill
      end
    else
      kill_process(signal, pid)
    end
  else
    Sponges.logger.info "No supervisor found."
  end
end

Private Instance Methods

children_pids() click to toggle source
# File lib/sponges/commander.rb, line 91
def children_pids
  @store.children_pids
end
gracefully?() click to toggle source
# File lib/sponges/commander.rb, line 109
def gracefully?
  !!@options[:gracefully]
end
kill_process(signal, pid, type = "Supervisor") click to toggle source
# File lib/sponges/commander.rb, line 95
def kill_process(signal, pid, type = "Supervisor")
  pid = pid.to_i
  begin
    Process.kill signal, pid
    while alive?(pid) do
      Sponges.logger.info "#{type} #{pid} still alive"
      sleep 0.5
    end
    Sponges.logger.info "#{type} #{pid} has stopped."
  rescue Errno::ESRCH => e
    # Don't panic
  end
end
supervisor_pid() click to toggle source
# File lib/sponges/commander.rb, line 87
def supervisor_pid
  @store.supervisor_pid
end