Class: ExaZK

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

Instance Method Summary collapse

Constructor Details

#initialize(mutex, zk_string, routes, data) ⇒ ExaZK

Returns a new instance of ExaZK.



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# File 'lib/exazk.rb', line 6

def initialize(mutex, zk_string, routes, data)
  @mutex = mutex
  @zk_string = zk_string
  @routes = routes
  @data = {
    hostname: Socket.gethostname,
    data: data
  }.to_json
  @zk = ZK.new(@zk_string)
end

Instance Method Details

#announce_routes ⇒ Object 



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# File 'lib/exazk.rb', line 28

def announce_routes
  @routes.map do |route|
    route % 'announce'
  end
end

#main_loop ⇒ Object 



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# File 'lib/exazk.rb', line 48

def main_loop
  withdraw_routes.each do |route|
    send_update(route)
  end unless mutex_exists?

  announce_routes.each do |route|
    send_update(route)
  end if mutex_exists?
end

#mutex_exists? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/exazk.rb', line 34

def mutex_exists?
  if @zk.exists?(@mutex)
    data = JSON.parse(@zk.get(@mutex).first)
    return true if data['hostname'] == Socket.gethostname
  else
    begin
      @zk.create(@mutex, "#{@data}", :ephemeral => true)
      return true
    rescue ZK::Exceptions::NodeExists
      return false
    end
  end
end

#send_update(route) ⇒ Object 



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# File 'lib/exazk.rb', line 17

def send_update(route)
  $stdout.write route
  $stdout.flush
end

#withdraw_routes ⇒ Object 



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# File 'lib/exazk.rb', line 22

def withdraw_routes
  @routes.map do |route|
    route % 'withdraw'
  end
end