Module: Mongoid::Lock

Extended by:
Semaphore
Defined in:
lib/mongoid/lock.rb,
lib/mongoid/lock/synch_methods.rb

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Semaphore

reset_semaphore!, sema_count, sema_down, sema_ready?, sema_up

Class Method Details

.included(base) ⇒ Object 



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# File 'lib/mongoid/lock.rb', line 14

def self.included(base)
  base.class_eval do
    include Mongoid::Semaphore
    default_sema_count 1
    field :used_by, :type => String, :default => nil
  end
end

Instance Method Details

#lock_acquire ⇒ Object 



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# File 'lib/mongoid/lock/synch_methods.rb', line 10

def lock_acquire
  self.sema_down
  if (self.sema_ready?)
    self.set(:used_by, "#{Socket.hostname}:#{Process.pid}")
  else
    self.sema_up
    raise Mongoid::Semaphore::UnsynchronizedAccess.new(self.sema_count, "Lock in Use! (#{self.used_by})")
  end
end

#lock_release ⇒ Object 



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# File 'lib/mongoid/lock/synch_methods.rb', line 20

def lock_release
  if (self.used_by == "#{Socket.hostname}:#{Process.pid}")
    self.sema_up
    self.set(:used_by, nil)
  end
end

#reset_lock! ⇒ Object 



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# File 'lib/mongoid/lock/synch_methods.rb', line 6

def reset_lock!
  self.update_attributes!({:sema_count => __semaphore_initial_count, :used_by => nil})
end

#synchronized(&block) ⇒ Object 



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# File 'lib/mongoid/lock/synch_methods.rb', line 28

def synchronized(&block)
  self.lock_acquire
  begin
    block.call()
  ensure
    self.lock_release
  end
end

#try_synchronized(&try_block) ⇒ Object 



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# File 'lib/mongoid/lock/synch_methods.rb', line 37

def try_synchronized(&try_block)
  return false unless self.sema_ready?
  begin
    self.synchronized do
      try_block.call()
    end
    return true
  rescue Mongoid::Semaphore::UnsynchronizedAccess => ua
    return false
  end
end

#used_by ⇒ Object

> Volatile Access, Reload to Ensure state



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# File 'lib/mongoid/lock.rb', line 8

def used_by
  self.save
  self.reload
  return super
end