Class: DistributedMutex

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

Direct Known Subclasses

GlobalMutex, MySQLMutex

Constant Summary collapse

DEFAULT_TIMEOUT = 
1
DEFAULT_EXCEPTION_ON_TIMEOUT = 
false

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(key, timeout = DEFAULT_TIMEOUT, exception_on_timeout = DEFAULT_EXCEPTION_ON_TIMEOUT) ⇒ DistributedMutex

Returns a new instance of DistributedMutex.



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# File 'lib/distributed_mutex.rb', line 12

def initialize(key, timeout = DEFAULT_TIMEOUT, exception_on_timeout = DEFAULT_EXCEPTION_ON_TIMEOUT)
  @key = key
  @timeout = timeout
  @locked = false
  @exception_on_timeout = exception_on_timeout
end

Instance Attribute Details

#exception_on_timeout ⇒ Object (readonly)

Returns the value of attribute exception_on_timeout.



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# File 'lib/distributed_mutex.rb', line 9

def exception_on_timeout
  @exception_on_timeout
end

#key ⇒ Object (readonly)

Returns the value of attribute key.



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# File 'lib/distributed_mutex.rb', line 9

def key
  @key
end

#timeout ⇒ Object (readonly)

Returns the value of attribute timeout.



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# File 'lib/distributed_mutex.rb', line 9

def timeout
  @timeout
end

Class Method Details

.synchronize(key, timeout = DEFAULT_TIMEOUT, exception_on_timeout = DEFAULT_EXCEPTION_ON_TIMEOUT, &block) ⇒ Object 



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# File 'lib/distributed_mutex.rb', line 73

def self.synchronize(key, timeout = DEFAULT_TIMEOUT, exception_on_timeout = DEFAULT_EXCEPTION_ON_TIMEOUT, &block)
  mutex = new(key, timeout, exception_on_timeout)
  mutex.synchronize(&block)
end

Instance Method Details

#excluse_unlock ⇒ Object 



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# File 'lib/distributed_mutex.rb', line 10

alias excluse_unlock unlock

#lock ⇒ Object 



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# File 'lib/distributed_mutex.rb', line 19

def lock
  @locked = get_lock
  if true == @locked
    true
  else
    if @exception_on_timeout
      raise MutexLockTimeout.new
    else
      false
    end
  end
end

#locked? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/distributed_mutex.rb', line 32

def locked?
  @locked
end

#synchronize(&block) ⇒ Object 



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# File 'lib/distributed_mutex.rb', line 36

def synchronize(&block)
  if self.lock
    begin
      yield
    ensure
      self.unlock
    end
    true
  else
    false
  end
end

#try_lock ⇒ Object 



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# File 'lib/distributed_mutex.rb', line 49

def try_lock
  was_locked = nil
  begin
    self.lock
    was_locked = locked?
  ensure
    self.unlock
  end
  was_locked
end

#unlock ⇒ Object 



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# File 'lib/distributed_mutex.rb', line 60

def unlock
  if locked?
    if release_lock
      @locked = false
      true
    else
      raise MutexLockReleaseFailure
    end
  else
    false
  end
end