Class: Lockistics::Lock

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

Constant Summary collapse

LUA_ACQUIRE = 
"return redis.call('setnx', KEYS[1], 1) == 1 and redis.call('expire', KEYS[1], KEYS[2]) and 1 or 0"

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(key, options = {}) ⇒ Lock

Returns a new instance of Lock.



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# File 'lib/lockistics/lock.rb', line 11

def initialize(key, options={})
  @key     = key
  @options = Lockistics.configuration.lock_defaults.merge(options)
  @options[:expire] = 999_999_999 unless @options[:expire].to_i > 0 # :expire => false
  @exceeded_before_release = false
  @lock_retries = 0
end

Instance Attribute Details

#key ⇒ Object

Returns the value of attribute key.



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# File 'lib/lockistics/lock.rb', line 7

def key
  @key
end

#lock_retries ⇒ Object

Returns the value of attribute lock_retries.



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# File 'lib/lockistics/lock.rb', line 7

def lock_retries
  @lock_retries
end

#options ⇒ Object

Returns the value of attribute options.



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# File 'lib/lockistics/lock.rb', line 7

def options
  @options
end

Instance Method Details

#acquire_lock ⇒ Object 



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# File 'lib/lockistics/lock.rb', line 19

def acquire_lock
  return true if options[:pass_through]
  if got_lock?
    true
  elsif options[:wait]
    wait_for_lock
  else
    false
  end
end

#exceeded_before_release? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/lockistics/lock.rb', line 44

def exceeded_before_release?
  @exceeded_before_release
end

#namespaced_key ⇒ Object 



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# File 'lib/lockistics/lock.rb', line 53

def namespaced_key
  @namespaced_key ||= "#{Lockistics.configuration.namespace}.lock.#{key}"
end

#release_lock ⇒ Object 



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# File 'lib/lockistics/lock.rb', line 48

def release_lock
  return true if options[:pass_through]
  @exceeded_before_release = redis.del(namespaced_key) == 0
end

#wait_for_lock ⇒ Object 



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# File 'lib/lockistics/lock.rb', line 30

def wait_for_lock
  until got_lock?
    @lock_retries += 1
    if lock_retries <= options[:retries]
      sleep options[:sleep]
    elsif options[:raise]
      raise LockTimeout, "while waiting for #{key}"
    else
      return false
    end
  end
  true
end