lib/async/pool/resource.rb



# Copyright, 2017, by Samuel G. D. Williams. <http://www.codeotaku.com>
# 
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
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# furnished to do so, subject to the following conditions:
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# The above copyright notice and this permission notice shall be included in
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# 
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# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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require 'console/logger'

require 'async/notification'
require 'async/semaphore'

module Async
	module Pool
		# The basic interface required by a pool resource.
		class Resource
			# Constructs a resource.
			def self.call
				self.new
			end
			
			def initialize(concurrency = 1)
				@concurrency = concurrency
				@closed = false
				@count = 0
			end
			
			# @attr [Integer] The concurrency of this resource, 1 (singleplex) or more (multiplex).
			attr :concurrency
			
			# @attr [Integer] The number of times this resource has been used.
			attr :count
			
			# Whether this resource can be acquired.
			# @return [Boolean] whether the resource can actually be used.
			def viable?
				!@closed
			end
			
			# Whether the resource has been closed by the user.
			# @return [Boolean] whether the resource has been closed or has failed.
			def closed?
				@closed
			end
			
			# Close the resource explicitly, e.g. the pool is being closed.
			def close
				@closed = true
			end
			
			# Whether this resource can be reused. Used when releasing resources back into the pool.
			def reusable?
				!@closed
			end
		end
	end
end