bundle-new/lib/bundler/parallel_workers/worker.rb

70 lines
1.7 KiB
Ruby

module Bundler
module ParallelWorkers
class Worker
POISON = Object.new
class WrappedException < StandardError
attr_reader :exception
def initialize(exn)
@exception = exn
end
end
# Creates a worker pool of specified size
#
# @param size [Integer] Size of pool
# @param func [Proc] job to run in inside the worker pool
def initialize(size, func)
@request_queue = Queue.new
@response_queue = Queue.new
prepare_workers size, func
prepare_threads size
trap("INT") { @threads.each {|i| i.exit }; stop_workers; exit 1 }
end
# Enqueue a request to be executed in the worker pool
#
# @param obj [String] mostly it is name of spec that should be downloaded
def enq(obj)
@request_queue.enq obj
end
# Retrieves results of job function being executed in worker pool
def deq
result = @response_queue.deq
if result.is_a?(WrappedException)
raise result.exception
end
result
end
# Stop the forked workers and started threads
def stop
stop_threads
stop_workers
end
private
# Stop the worker threads by sending a poison object down the request queue
# so as worker threads after retrieving it, shut themselves down
def stop_threads
@threads.each do
@request_queue.enq POISON
end
@threads.each do |thread|
thread.join
end
end
# To be overridden by child classes
def prepare_threads(size)
end
# To be overridden by child classes
def stop_workers
end
end
end
end