class Bundler::Worker

Constants

POISON

Attributes

name[R]

@return [String] the name of the worker

Public Class Methods

new(size, name, func) click to toggle source

Creates a worker pool of specified size

@param size [Integer] Size of pool @param name [String] name the name of the worker @param func [Proc] job to run in inside the worker pool

# File bundler/worker.rb, line 22
def initialize(size, name, func)
  @name = name
  @request_queue = Thread::Queue.new
  @response_queue = Thread::Queue.new
  @func = func
  @size = size
  @threads = nil
  @previous_interrupt_handler = nil
end

Public Instance Methods

deq() click to toggle source

Retrieves results of job function being executed in worker pool

# File bundler/worker.rb, line 41
def deq
  result = @response_queue.deq
  raise result.exception if result.is_a?(WrappedException)
  result
end

enq(obj) click to toggle source

Enqueue a request to be executed in the worker pool

@param obj [String] mostly it is name of spec that should be downloaded

# File bundler/worker.rb, line 35
def enq(obj)
  create_threads unless @threads
  @request_queue.enq obj
end

stop() click to toggle source

# File bundler/worker.rb, line 47
def stop
  stop_threads
end

Private Instance Methods

abort_threads() click to toggle source

# File bundler/worker.rb, line 80
def abort_threads
  Bundler.ui.debug("\n#{caller.join("\n")}")
  @threads.each(&:exit)
  exit 1
end

add_interrupt_handler() click to toggle source

# File bundler/worker.rb, line 107
def add_interrupt_handler
  @previous_interrupt_handler = trap("INT") { abort_threads }
end

apply_func(obj, i) click to toggle source

# File bundler/worker.rb, line 61
def apply_func(obj, i)
  @func.call(obj, i)
rescue Exception => e # rubocop:disable Lint/RescueException
  WrappedException.new(e)
end

create_threads() click to toggle source

# File bundler/worker.rb, line 86
def create_threads
  creation_errors = []

  @threads = Array.new(@size) do |i|
    Thread.start { process_queue(i) }.tap do |thread|
      thread.name = "#{name} Worker ##{i}" if thread.respond_to?(:name=)
    end
  rescue ThreadError => e
    creation_errors << e
    nil
  end.compact

  add_interrupt_handler unless @threads.empty?

  return if creation_errors.empty?

  message = "Failed to create threads for the #{name} worker: #{creation_errors.map(&:to_s).uniq.join(", ")}"
  raise ThreadCreationError, message if @threads.empty?
  Bundler.ui.info message
end

process_queue(i) click to toggle source

# File bundler/worker.rb, line 53
def process_queue(i)
  loop do
    obj = @request_queue.deq
    break if obj.equal? POISON
    @response_queue.enq apply_func(obj, i)
  end
end

remove_interrupt_handler() click to toggle source

# File bundler/worker.rb, line 111
def remove_interrupt_handler
  return unless @previous_interrupt_handler

  trap "INT", @previous_interrupt_handler
end

stop_threads() click to toggle source

Stop the worker threads by sending a poison object down the request queue so as worker threads after retrieving it, shut themselves down

# File bundler/worker.rb, line 69
def stop_threads
  return unless @threads

  @threads.each { @request_queue.enq POISON }
  @threads.each(&:join)

  remove_interrupt_handler

  @threads = nil
end