thread_iterator.rb

# frozen_string_literal: true

# ThreadIterator is a class that allows iterating over an array in groups using threads.
class ThreadIterator
  # Initialize the ThreadIterator with an array and a group size.
  #
  # @param array [Array] The array to iterate over.
  # @param group_size [Integer] The size of each group.
  def initialize(array, group_size)
    @array = array
    @group_size = group_size
    @mutex = Mutex.new
  end

  # Iterate over the array in groups and execute a block for each group.
  #
  # @yieldparam group [Array] The current group being processed.
  # @return [Array] The results from all threads.
  def each_group(&block)
    return enum_for(:each_group) unless block_given?

    threads = []
    results = []

    # Iterate over the array in groups and spawn a thread for each group
    @array.each_slice(@group_size) do |group|
      threads << Thread.new do
        result = block.call(group)
        synchronize { results.concat(result) if result }
      end
    end

    # Wait for all threads to finish
    threads.each(&:join)
    results
  end

  private

  # Synchronize access to shared resources using the mutex
  def synchronize(&block)
    @mutex.synchronize(&block)
  end
end

• https://gist.github.com/andersonbosa/e27eef638f173c81d4d0b42a5a30b7f2#file-thread_iterator-rb-L20
  antes de processar poderia colocar em queue e ai deixa as threads lidar com a queue

• Queue é a única estrutura "thread-safe"