Simple worker that does stuff in batches. Block passed to initializer should be a method that accepts list of things to work at a time

batch_worker.rb

class BatchWorker
  attr_reader :size
  def initialize(size, &block)
    @size = size

    @buf = []
    @block = block
  end

  def write(value)
    @buf << value
    if @buf.size >= @size
      @block.call(@buf)
      @buf.clear
    end
  end

  def finish
    @block.call(@buf)
  end
end

# w = BatchWorker.new(3) { |numbers| puts numbers.inspect }
# (1..10).each { |i| w.write(i) }
# => [1, 2, 3]
# => [4, 5, 6]
# => [7, 8, 9]
# w.finish
# => [10]