All fibers

fiber_all.rb

########################
# First example

def find_in_batches
  index = 0
  chunk_size = 2
  while batch = query_batch(index, chunk_size)
    return if batch.length == 0
    yield batch
    index += 1
  end
end

def query_batch(index, chunk_size)
  range_beginning = index * chunk_size
  large_dataset[range_beginning...(range_beginning+2)]
end

def large_dataset
  [
    "Vhils",
    "AKACORLEONE",
    "Pixel Pancho",
    "+-",
    "Kruella D'Enfer",
    "Tamara Alves",
    "Add Fuel",
    "MAR",
    "Eime",
    "Bordalo II",
    "Felipe Pantone",
    "Ernest Zacharevic",
    "Wasted Rita",
    "Sainer"
  ]
end

########################
# Second example

def process_batch(batch)
  p batch
end

# this method runs in a background job
def complex_operation_in_background
  find_in_batches do |batch|
    # the complex operation on the given batch
    process_batch(batch)
  end
end

# Execution in the terminal
# >> complex_operation_in_background
# ["Vhils", "AKACORLEONE"]
# ["Pixel Pancho", "+-"]
# ["Kruella D'Enfer", "Tamara Alves"]
# ["Add Fuel", "MAR"]
# ["Eime", "Bordalo II"]
# ["Felipe Pantone", "Ernest Zacharevic"]
# ["Wasted Rita", "Sainer"]


########################
# Third example

def complex_operation_in_background_with_recursion(batch_index = 0)
  chunk_size = 2
  batch = query_batch(batch_index, chunk_size)
  return if batch.length == 0

  process_batch(batch)
  complex_operation_in_background_with_recursion(batch_index + 1)
end

# Execution in the terminal
# >> complex_operation_in_background_with_recursion
# ["Vhils", "AKACORLEONE"]
# ["Pixel Pancho", "+-"]
# ["Kruella D'Enfer", "Tamara Alves"]
# ["Add Fuel", "MAR"]
# ["Eime", "Bordalo II"]
# ["Felipe Pantone", "Ernest Zacharevic"]
# ["Wasted Rita", "Sainer"]


########################
# Fourth example

require "fiber"

def find_in_batches_with_fiber
  Fiber.new do
    index = 0
    chunk_size = 2
    while batch = query_batch(index, chunk_size)
      break if batch.length == 0
      Fiber.yield batch
      index += 1
    end
  end
end

def complex_operation_in_background_with_fibers(fiber = nil)
  fiber ||= find_in_batches_with_fiber

  if fiber.alive? && (batch = fiber.resume)
    process_batch(batch)
    complex_operation_in_background_with_fibers(fiber)
  end
end

# Execution in the terminal
# >> complex_operation_in_background_with_fibers
# ["Vhils", "AKACORLEONE"]
# ["Pixel Pancho", "+-"]
# ["Kruella D'Enfer", "Tamara Alves"]
# ["Add Fuel", "MAR"]
# ["Eime", "Bordalo II"]
# ["Felipe Pantone", "Ernest Zacharevic"]
# ["Wasted Rita", "Sainer"]