Active Batch

Active Batch allows the management and execution of batch of Active Jobs. It is useful when an action must be perform when and only when a list of tasks has been completed and you want to execute this list of tasks in parallel. It can also be seen as some kind of map / reduce on top of Active Job.

Installation

Compatible with Rails 4 only (Uses ActiveJob)

1. Add ActiveBatch to your Gemfile:

   gem 'active_batch'

2. And then execute:

   $ bundle

3. Generate a migration which will add the required tables to your database.

   $ rake active_batch:install:migrations

4. Run the migration.

   $ bundle exec rake db:migrate

Usage

Declare a job like so:

class MyBatchJob < ActiveJob::Base
  include ActiveBatch::BatchedJob

  queue_as :my_queue

  # Yields parameters to be used by each task
  self.each_work_unit(max)
    [0..max].each { |i| yield i }
  end

  # Actual work perform for each task
  def perform(i)
    result = expensive_computation(i)
    save_result(result) # This saves the result that will be passed to the "reduce" part (self.after_batch)
  end

  # Executed only once all tasks are complete
  def self.after_batch(max, results)
    reduce(results)
  end
end

Enqueue the whole batch like so:

MyBatchJob.perform_batch(100)

You can mount a dashboard with all the batches and their status in your config/routes.rb:

mount ActiveBatch::Engine, at: "batches"

Contributing

1. Fork it ( https://github.com/idolweb/active_batch/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request