Qe

A simple interface over several background job libraries like Resque, Sidekiq and DelayedJob.

In this wild world where a new asynchronous job processing library is released every once in a while, Qe tries to keep a unified interface that works with the most famous libraries:

• Sidekiq
• Resque
• DelayedJob
• Qu
• Beanstalk/Backburner

To set the adapter, just load the file according to your adapter:

require "qe/resque"
require "qe/qu"
require "qe/delayed_job"
require "qe/beanstalk"

You also need to require the library you're going to use. If you're using Rails with Bundler, you can simple require the correct file and dependency.

source :rubygems
gem "rails", "3.2.8"

gem "sidekiq"
gem "qe", :require => "qe/sidekiq"

gem "resque"
gem "qe", :require => "qe/resque"

gem "qu"
gem "qe", :require => "qe/qu"

gem "backburner"
gem "qe", :require => "qe/beanstalk"

Create a worker that will send e-mails through ActionMailer.

class MailerWorker
  include Qe::Worker

  def perform
    Mailer.public_send(options[:mail], options).deliver
  end
end

Define our Mailer class.

class Mailer < ActionMailer::Base
  def welcome(options)
    @options = options
    mail :to => options[:email]
  end
end

Enqueue a job to be processed asynchronously.

MailerWorker.enqueue({
  :mail => :welcome,
  :email => "john@example.org",
  :name => "John Doe"
})

You can specify when this job must be processed by setting the :run_at option.

MailerWorker.enqueue({
  :mail => :follow_up,
  :email => "john@example.org",
  :name => "John Doe",
  :run_at => 5.days.from_now
})

Sometimes setting the queue name is important.

class HelloWorker
  include Qe::Worker

  queue :hello
end

Sometimes you want to create several actions in a single worker, just because is easier. Instead of manually dispatch the action on your perform method, you can just add the Qe::Action module.

class NotificationWorker
  include Qe::Worker
  include Qe::Action

  def shutdown
    puts options[:message]
  end

  def startup
    puts options[:message]
  end

  def default
    puts options[:message]
  end
end

Now, you can just enqueue jobs by defining the :action option. If no action is defined, then the default is executed.

NotificationWorker.enqueue(:action => :shutdown, :message => "shutting down")
NotificationWorker.enqueue(:action => :startup, :message => "starting up")
NotificationWorker.enqueue(:message => "wat?")

The action must be a existing public method. If not defined, Qe::Action::MissingActionError exception is raised.

When you're working in internationalized app, you need to perform some jobs with the correct locale set (sending an e-mail, maybe?). Instead of doing it manually, you can just use the Qe::Locale extension.

This extension will set the :locale option when you enqueue some job and set it to I18n.locale when you perform it. Just include it after the Qe::Worker module.

class MailerWorker
  include Qe::Worker
  include Qe::Locale

  def perform
    Mailer.public_send(options[:mail], options).deliver
  end
end

This approach is good enough, but if you're using ActionMailer, try the Qe::ActionMailer instead, combining this extension as well.

Qe comes with an extension to send e-mails through ActionMailer. You can set the mailer and which mail will be sent.

class Mailer < ActionMailer::Base
  def welcome(options)
    @options = options
    mail :to => options[:email]
  end
end

class MailerWorker
  include Qe::Worker
  include Qe::ActionMailer
  include Qe::Locale

  def mailer
    Mailer
  end
end

MailerWorker.enqueue(
  :mail => :welcome,
  :name => "John Doe",
  :email => "john@example.org"
)

If the mailer() method isn't defined, the Qe::ActionMailer::AbstractMethodError exception will be raised.

If the :mail option isn't defined, the Qe::ActionMailer::MissingMailNameError exception will be raised.

You can set Sidekiq options by using the method Sidekiq::Worker.options.

require 'qe/sidekiq'

class NonRetryableWorker
  include Qe::Worker
  options retry: false

  def perform
    # do something...
  end
end

Qe comes with development support. Instead of starting up workers on development environment, you can use the Qe::Immediate adapter, which executes your worker right away!

Qe.adapter = Qe::Immediate

If you're using Rails, you can add the line above to your config/environments/development.rb file.

Qe also comes with testing support. Just require the qe/testing.rb file and a fake queuing adapter will be used. All enqueued jobs will be stored at Qe.jobs. Note that this method is only available on testing mode.

require "qe/testing"
Qe.adapter = Qe::Testing

If you are using RSpec, you can require the qe/testing/rspec.rb file instead. This will reset Qe.jobs before every spec and will add a enqueue matcher.

# Add the following like to your spec_helper.rb file
require "qe/testing/rspec"

describe "Enqueuing a job" do
  it "enqueues job" do
    expect {
      # do something
    }.to enqueue(MailerWorker).with(:email => "john@example.org")
  end
end

• Nando Vieira (http://nandovieira.com.br)

(The MIT License)

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.