ActiveJob as Service Worker

00_do_stuff_job.rb

# ActiveJob natively captures constructor arguments in an `@arguments` instance variable
# which is also exposed as an `arguments` property on each job instance.
#
# Calls to `perform_now` and `perform_later` both forward arguments to the constructor.
#
# For example, all of these invocation styles work.
#
#   result = DoStuffJob.new("foobar").perform # sync
#   result = DoStuffJob.new.perform("foobar") # sync
#   result = DoStuffJob.perform_now("foobar") # sync
#   DoStuffJob.perform_later("foobar")        # async
#
# Note that all of the synchronous invocations return the result of the `perform` method.
#
# This allows ActiveJob to serve the role of "service object"
# with the added benefit of supporting asynchronous/backgrounded invocations.
#
# Also, we can override the consuctor to take more control if needed.
#
class DoStuffJob < ApplicationJob
  def perform(message = nil)
    message ||= arguments.first
    # do stuff...
    "This is the result: #{message}"
  end
end

01_do_stuff_job.rb

# You can also rename the `perform` method to match business semantics if desired.
#
class DoStuffJob < ApplicationJob
  class << self
    alias_method :do_the_thing_now, :perform_now
    alias_method :do_the_thing_later, :perform_later
  end

  def perform(message = nil)
    message ||= arguments.first
    # do stuff...
    "This is the result: #{message}"
  end

  alias_method :do_the_thing, :perform
end

02_do_suff_job.rb

# Override the constructor if you need more control over initialization
#
# Examples:
#
#   DoStuffJob.new("foobar").perform
#   DoStuffJob.new("foobar").perform("override")
#   DoStuffJob.new.perform "foobar"
#   DoStuffJob.perform_now "foobar"
#
class DoStuffJob < ApplicationJob
  def initialize(message = nil)
    super

    @message = message
    # custom initialization code...
  end

  def perform(message = nil)
    message ||= @message
    raise ArgumentError, "message is required" unless message

    # do stuff...

    "This is the result: #{message}"
  end
end

03_do_stuff_job.rb

# Use keyword arguments to enhance the job's interface
#
# Examples:
#
#   DoStuffJob.new(message: "foobar").perform
#   DoStuffJob.new(message: "foobar").perform(message: "override")
#   DoStuffJob.new.perform message: "foobar"
#   DoStuffJob.perform_now message: "foobar"
#
class DoStuffJob < ApplicationJob
  def initialize(message: nil)
    super

    @message = message
    # custom initialization code...
  end

  def perform(message: nil)
    message ||= @message
    raise ArgumentError, "message is required" unless message

    # do stuff...

    "This is the result: #{message}"
  end
end