Easy way to create your own Rake task

Andrei Kaleshka

14 Mar 2012

TL;DR: use rails generator rails g task my_namespace my_task1 my_task2.

Some time ago I found a generator in Ruby on Rails’s sources to create a Rake task. There were no information about it anywhere. As a result, I decided to share my findings. This post will show you a simple and efficient method for generating them.

Several ways to create Rake tasks

There are at least two known approaches you can take:

1. Write it from scratch.
2. Copy and paste existing code and modify it as necessary.

The generator way to create Rake tasks

As it turns out, there is a third approach - utilize this Rake generator:

$ rails g task my_namespace my_task1 my_task2

It generates a scaffold for the new Rake tasks located within the lib/tasks/my_namespace.rake file:

namespace :my_namespace do
  desc "TODO"
  task :my_task1 => :environment do
  end

  desc "TODO"
  task :my_task2 => :environment do
  end
end

Now write some code inside the tasks’ body. This way, you save time creating the preparation code and concentrate on what matters.

Confirm that they are real and can be executed:

$ rake -T | grep my_namespace

The command outputs the following content:

rake my_namespace:my_task1  # TODO
rake my_namespace:my_task2  # TODO

It indicates two Rake tasks (my_task1 and my_task2) defined under the namespace my_namespace. However, they are empty and will do nothing until you add some code. The TODO comments remind you about that.

It has never been easier

The generator provides a skeleton for you. It’s easy to use and saves you time. You only need to focus on the task behavior.

Learning more

I’ve authored a book on the subject called Rake Task Management Essentials. To learn more about this remarkable tool, I recommend purchasing a copy. After reading, you will understand how to use Rake effectively in your daily tasks. The book guides you through easy-to-follow and practical examples.