Custom Seed Data Using Rake in Ruby on Rails

Published in

pengenpaham

2 min readAug 19, 2022

By default, Ruby on Rails has a mechanism for seeding data with the app/db/seeds.rb file for the entire application.

But, sometimes we need to run spesific seed without running the entire seed application. In this case, we can solved it using custom rake to seed the data.

1. Create Rake File

# app/lib/tasks/custom_seed.rake# frozen_string_literal: truenamespace :db do
  namespace :seed do
    desc 'Load the custom seed data from
    db/seeds/my_custom_filename_seed.rb'
    
    task single: :environment do
      filename = Dir[File.join(Rails.root, 'db', 'seeds', "#{ENV['SEED']}.rb")][0]
      puts "Seeding #{filename}..."
      load(filename) if File.exist?(filename)
    end
  end
end

2. Create Seed File

Now, we can create spesific file for seeding spesific data. For example, in this article we created file app/db/seeds/posts_seed.rb for seeding data in model Post.

# app/db/seeds/posts_seed.rb# bundle exec rake db:seed:single SEED=posts_seedposts = [
  { name: 'Post 1', description: 'My post 1'},
  { name: 'Post 2', description: 'My post 2' },
  { name: 'Post 3', description: 'My post 3' }
 ]
posts.each do |post|
  puts "Creating post #{post[:name]}"
  Post.find_or_create_by(name: post[:name], description: post[:description])
end

3. Running Seed for Spesific File

After creating files in app/db/seeds/*.rb, we can execute it with this command.

Format :

bundle exec rake db:seed:single SEED=my_custom_filename_seed

Note : you can replace my_custom_filename_seed using your filename inside folder app/db/seeds/

Example :

bundle exec rake db:seed:single SEED=posts_seed

Thanks for reading 🍉 💻