Rails 6: Dump Rails db to fixtures

db_fixtures_dump.rake

# Original from http://snippets.dzone.com/posts/show/4468 by MichaelBoutros
# Forked from https://gist.github.com/ecleel/3dc89a753bac6a54bf8d170f63256f19
#
# Optimized version which uses to_yaml for content creation and checks
# that models are ActiveRecord::Base models and not abstract class before trying to fetch
# them from database.
#
# Also supports nested resources and namespaces them correctly
#
# Tested in Rails 6.0.0
#
namespace :db do
  namespace :fixtures do
    desc 'Dumps all models into fixtures.'
    task :dump => :environment do

      models_path = Pathname.new(Rails.root + 'app/models')
      models = Dir.glob(Rails.root + 'app/models/**/*.rb').map do |model|
        dir_and_name = Pathname.new(model).relative_path_from(models_path).to_s
        dir_and_name.gsub(/\.rb$/,'').camelize
      end

      # include only ActiveRecord models and non-abstract class models
      models.select! do |m|
        m = m.constantize
        m.ancestors.include?(ActiveRecord::Base) && !m.abstract_class
      end

      puts "Found models: #{models.to_sentence}"
      puts "=> Dumping models:"
      models.each do |m|
        model = m.constantize
        model_file = "#{Rails.root}/test/fixtures/#{m.underscore.pluralize}.yml"

        puts "  \x1b[94m#{m}\x1b[0m to \x1b[94m#{Pathname.new(model_file).relative_path_from(Rails.root)}\x1b[0m"

        increment = 1
        entries = model.order(id: :asc).all

        FileUtils.mkdir_p(File.dirname(model_file))
        File.open(model_file, 'w') do |f|
          entries.each do |a|
            attrs = a.attributes
            attrs.delete_if { |_k, v| v.blank? }

            output = { m + '_' + increment.to_s => attrs }
            f << output.to_yaml.gsub(/^--- \n/,'') + "\n"

            increment += 1
          end
        end
      end
    end
  end
end