Generate seed.rb from existing models and data #ruby #RoR #hha_ank

generate_seeds.rake

require 'benchmark'

namespace :db do
  desc "Generate a seed.rb file with all records from all models"
  task :generate_seed_file => :environment do
    #start timer
    time = Benchmark.realtime do
      seed_file = File.open("#{Rails.root}/tmp/seeds.rb", "w")

      # eager load to get all models
      Rails.application.eager_load!

      # Get all ActiveRecord models except for those in Rails internal namespaces
      models = ApplicationRecord.descendants.reject { |model| model.name =~ /^Rails/ }
      puts "Discovered #{models.count} models"
      models.each do |model|
        # Write the model name to the seed file
        seed_file.write("# #{model.name}\n")

        # Write each record to the seed file
        puts "Processing #{model.name}..."
        puts "Extracting data from #{model.all.count} records"
        puts "Extracting #{model.first.attributes.count} attributes from each record"
        model.all.each do |record|
          seed_file.write("#{model.name}.create(#{record.attributes.except("id", "created_at", "updated_at").to_s.gsub(/\=>/, ': ')})\n")
        end

        # Add a blank line between models
        seed_file.write("\n")
      end

      seed_file.close
    end

    puts "Seed file generated successfully at tmp/seeds.rb in #{time.round(2)} seconds."
  end
end