Export local db to JSON and load that dump back to the db later

dump_db_to_json.rb

namespace :json do
  desc 'Export all data to JSON files'
  task :export => :environment do
    Rails.application.eager_load!

    ApplicationRecord.descendants.each do |model|
      next if model.table_name.nil? || model.table_name == ''
      begin
        data = model.all
        next if data == []
        file = File.open(File.join(Rails.root, 'db', 'export', "#{model.table_name}.json"), 'w')
        file.write data.to_json
        file.close
      rescue => e
        puts e
      end
    end
  end

  desc 'Import all data from JSON files'
  task :import => :environment do
    Dir["./db/export/*.json"].each do |file|

      table_name = file.split('/').last.split('.').first
      class_type = table_name.classify.constantize
      models = JSON.parse(File.read(file))
      models.each do |model|
        model_var = class_type.new(model)
        model_var.save
      end
    end
  end

end