Add column comment from I18n

add_column_comment_from_i18n.rb

class AddColumnCommentFromI18n < ActiveRecord::Migration[6.0]
  def up
    table_with_columns.each do |table_name, columns|
      columns.map(&:name).each do |column_name|
        next unless I18n.exists?("activerecord.attributes.#{table_name.singularize}.#{column_name}")
        change_column_comment(
          table_name,
          column_name,
          I18n.t("activerecord.attributes.#{table_name.singularize}.#{column_name}"),
        )
      end
    end
  end

  def down
    table_with_columns.each do |table_name, columns|
      columns.map(&:name).each do |column_name|
        next unless I18n.exists?("activerecord.attributes.#{table_name.singularize}.#{column_name}")
        change_column_comment(
          table_name,
          column_name,
          nil,
        )
      end
    end
  end

  private

    def table_with_columns
      system_view_names = %w(
        pg_stat_statements
        geography_columns
        geometry_columns
        raster_columns
        raster_overviews
      )
      tables = ApplicationRecord.connection.tables
      views = ApplicationRecord.connection.views - system_view_names
      (tables + views).each_with_object({}) { |table, hash| hash[table] = ApplicationRecord.connection.columns(table) }
    end
end