Rails5でuft8mb4対応

いい感じにまとまってるページがなかったのでまとめておきます。

Mysql(MariaDB）の対応

[mysqld]
character-set-server=utf8mb4
collation-server=utf8mb4_general_ci

innodb_file_format = Barracuda
innodb_file_per_table = 1
innodb_large_prefix

Railsの対応

• config/initializeに追加

# config/initializers/ar_innodb_row_format.rb

ActiveSupport.on_load :active_record do
  module ActiveRecord::ConnectionAdapters
    module CreateTableWithInnodbRowFormat
      def create_table(table_name, options = {})
        table_options = options.merge(options: 'ENGINE=InnoDB ROW_FORMAT=DYNAMIC')
        super(table_name, table_options) do |td|
          yield td if block_given?
        end
      end
    end

    class AbstractMysqlAdapter
      prepend CreateTableWithInnodbRowFormat
    end
  end
end

• database.ymlを修正

# config/database.yml
default: &default
  adapter: mysql2
  encoding: utf8mb4
  charset: utf8mb4
  collation: utf8mb4_general_ci