対象

MySQL と ActsAsTaggableOn を使っている方。

Postgresqlを使っている人はこっちで解決できるかも

要約

config/initializers/acts_as_taggable_on.rb の

ActsAsTaggableOn.force_binary_collation = true

をコメントアウトするとエラーが起きなくなる。

何をして起こったか

いつもは reset しているが
ある動作確認のために
開発環境で bin/rails db:drop を実行して
その後 bin/rails db:create した際に起きた


$ bin/rails db:create

rails aborted!
ActiveRecord::NoDatabaseError: Unknown database 'hogehoge_development'

解決

本題
原因を調べてもわからず、StackTraceをもう一度読んでみると acts-as-taggable-on が異質な感じ。

rails aborted!
ActiveRecord::NoDatabaseError: Unknown database 'hogehoge_development'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activerecord-5.2.2.1/lib/active_record/connection_adapters/mysql2_adapter.rb:26:in `rescue in mysql2_connection'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activerecord-5.2.2.1/lib/active_record/connection_adapters/mysql2_adapter.rb:12:in `mysql2_connection'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activerecord-5.2.2.1/lib/active_record/connection_adapters/abstract/connection_pool.rb:811:in `new_connection'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activerecord-5.2.2.1/lib/active_record/connection_adapters/abstract/connection_pool.rb:855:in `checkout_new_connection'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activerecord-5.2.2.1/lib/active_record/connection_adapters/abstract/connection_pool.rb:834:in `try_to_checkout_new_connection'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activerecord-5.2.2.1/lib/active_record/connection_adapters/abstract/connection_pool.rb:795:in `acquire_connection'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activerecord-5.2.2.1/lib/active_record/connection_adapters/abstract/connection_pool.rb:523:in `checkout'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activerecord-5.2.2.1/lib/active_record/connection_adapters/abstract/connection_pool.rb:382:in `connection'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activerecord-5.2.2.1/lib/active_record/connection_adapters/abstract/connection_pool.rb:1010:in `retrieve_connection'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activerecord-5.2.2.1/lib/active_record/connection_handling.rb:118:in `retrieve_connection'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activerecord-5.2.2.1/lib/active_record/connection_handling.rb:90:in `connection'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/acts-as-taggable-on-6.0.0/lib/acts_as_taggable_on/utils.rb:8:in `connection'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/acts-as-taggable-on-6.0.0/lib/acts_as_taggable_on/utils.rb:16:in `using_mysql?'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/acts-as-taggable-on-6.0.0/lib/acts-as-taggable-on.rb:94:in `force_binary_collation='
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/acts-as-taggable-on-6.0.0/lib/acts-as-taggable-on.rb:50:in `method_missing'
/Users/username/projects/hogehoge/config/initializers/acts_as_taggable_on.rb:1:in `<main>'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:50:in `load'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:50:in `load'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activesupport-5.2.2.1/lib/active_support/dependencies.rb:285:in `block in load'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activesupport-5.2.2.1/lib/active_support/dependencies.rb:257:in `load_dependency'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activesupport-5.2.2.1/lib/active_support/dependencies.rb:285:in `load'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/engine.rb:657:in `block in load_config_initializer'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activesupport-5.2.2.1/lib/active_support/notifications.rb:170:in `instrument'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/engine.rb:656:in `load_config_initializer'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/engine.rb:614:in `block (2 levels) in <class:Engine>'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/engine.rb:613:in `each'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/engine.rb:613:in `block in <class:Engine>'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/initializable.rb:32:in `instance_exec'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/initializable.rb:32:in `run'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/initializable.rb:61:in `block in run_initializers'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/initializable.rb:50:in `each'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/initializable.rb:50:in `tsort_each_child'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/initializable.rb:60:in `run_initializers'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/application.rb:361:in `initialize!'
/Users/username/projects/hogehoge/config/environment.rb:5:in `<main>'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:21:in `require'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:21:in `block in require_with_bootsnap_lfi'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/loaded_features_index.rb:83:in `register'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:20:in `require_with_bootsnap_lfi'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:29:in `require'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activesupport-5.2.2.1/lib/active_support/dependencies.rb:291:in `block in require'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activesupport-5.2.2.1/lib/active_support/dependencies.rb:257:in `load_dependency'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activesupport-5.2.2.1/lib/active_support/dependencies.rb:291:in `require'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/application.rb:337:in `require_environment!'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/application.rb:520:in `block in run_tasks_blocks'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/commands/rake/rake_command.rb:23:in `block in perform'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/commands/rake/rake_command.rb:20:in `perform'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/command.rb:48:in `invoke'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/commands.rb:18:in `<main>'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:21:in `require'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:21:in `block in require_with_bootsnap_lfi'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/loaded_features_index.rb:83:in `register'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:20:in `require_with_bootsnap_lfi'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:29:in `require'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activesupport-5.2.2.1/lib/active_support/dependencies.rb:291:in `block in require'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activesupport-5.2.2.1/lib/active_support/dependencies.rb:257:in `load_dependency'
/Users/username/projects/hogehoge/vendor/bundle/ruby/2.5.0/gems/activesupport-5.2.2.1/lib/active_support/dependencies.rb:291:in `require'
bin/rails:4:in `<main>'

project内でconfig/initializers/acts_as_taggable_on.rb に

ActsAsTaggableOn.force_binary_collation = true

こんな定義があった

公式をみるとMySQLユーザーに対して推奨している設定みたい。ざっくりとしか読んでないけど特殊文字対策と書いてある。
https://github.com/mbleigh/acts-as-taggable-on#for-mysql-users

試しにコメントアウトし
もう一度 bin/rails db:create を実行したところ成功した。

実装をみてみると using_mysql? のところで mysql に connectionしていてここで起きているのかな。
acts-as-taggable-on.rb


    def force_binary_collation=(force_bin)
      if Utils.using_mysql?
        if force_bin
          Configuration.apply_binary_collation(true)
          @force_binary_collation = true
          @strict_case_match = true
        else
          Configuration.apply_binary_collation(false)
          @force_binary_collation = false
        end
      end
    end

StackTraceをさらに読み進めるとここでエラーになってます。

active_record/connection_adapters/mysql2_adapter.rb


    def mysql2_connection(config)
      config = config.symbolize_keys
      config[:flags] ||= 0

      if config[:flags].kind_of? Array
        config[:flags].push "FOUND_ROWS".freeze
      else
        config[:flags] |= Mysql2::Client::FOUND_ROWS
      end

      client = Mysql2::Client.new(config)
      ConnectionAdapters::Mysql2Adapter.new(client, logger, nil, config)
    rescue Mysql2::Error => error
      if error.message.include?("Unknown database")
        raise ActiveRecord::NoDatabaseError
      else
        raise
      end
    end

調べてみると他の人もエラーになっているようだった。

教訓

エラーはStackTrace含めてちゃんと読もう。

時間があるときにもう少しちゃんと読んで解決策考えられると良いかな。
まぁ割と早めに気づけてよかったです。