症状

device_token_authを使って認証機能を実装しようとしたところ、以下が表示されました。

翻訳すると、「nil:NilClass の未定義メソッド」でした。

error

 NoMethodError (undefined method `downcase' for nil:NilClass):
rack (2.2.4) lib/rack/utils.rb:464:in `[]='
rack (2.2.4) lib/rack/utils.rb:432:in `block in initialize'
rack (2.2.4) lib/rack/utils.rb:432:in `each'
rack (2.2.4) lib/rack/utils.rb:432:in `initialize'
rack (2.2.4) lib/rack/utils.rb:425:in `new'
rack (2.2.4) lib/rack/utils.rb:425:in `[]'
rack (2.2.4) lib/rack/etag.rb:29:in `call'
rack (2.2.4) lib/rack/conditional_get.rb:40:in `call'
rack (2.2.4) lib/rack/head.rb:12:in `call'
activerecord (6.0.6) lib/active_record/migration.rb:567:in `call'
actionpack (6.0.6) lib/action_dispatch/middleware/callbacks.rb:27:in `block in call'
activesupport (6.0.6) lib/active_support/callbacks.rb:101:in `run_callbacks'
actionpack (6.0.6) lib/action_dispatch/middleware/callbacks.rb:26:in `call'
actionpack (6.0.6) lib/action_dispatch/middleware/executor.rb:14:in `call'
actionpack (6.0.6) lib/action_dispatch/middleware/actionable_exceptions.rb:18:in `call'
actionpack (6.0.6) lib/action_dispatch/middleware/debug_exceptions.rb:32:in `call'
actionpack (6.0.6) lib/action_dispatch/middleware/show_exceptions.rb:33:in `call'
railties (6.0.6) lib/rails/rack/logger.rb:37:in `call_app'
railties (6.0.6) lib/rails/rack/logger.rb:26:in `block in call'
activesupport (6.0.6) lib/active_support/tagged_logging.rb:80:in `block in tagged'
activesupport (6.0.6) lib/active_support/tagged_logging.rb:28:in `tagged'
activesupport (6.0.6) lib/active_support/tagged_logging.rb:80:in `tagged'
railties (6.0.6) lib/rails/rack/logger.rb:26:in `call'
actionpack (6.0.6) lib/action_dispatch/middleware/remote_ip.rb:81:in `call'
actionpack (6.0.6) lib/action_dispatch/middleware/request_id.rb:27:in `call'
rack (2.2.4) lib/rack/runtime.rb:22:in `call'
activesupport (6.0.6) lib/active_support/cache/strategy/local_cache_middleware.rb:29:in `call'
actionpack (6.0.6) lib/action_dispatch/middleware/executor.rb:14:in `call'
actionpack (6.0.6) lib/action_dispatch/middleware/static.rb:126:in `call'
rack (2.2.4) lib/rack/sendfile.rb:110:in `call'
actionpack (6.0.6) lib/action_dispatch/middleware/host_authorization.rb:103:in `call'
rack-cors (1.1.1) lib/rack/cors.rb:100:in `call'
railties (6.0.6) lib/rails/engine.rb:527:in `call'
puma (4.3.12) lib/puma/configuration.rb:228:in `call'
puma (4.3.12) lib/puma/server.rb:727:in `handle_request'
puma (4.3.12) lib/puma/server.rb:476:in `process_client'
puma (4.3.12) lib/puma/server.rb:332:in `block in run'
puma (4.3.12) lib/puma/thread_pool.rb:134:in `block in spawn_thread'

解決方法

authorizationを追加したら、動作するようになりました。

device_token_auth.rb

  config.headers_names = {:'access-token' => 'access-token',
                         :'client' => 'client',
                         :'expiry' => 'expiry',
                         :'uid' => 'uid',
                         :'token-type' => 'token-type',
                         :'authorization' => 'authorization' 
                        }

参考