NoMethodError and caching

[JWesorick]

I'm getting a NoMethodError when I run all my specs together, however running any single controllers specs pass just fine. What's also weird is the missing method is in a serializer that is not being used in the current context. Finally, if I remove the cache line for each serializer it works just fine. I'm using active_model_serializers (0.10.0.rc4). Here are the relevant bits:

class UserSerializer < ActiveModel::Serializer
  cache key: 'user', expires_in: 12.hour

  attributes :id, :email
  attributes :has_twitter

  def has_twitter
    object.identity?('twitter')
  end
end

class UserPublicSerializer < ActiveModel::Serializer
  cache key: 'user_public', expires_in: 12.hour

  attributes :id, :first_name, :last_name

  def first_name
    object.first_name
  end

  def last_name
    object.last_initial
  end
end

module API
  module V1
    class PartnersController < APIController
      def mayor
        @partner = Partner.find(params[:partner_id])
        @mayor = @partner.competing_users.first
        if @mayor.present?
          render json: @mayor, serializer: UserPublicSerializer
        else
          render json: {}
        end
      end
  end
end

Failure/Error: get :mayor, partner_id: @partner.id
     NoMethodError:
       undefined method `has_twitter' for #<User:0x007fd2456b9aa8>
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activemodel-4.2.4/lib/active_model/attribute_methods.rb:433:in `method_missing'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/rolify-4.0.0/lib/rolify/role.rb:78:in `method_missing'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/acts_as_follower-0.2.1/lib/acts_as_follower/follower.rb:96:in `method_missing'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer.rb:127:in `read_attribute_for_serialization'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer.rb:125:in `read_attribute_for_serialization'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/field.rb:17:in `value'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/attributes.rb:22:in `block in attributes'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/attributes.rb:19:in `each'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/attributes.rb:19:in `each_with_object'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/attributes.rb:19:in `attributes'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/adapter/attributes.rb:60:in `block in resource_object_for'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/adapter/base.rb:33:in `block in cache_check'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/adapter/cached_serializer.rb:18:in `cache_check'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/adapter/base.rb:32:in `cache_check'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/adapter/attributes.rb:59:in `resource_object_for'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/adapter/attributes.rb:31:in `serializable_hash_for_single_resource'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/adapter/attributes.rb:16:in `serializable_hash'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/adapter/fragment_cache.rb:31:in `fetch'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/adapter/cached_serializer.rb:16:in `cache_check'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/adapter/base.rb:32:in `cache_check'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/adapter/attributes.rb:59:in `resource_object_for'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/adapter/attributes.rb:31:in `serializable_hash_for_single_resource'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/adapter/attributes.rb:16:in `serializable_hash'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer/adapter/base.rb:22:in `as_json'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/json/encoding.rb:35:in `encode'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/json/encoding.rb:22:in `encode'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/core_ext/object/json.rb:37:in `to_json_with_active_support_encoder'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializable_resource.rb:7:in `to_json'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model_serializers/logging.rb:69:in `block (3 levels) in notify'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:117:in `call'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:117:in `call'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:555:in `block (2 levels) in compile'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:505:in `call'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:505:in `call'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:498:in `block (2 levels) in around'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:343:in `call'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:343:in `block (2 levels) in simple'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model_serializers/logging.rb:22:in `call'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model_serializers/logging.rb:22:in `block (3 levels) in instrument_rendering'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model_serializers/logging.rb:79:in `block in notify_render'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/notifications.rb:164:in `block in instrument'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/notifications/instrumenter.rb:20:in `instrument'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/notifications.rb:164:in `instrument'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model_serializers/logging.rb:78:in `notify_render'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model_serializers/logging.rb:21:in `block (2 levels) in instrument_rendering'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model_serializers/logging.rb:92:in `block in tag_logger'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/tagged_logging.rb:68:in `block in tagged'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/tagged_logging.rb:26:in `tagged'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/tagged_logging.rb:68:in `tagged'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model_serializers/logging.rb:92:in `tag_logger'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model_serializers/logging.rb:20:in `block in instrument_rendering'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:441:in `instance_exec'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:441:in `block in make_lambda'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:342:in `call'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:342:in `block in simple'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:497:in `call'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:497:in `block in around'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:505:in `call'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:505:in `call'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:92:in `__run_callbacks__'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:778:in `_run_render_callbacks'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:81:in `run_callbacks'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model_serializers/logging.rb:68:in `block (2 levels) in notify'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/action_controller/metal/renderers.rb:116:in `block in <module:Renderers>'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/action_controller/serialization.rb:61:in `block (2 levels) in <module:Serialization>'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/action_controller/metal/renderers.rb:45:in `block in _render_to_body_with_renderer'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/action_controller/metal/renderers.rb:41:in `_render_to_body_with_renderer'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/action_controller/metal/renderers.rb:37:in `render_to_body'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/abstract_controller/rendering.rb:25:in `render'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/action_controller/metal/rendering.rb:16:in `render'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/action_controller/metal/instrumentation.rb:44:in `block (2 levels) in render'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/core_ext/benchmark.rb:12:in `block in ms'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/core_ext/benchmark.rb:12:in `ms'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/action_controller/metal/instrumentation.rb:44:in `block in render'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/action_controller/metal/instrumentation.rb:87:in `cleanup_view_runtime'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activerecord-4.2.4/lib/active_record/railties/controller_runtime.rb:25:in `cleanup_view_runtime'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/action_controller/metal/instrumentation.rb:43:in `render'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/meta-tags-2.0.0/lib/meta_tags/controller_helper.rb:26:in `render_with_meta_tags'
     # ./app/controllers/api/v1/partners_controller.rb:77:in `mayor'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/action_controller/metal/implicit_render.rb:4:in `send_action'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/abstract_controller/base.rb:198:in `process_action'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/action_controller/metal/rendering.rb:10:in `process_action'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/abstract_controller/callbacks.rb:20:in `block in process_action'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:117:in `call'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:117:in `call'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:555:in `block (2 levels) in compile'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:505:in `call'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:505:in `call'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:92:in `__run_callbacks__'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:778:in `_run_process_action_callbacks'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/callbacks.rb:81:in `run_callbacks'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/abstract_controller/callbacks.rb:19:in `process_action'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/action_controller/metal/rescue.rb:29:in `process_action'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/action_controller/metal/instrumentation.rb:32:in `block in process_action'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/notifications.rb:164:in `block in instrument'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/notifications/instrumenter.rb:20:in `instrument'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activesupport-4.2.4/lib/active_support/notifications.rb:164:in `instrument'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/action_controller/metal/instrumentation.rb:30:in `process_action'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/action_controller/metal/params_wrapper.rb:250:in `process_action'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/activerecord-4.2.4/lib/active_record/railties/controller_runtime.rb:18:in `process_action'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/abstract_controller/base.rb:137:in `process'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionview-4.2.4/lib/action_view/rendering.rb:30:in `process'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/action_controller/test_case.rb:637:in `process'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/action_controller/test_case.rb:65:in `process'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/devise-3.5.1/lib/devise/test_helpers.rb:19:in `block in process'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/devise-3.5.1/lib/devise/test_helpers.rb:72:in `catch'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/devise-3.5.1/lib/devise/test_helpers.rb:72:in `_catch_warden'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/devise-3.5.1/lib/devise/test_helpers.rb:19:in `process'
     # /Users/jakewesorick/.rvm/gems/ruby-2.2.3/gems/actionpack-4.2.4/lib/action_controller/test_case.rb:512:in `get'
     # ./spec/controllers/api/v1/partners_controller_spec.rb:221:in `block (3 levels) in <top (required)>'

[bf4]

Thanks for the bug report! It's pretty easy to see where in read_attribute_for_serialization the error is coming from and that it's calling a method on the object that only exists on the serializer. This may be related to or share a fix with #1509

Awesome job sharing the stack trace

    def read_attribute_for_serialization(attr)
      if self.class._serializer_instance_method_defined?(attr)
        send(attr)
      elsif self.class._fragmented
          # .rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer.rb:125:in 
        self.class._fragmented.read_attribute_for_serialization(attr)
      else
        # .rvm/gems/ruby-2.2.3/gems/active_model_serializers-0.10.0.rc4/lib/active_model/serializer.rb:127:in 
        object.read_attribute_for_serialization(attr)
      end
    end

The problem is that

      if self.class._serializer_instance_method_defined?(attr)
        send(attr)

should be calling has_twitter on the serializer, but self.class._serializer_instance_method_defined?(attr) is false for some reason (race condition, dynamic code, etc).

A hotfix would be to use the block form

  attributes :has_twitter do
    object.identity?('twitter')
  end

or modify the read_attribute_for_serialization method... :(

[bf4]

I tagged it as a duplicate since the failure is in the same part of the code, even though it has a different etiology #1509

[JWesorick]

I tried switching to the block form but I'm still seeing the issue. I'm kinda confused though, why is read_attribute_for_serialization even being called for has_twitter when it's not even in the serializer being used?

[bf4]

Maybe I was too quick to interpret the stacktrace. I'll take another look tomorrow, and maybe we can pair or chat in the slack.

B mobile phone

On Feb 13, 2016, at 10:03 AM, Jake Wesorick notifications@github.com wrote:

I tried switching to the block form but I'm still seeing the issue. I'm kinda confused though, why is read_attribute_for_serialization even being called for has_twitter when it's not even in the serializer being used?

—
Reply to this email directly or view it on GitHub.

[JWesorick]

Is this the issue?

https://github.com/rails-api/active_model_serializers/blob/v0.10.0.rc4/lib/active_model/serializer/adapter/fragment_cache.rb#L21

serializers = fragment_serializer(serializer.object.class.name, klass)

This doesn't seem to be taking into account that I have 2 different serializers for the same object.

[bf4]

I wonder if that's fixed for you on master.

[JWesorick]

The same things seems to be happening with the latest from master.

[bf4]

could you provide a sample User class we can use to generate a failing test?

[JWesorick]

Yea, I think just any two serializers for the same object with different attributes and a cache will cause it. I'll try to make a basic app with the issue when I get a chance.

[JWesorick]

Here is an app that has the issue: https://github.com/JWesorick/active_model_serializers_bug
You can run the tests with rake test test/controllers/welcome_controller_test.rb

In this one, the public serializer is being used but is throwing an error undefined method super_secret which is in the private serializer.