Problem with entity in :using

[amrnt]

Assume I have 2 models: User and Preference. User has_one preference.

And here's Grape entities:

module Entities
  class PreferenceEntity < Grape::Entity
    expose :logo, :background_color
  end

  class UserEntity < Grape::Entity
    expose :full_name
    expose :email
    expose :preference, :as => :preferences, :using => PreferenceEntity
  end
end

Now, with

get "me" do
  present current_user, :with => Entities::UserEntity
end

Throws this error:

{
error: "wrong number of arguments(0 for 2)",
backtrace: [
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/entity.rb:145:in `autoload'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/entity.rb:145:in `value_for'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/entity.rb:124:in `block in serializable_hash'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/entity.rb:123:in `each'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/entity.rb:123:in `inject'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/entity.rb:123:in `serializable_hash'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/activesupport-3.1.1/lib/active_support/json/encoding.rb:55:in `block in as_json'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/activesupport-3.1.1/lib/active_support/json/encoding.rb:78:in `check_for_circular_references'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/activesupport-3.1.1/lib/active_support/json/encoding.rb:54:in `as_json'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/activesupport-3.1.1/lib/active_support/json/encoding.rb:245:in `block in as_json'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/activesupport-3.1.1/lib/active_support/json/encoding.rb:245:in `each'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/activesupport-3.1.1/lib/active_support/json/encoding.rb:245:in `map'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/activesupport-3.1.1/lib/active_support/json/encoding.rb:245:in `as_json'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/activesupport-3.1.1/lib/active_support/json/encoding.rb:47:in `block in encode'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/activesupport-3.1.1/lib/active_support/json/encoding.rb:78:in `check_for_circular_references'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/activesupport-3.1.1/lib/active_support/json/encoding.rb:46:in `encode'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/activesupport-3.1.1/lib/active_support/json/encoding.rb:31:in `encode'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/activesupport-3.1.1/lib/active_support/core_ext/object/to_json.rb:20:in `to_json'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/multi_json-1.0.3/lib/multi_json/engines/json_gem.rb:17:in `encode'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/multi_json-1.0.3/lib/multi_json.rb:72:in `encode'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/middleware/base.rb:115:in `encode_json'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/middleware/formatter.rb:79:in `call'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/middleware/formatter.rb:79:in `block in after'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/middleware/formatter.rb:78:in `collect'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/middleware/formatter.rb:78:in `after'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/middleware/base.rb:26:in `call!'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/middleware/base.rb:19:in `call'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/middleware/base.rb:25:in `call!'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/middleware/base.rb:19:in `call'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/middleware/base.rb:25:in `call!'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/middleware/base.rb:19:in `call'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/middleware/error.rb:44:in `block in call!'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/middleware/error.rb:43:in `catch'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/middleware/error.rb:43:in `call!'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/middleware/base.rb:19:in `call'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/rack-mount-0.8.3/lib/rack/mount/route_set.rb:152:in `block in call'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/rack-mount-0.8.3/lib/rack/mount/code_generation.rb:96:in `block in recognize'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/rack-mount-0.8.3/lib/rack/mount/code_generation.rb:68:in `optimized_each'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/rack-mount-0.8.3/lib/rack/mount/code_generation.rb:95:in `recognize'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/rack-mount-0.8.3/lib/rack/mount/route_set.rb:141:in `call'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bundler/gems/grape-ece183048418/lib/grape/api.rb:32:in `call'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/warden-1.1.0/lib/warden/manager.rb:35:in `block in call'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/warden-1.1.0/lib/warden/manager.rb:34:in `catch'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/warden-1.1.0/lib/warden/manager.rb:34:in `call'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/rack-1.3.5/lib/rack/session/abstract/id.rb:195:in `context'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/rack-1.3.5/lib/rack/session/abstract/id.rb:190:in `call'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/rack-1.3.5/lib/rack/reloader.rb:44:in `call'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/thin-1.3.1/lib/thin/connection.rb:80:in `block in pre_process'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/thin-1.3.1/lib/thin/connection.rb:78:in `catch'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/thin-1.3.1/lib/thin/connection.rb:78:in `pre_process'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/thin-1.3.1/lib/thin/connection.rb:53:in `process'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/thin-1.3.1/lib/thin/connection.rb:38:in `receive_data'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/eventmachine-1.0.0.beta.4/lib/eventmachine.rb:179:in `run_machine'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/eventmachine-1.0.0.beta.4/lib/eventmachine.rb:179:in `run'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/thin-1.3.1/lib/thin/backends/base.rb:61:in `start'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/thin-1.3.1/lib/thin/server.rb:159:in `start'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/thin-1.3.1/lib/thin/controllers/controller.rb:86:in `start'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/thin-1.3.1/lib/thin/runner.rb:185:in `run_command'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/thin-1.3.1/lib/thin/runner.rb:151:in `run!'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/gems/thin-1.3.1/bin/thin:6:in `<top (required)>'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bin/thin:19:in `load'",
"/Users/amr/.rvm/gems/ruby-1.9.2-p290@api-new/bin/thin:19:in `<main>'"
]
}

[amrnt]

I got over this issue by using

expose :preferences do |model, options|
  if model.preference
    # Hash
  end
end

instead of expose :preference, :as => :preferences, :using => PreferenceEntity

But I think its still an issue!

[justfalter]

I believe I've run into this issue, myself. I can't seem to find a way leverage :using in the way that the documentation seems to intend its usage: nesting entities.

Grape::Entity implements #as_json, but when JSON encoders like OkJson go to encode the nested Entity objects, it tries to call #to_json (which does not exist). Depending on the JSON encoder, they may chose to encode an object that lacks #to_json, however OkJson throws an exception if it does not.

I've effectively done the following in my code in order to encode the entities in a consistent manner.

expose :preferences do |model, options|
  if model.preference
    model.preference.map { |pref| PreferenceEntity.new(pref).serializable_hash }
  end
end

Alternatively, doing something like the following also works, but I suspect that it is a bit inappropriate.

class PreferenceEntity < Grape::Entity
   alias :to_json :as_json
   ...
end

I haven't looked into it more deeply, but I may see if I can't figure out a patch and send a pull request to fix it.

[256dpi]

For me the :using property is also not working. I think its because of the missing to_json function or something like that:

[
  {
    ...
    "slots": [
      "#<Harbour::API::V1::SlotEntity:0x007fcb33d243c0>",
      "#<Harbour::API::V1::SlotEntity:0x007fcb33d24230>",
      "#<Harbour::API::V1::SlotEntity:0x007fcb33d240f0>",
      "#<Harbour::API::V1::SlotEntity:0x007fcb33d23fb0>",
      "#<Harbour::API::V1::SlotEntity:0x007fcb33d23dd0>"
    ]
  }
]

To fix the nesting problem i'm using currently the following method:

expose :slots do |station,options|
  station.slots.map{ |slot| SlotEntity.new(slot).serializable_hash }
end

[chrisbloom7]

Similar fix for a has_one relationship:

expose :address do |model, options|
  if model.address
    API::Entities::V1::Location.new(model.address).serializable_hash
  end
end

Trying it the recommended way resulted in the following error:

undefined method `represent' for #<Class:0x00000129261f90>

/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/activerecord-3.2.8/lib/active_record/dynamic_matchers.rb:50:in `method_missing'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/entity.rb:348:in `value_for'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/entity.rb:317:in `block in serializable_hash'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/entity.rb:315:in `each'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/entity.rb:315:in `inject'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/entity.rb:315:in `serializable_hash'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/middleware/base.rb:122:in `serialize'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/middleware/base.rb:134:in `encode_json'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/middleware/formatter.rb:79:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/middleware/formatter.rb:79:in `block in after'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/middleware/formatter.rb:78:in `collect'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/middleware/formatter.rb:78:in `after'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/middleware/base.rb:27:in `call!'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/middleware/base.rb:20:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/middleware/base.rb:26:in `call!'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/middleware/base.rb:20:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/middleware/base.rb:26:in `call!'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/middleware/base.rb:20:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/middleware/error.rb:44:in `block in call!'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/middleware/error.rb:43:in `catch'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/middleware/error.rb:43:in `call!'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/middleware/base.rb:20:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/rack-1.4.1/lib/rack/head.rb:9:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/rack-1.4.1/lib/rack/builder.rb:134:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/endpoint.rb:113:in `call!'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/endpoint.rb:103:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/rack-mount-0.8.3/lib/rack/mount/route_set.rb:152:in `block in call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/rack-mount-0.8.3/lib/rack/mount/code_generation.rb:96:in `block in recognize'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/rack-mount-0.8.3/lib/rack/mount/code_generation.rb:96:in `optimized_each'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/rack-mount-0.8.3/lib/rack/mount/code_generation.rb:95:in `recognize'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/rack-mount-0.8.3/lib/rack/mount/route_set.rb:141:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/api.rb:425:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/api.rb:55:in `call!'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/grape-0.2.2/lib/grape/api.rb:51:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/journey-1.0.4/lib/journey/router.rb:68:in `block in call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/journey-1.0.4/lib/journey/router.rb:56:in `each'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/journey-1.0.4/lib/journey/router.rb:56:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/actionpack-3.2.8/lib/action_dispatch/routing/route_set.rb:600:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/warden-1.2.1/lib/warden/manager.rb:35:in `block in call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/warden-1.2.1/lib/warden/manager.rb:34:in `catch'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/warden-1.2.1/lib/warden/manager.rb:34:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/actionpack-3.2.8/lib/action_dispatch/middleware/best_standards_support.rb:17:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/rack-1.4.1/lib/rack/etag.rb:23:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/rack-1.4.1/lib/rack/conditionalget.rb:25:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/actionpack-3.2.8/lib/action_dispatch/middleware/head.rb:14:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/actionpack-3.2.8/lib/action_dispatch/middleware/params_parser.rb:21:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/actionpack-3.2.8/lib/action_dispatch/middleware/flash.rb:242:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/rack-1.4.1/lib/rack/session/abstract/id.rb:205:in `context'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/rack-1.4.1/lib/rack/session/abstract/id.rb:200:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/actionpack-3.2.8/lib/action_dispatch/middleware/cookies.rb:339:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/activerecord-3.2.8/lib/active_record/query_cache.rb:64:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/activerecord-3.2.8/lib/active_record/connection_adapters/abstract/connection_pool.rb:473:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/actionpack-3.2.8/lib/action_dispatch/middleware/callbacks.rb:28:in `block in call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/activesupport-3.2.8/lib/active_support/callbacks.rb:405:in `_run__644697953361164916__call__1047081581030344329__callbacks'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/activesupport-3.2.8/lib/active_support/callbacks.rb:405:in `__run_callback'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/activesupport-3.2.8/lib/active_support/callbacks.rb:385:in `_run_call_callbacks'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/activesupport-3.2.8/lib/active_support/callbacks.rb:81:in `run_callbacks'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/actionpack-3.2.8/lib/action_dispatch/middleware/callbacks.rb:27:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/actionpack-3.2.8/lib/action_dispatch/middleware/reloader.rb:65:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/actionpack-3.2.8/lib/action_dispatch/middleware/remote_ip.rb:31:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/actionpack-3.2.8/lib/action_dispatch/middleware/debug_exceptions.rb:16:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/actionpack-3.2.8/lib/action_dispatch/middleware/show_exceptions.rb:56:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.8/lib/rails/rack/logger.rb:26:in `call_app'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.8/lib/rails/rack/logger.rb:16:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/actionpack-3.2.8/lib/action_dispatch/middleware/request_id.rb:22:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/rack-1.4.1/lib/rack/methodoverride.rb:21:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/rack-1.4.1/lib/rack/runtime.rb:17:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/activesupport-3.2.8/lib/active_support/cache/strategy/local_cache.rb:72:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/rack-1.4.1/lib/rack/lock.rb:15:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/actionpack-3.2.8/lib/action_dispatch/middleware/static.rb:62:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.8/lib/rails/engine.rb:479:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.8/lib/rails/application.rb:223:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/rack-1.4.1/lib/rack/content_length.rb:14:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.8/lib/rails/rack/log_tailer.rb:17:in `call'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/thin-1.5.0/lib/thin/connection.rb:81:in `block in pre_process'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/thin-1.5.0/lib/thin/connection.rb:79:in `catch'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/thin-1.5.0/lib/thin/connection.rb:79:in `pre_process'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/thin-1.5.0/lib/thin/connection.rb:54:in `process'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/thin-1.5.0/lib/thin/connection.rb:39:in `receive_data'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/eventmachine-1.0.0/lib/eventmachine.rb:187:in `run_machine'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/eventmachine-1.0.0/lib/eventmachine.rb:187:in `run'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/thin-1.5.0/lib/thin/backends/base.rb:63:in `start'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/thin-1.5.0/lib/thin/server.rb:159:in `start'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/rack-1.4.1/lib/rack/handler/thin.rb:13:in `run'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/rack-1.4.1/lib/rack/server.rb:265:in `start'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.8/lib/rails/commands/server.rb:70:in `start'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.8/lib/rails/commands.rb:55:in `block in <top (required)>'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.8/lib/rails/commands.rb:50:in `tap'
/Users/chrisbloom7/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.8/lib/rails/commands.rb:50:in `<top (required)>'
script/rails:6:in `require'
script/rails:6:in `<main>'

[lucassus]

I have the same issue. The strangest thing is that it works on my laptop but breaks on travis-ci (https://travis-ci.org/lucassus/mongo_browser/jobs/3839962) and on my other machine.
Here is code for my API: https://github.com/lucassus/mongo_browser/blob/master/lib/mongo_browser/api.rb
And here is my workaround for the problem: lucassus/mongo_browser@47de199

On both machines I have the same ruby's configuration: ruby-1.9.3-p327-perf with separate rvm gemsets for my project.

[dblock]

This may be fixed on HEAD. We now fully reply on the formatter, so if you use format :json it will call to_json where possible. I'd appreciate if those on this thread could try again and see if there're still problems.

[dblock]

@agileanimal Does this bug belong in grape-entity?

[idyll]

What's the best way to move it over and keep the thread?

[mtjhax]

I was not able to reproduce the original error from @amrnt in Rails 3.2.11 and Grape 0.2.6. I notice the original error backtrace referenced Rails 3.1.1 and Grape 0.2.2. Unclear if I am attempting to reproduce the problem improperly or it was fixed per @dblock.

[dblock]

@amrnt Do you have any updates to this? Is it a problem still? Can I close this?

[dblock]

I am closing this.