我使用Factual API和其他API。我想对所有内容使用注释（多态关联） - 对于使用Factual API的栏和其他API的其他内容。
class CommentsController < ApplicationController
before_filter :load_commentable
...
def load_commentable
resource, id = request.path.split('/')[1, 2]
@commentable = resource.singularize.classify.constantize.find(id) <-----
end
创建评论的表格
<%= link_to "New Comment", [:new, @commentable, :comment] %>
bars_controller
def show
query = @factual.table('places')
@bar = query.filters('factual_id' => params[:id]).first
@commentable = @bar
@comments = @commentable.comments
@comment = Comment.new
end
酒吧模特
class Bar < ActiveRecord::Base;
has_many :comments, as: :commentable
end
我使用了this教程。此外，当我有普通的文章模型（在应用程序中创建）时，它的工作完全正常。当使用API时，当我得到错误时就是这样。
服务器日志
Started GET "/bars/472028cb-ded6-489b-94b1-21fd3ec9d35c/comments/new" for 92.241.140.218 at 2014-04-05 20:13:00 +0000
Processing by CommentsController#new as HTML
Parameters: {"bar_id"=>"472028cb-ded6-489b-94b1-21fd3ec9d35c"}
User Load (0.3ms) SELECT "users".* FROM "users" WHERE "users"."id" = ? LIMIT 1 [["id", 1]]
Bar Load (0.2ms) SELECT "bars".* FROM "bars" WHERE "bars"."id" = ? LIMIT 1 [["id", "472028cb-ded6-489b-94b1-21fd3ec9d35c"]]
Completed 404 Not Found in 52ms
ActiveRecord::RecordNotFound - Couldn't find Bar with id=472028cb-ded6-489b-94b1-21fd3ec9d35c:
activerecord (4.0.0) lib/active_record/relation/finder_methods.rb:198:in `raise_record_not_found_exception!'
activerecord (4.0.0) lib/active_record/relation/finder_methods.rb:284:in `find_one'
activerecord (4.0.0) lib/active_record/relation/finder_methods.rb:268:in `find_with_ids'
activerecord (4.0.0) lib/active_record/relation/finder_methods.rb:35:in `find'
activerecord-deprecated_finders (1.0.3) lib/active_record/deprecated_finders/relation.rb:122:in `find'
activerecord (4.0.0) lib/active_record/querying.rb:3:in `find'
app/controllers/comments_controller.rb:67:in `load_commentable'
activesupport (4.0.0) lib/active_support/callbacks.rb:447:in `_run__1736236977553759703__process_action__callbacks'
activesupport (4.0.0) lib/active_support/callbacks.rb:80:in `run_callbacks'
actionpack (4.0.0) lib/abstract_controller/callbacks.rb:17:in `process_action'
actionpack (4.0.0) lib/action_controller/metal/rescue.rb:29:in `process_action'
actionpack (4.0.0) lib/action_controller/metal/instrumentation.rb:31:in `block in process_action'
activesupport (4.0.0) lib/active_support/notifications.rb:159:in `block in instrument'
activesupport (4.0.0) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (4.0.0) lib/active_support/notifications.rb:159:in `instrument'
actionpack (4.0.0) lib/action_controller/metal/instrumentation.rb:30:in `process_action'
actionpack (4.0.0) lib/action_controller/metal/params_wrapper.rb:245:in `process_action'
activerecord (4.0.0) lib/active_record/railties/controller_runtime.rb:18:in `process_action'
actionpack (4.0.0) lib/abstract_controller/base.rb:136:in `process'
actionpack (4.0.0) lib/abstract_controller/rendering.rb:44:in `process'
actionpack (4.0.0) lib/action_controller/metal.rb:195:in `dispatch'
actionpack (4.0.0) lib/action_controller/metal/rack_delegation.rb:13:in `dispatch'
actionpack (4.0.0) lib/action_controller/metal.rb:231:in `block in action'
actionpack (4.0.0) lib/action_dispatch/routing/route_set.rb:80:in `dispatch'
actionpack (4.0.0) lib/action_dispatch/routing/route_set.rb:48:in `call'
actionpack (4.0.0) lib/action_dispatch/journey/router.rb:71:in `block in call'
actionpack (4.0.0) lib/action_dispatch/journey/router.rb:59:in `call'
actionpack (4.0.0) lib/action_dispatch/routing/route_set.rb:655:in `call'
omniauth (1.2.1) lib/omniauth/strategy.rb:186:in `call!'
omniauth (1.2.1) lib/omniauth/strategy.rb:164:in `call'
omniauth (1.2.1) lib/omniauth/builder.rb:59:in `call'
meta_request (0.2.8) lib/meta_request/middlewares/app_request_handler.rb:13:in `call'
rack-contrib (1.1.0) lib/rack/contrib/response_headers.rb:17:in `call'
meta_request (0.2.8) lib/meta_request/middlewares/headers.rb:16:in `call'
meta_request (0.2.8) lib/meta_request/middlewares/meta_request_handler.rb:13:in `call'
newrelic_rpm (3.7.3.204) lib/new_relic/rack/error_collector.rb:55:in `call'
newrelic_rpm (3.7.3.204) lib/new_relic/rack/agent_hooks.rb:32:in `call'
newrelic_rpm (3.7.3.204) lib/new_relic/rack/browser_monitoring.rb:27:in `call'
rack (1.5.2) lib/rack/etag.rb:23:in `call'
rack (1.5.2) lib/rack/conditionalget.rb:25:in `call'
rack (1.5.2) lib/rack/head.rb:11:in `call'
actionpack (4.0.0) lib/action_dispatch/middleware/params_parser.rb:27:in `call'
actionpack (4.0.0) lib/action_dispatch/middleware/flash.rb:241:in `call'
rack (1.5.2) lib/rack/session/abstract/id.rb:225:in `context'
rack (1.5.2) lib/rack/session/abstract/id.rb:220:in `call'
actionpack (4.0.0) lib/action_dispatch/middleware/cookies.rb:486:in `call'
activerecord (4.0.0) lib/active_record/query_cache.rb:36:in `call'
activerecord (4.0.0) lib/active_record/connection_adapters/abstract/connection_pool.rb:626:in `call'
activerecord (4.0.0) lib/active_record/migration.rb:369:in `call'
actionpack (4.0.0) lib/action_dispatch/middleware/callbacks.rb:29:in `block in call'
activesupport (4.0.0) lib/active_support/callbacks.rb:373:in `_run__3544743962306853787__call__callbacks'
activesupport (4.0.0) lib/active_support/callbacks.rb:80:in `run_callbacks'
actionpack (4.0.0) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
actionpack (4.0.0) lib/action_dispatch/middleware/reloader.rb:64:in `call'
actionpack (4.0.0) lib/action_dispatch/middleware/remote_ip.rb:76:in `call'
better_errors (1.1.0) lib/better_errors/middleware.rb:84:in `protected_app_call'
better_errors (1.1.0) lib/better_errors/middleware.rb:79:in `better_errors_call'
better_errors (1.1.0) lib/better_errors/middleware.rb:56:in `call'
actionpack (4.0.0) lib/action_dispatch/middleware/debug_exceptions.rb:17:in `call'
actionpack (4.0.0) lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'
railties (4.0.0) lib/rails/rack/logger.rb:38:in `call_app'
railties (4.0.0) lib/rails/rack/logger.rb:21:in `block in call'
activesupport (4.0.0) lib/active_support/tagged_logging.rb:67:in `block in tagged'
activesupport (4.0.0) lib/active_support/tagged_logging.rb:25:in `tagged'
activesupport (4.0.0) lib/active_support/tagged_logging.rb:67:in `tagged'
railties (4.0.0) lib/rails/rack/logger.rb:21:in `call'
actionpack (4.0.0) lib/action_dispatch/middleware/request_id.rb:21:in `call'
rack (1.5.2) lib/rack/methodoverride.rb:21:in `call'
rack (1.5.2) lib/rack/runtime.rb:17:in `call'
activesupport (4.0.0) lib/active_support/cache/strategy/local_cache.rb:83:in `call'
rack (1.5.2) lib/rack/lock.rb:17:in `call'
actionpack (4.0.0) lib/action_dispatch/middleware/static.rb:64:in `call'
railties (4.0.0) lib/rails/engine.rb:511:in `call'
railties (4.0.0) lib/rails/application.rb:97:in `call'
rack (1.5.2) lib/rack/lock.rb:17:in `call'
rack (1.5.2) lib/rack/content_length.rb:14:in `call'
rack (1.5.2) lib/rack/handler/webrick.rb:60:in `service'
/home/action/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/webrick/httpserver.rb:138:in `service'
/home/action/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/webrick/httpserver.rb:94:in `run'
/home/action/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/webrick/server.rb:295:in `block in start_thread'
模式
create_table "comments", force: true do |t|
t.string "title"
t.text "content"
t.integer "user_id"
t.integer "commentable_id"
t.string "commentable_type"
t.datetime "created_at"
t.datetime "updated_at"
end
create_table "bars", force: true do |t|
t.integer "factual_id"
t.datetime "created_at"
t.datetime "updated_at"
end
答案 0 :(得分：1)
将 load_commentable 替换为：
def load_commentable
resource, id = request.path.split('/')[1, 2]
resource_name = resource.singularize.classify
if resource_name == "Bar"
@factual = Factual.new("...", "...") ## Add your keys
@factual.table('places').query.filters('factual_id' => id).first
else
@commentable = resource_name.constantize.find(id)
end
end
此外，根据聊天会话，factual_id需要存储在Bar模型中：
## BarsController
def show
query = @factual.table('places')
@bar = query.filters('factual_id' => params[:id]).first
@commentable = Bar.find_by(factual_id: params[:id])
@comments = @commentable.comments
@comment = Comment.new
end