我想在Rails 4.0.0应用程序中使用Paperclip将视频文件添加到Episode模型中。但是，当我在创建操作（第二行）中调用episode_params时，我收到错误“没有将符号隐式转换为哈希”：
def create
@episode = Episode.new(episode_params)
respond_to do |format|
if @episode.save
format.html { redirect_to @episode, notice: 'Episode was successfully created.' }
format.json { render action: 'show', status: :created, location: @episode }
else
format.html { render action: 'new' }
format.json { render json: @episode.errors, status: :unprocessable_entity }
end
end
端
我的episode_params方法：
def episode_params
params.require(:episode).permit(:name, :number, :description, :tag_list, :video => [:tempfile, :original_filename, :content_type, :headers])
end
和params哈希：
{"utf8"=>"✓", "authenticity_token"=>"VbOJvzWjlXMHOYpYMkwXUfdUxm9OcQx3LTMIJzk5eJQ=", "episode"=>{"name"=>"Test Episode 2", "number"=>"2", "description"=>"Testing Paperclip with video files", "tag_list"=>"test, file, video", "video"=>#<ActionDispatch::Http::UploadedFile:0x007fec361a80e0 @tempfile=#<Tempfile:/var/folders/yt/prn3v4gx3_bcrq8kr6wlfjjw0000gn/T/RackMultipart20130817-15917-1gu47ht>, @original_filename="file.mov", @content_type="video/quicktime", @headers="Content-Disposition: form-data; name=\"episode[video]\"; filename=\"file.mov\"\r\nContent-Type: video/quicktime\r\n">}, "commit"=>"Create Episode", "action"=>"create", "controller"=>"episodes"}
我也尝试过：视频代替：video =＆gt; [等]没有运气。任何想法都将不胜感激。
完全回溯：
TypeError - no implicit conversion of Symbol into Hash:
paperclip (3.5.1) lib/paperclip/attachment.rb:72:in `initialize'
paperclip (3.5.1) lib/paperclip/has_attached_file.rb:46:in `block in define_instance_getter'
paperclip (3.5.1) lib/paperclip/has_attached_file.rb:65:in `block in define_setter'
activerecord (4.0.0) lib/active_record/attribute_assignment.rb:42:in `_assign_attribute'
activerecord (4.0.0) lib/active_record/attribute_assignment.rb:29:in `block in assign_attributes'
activerecord (4.0.0) lib/active_record/attribute_assignment.rb:23:in `assign_attributes'
activerecord (4.0.0) lib/active_record/core.rb:192:in `initialize'
activerecord (4.0.0) lib/active_record/inheritance.rb:27:in `new'
app/controllers/episodes_controller.rb:34:in `create'
actionpack (4.0.0) lib/action_controller/metal/implicit_render.rb:4:in `send_action'
actionpack (4.0.0) lib/abstract_controller/base.rb:189:in `process_action'
actionpack (4.0.0) lib/action_controller/metal/rendering.rb:10:in `process_action'
actionpack (4.0.0) lib/abstract_controller/callbacks.rb:18:in `block in process_action'
activesupport (4.0.0) lib/active_support/callbacks.rb:413:in `_run__3623801457634608219__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'
warden (1.2.3) lib/warden/manager.rb:35:in `block in call'
warden (1.2.3) lib/warden/manager.rb:34:in `call'
rack (1.5.2) lib/rack/etag.rb:23:in `call'
rack (1.5.2) lib/rack/conditionalget.rb:35: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__4451766820120855143__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 (0.9.0) lib/better_errors/middleware.rb:84:in `protected_app_call'
better_errors (0.9.0) lib/better_errors/middleware.rb:79:in `better_errors_call'
better_errors (0.9.0) 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'
/Users/timhusson/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/webrick/httpserver.rb:138:in `service'
/Users/timhusson/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/webrick/httpserver.rb:94:in `run'
/Users/timhusson/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/webrick/server.rb:295:in `block in start_thread'
答案 0 :(得分：1)
至于你的strong_params问题，你应该只列出回形针附件的名称。假设您的ARec类看起来像这样......
class Episode
has_attached_file :video, ... options ...
end
然后你的参数应该看起来像这样......
def episode_params
params.permit(:episode).permit(:name, :number, :description, :tag_list, :video)
end
如果仔细观察params哈希，你实际上可以理解这一点。 ：视频项是一个对象，上面有一些属性。 Rails strong_params只关心它是一个单个对象并将其视为整数或字符串，因此您只需要允许该属性。我在很多地方都能正常工作。
然而，参数不是你的问题。
如果查看回溯，则错误来自Paperclip :: Attachment #initialize。具体而言，参考线（＃72）表示：
options = self.class.default_options.merge(options)
如果你考虑一下，这在上下文中很有意义。错误告诉您，您无法将符号转换为哈希。很可能这意味着上述语句在“merge（options）”调用中接收到一个Symbol。最终，这可能意味着类定义中的has_attached_file调用格式不正确。
答案 1 :(得分：0)
嗯，您的剧集模型中是否需要“accepts_nested_attributes_for：video”？不确定回形针是否覆盖了。您也可以尝试使用强大的参数：
params.require(:episode).permit(:name, :number, :description, :tag_list, :video_attributes => [:tempfile, :original_filename, :content_type, :headers])
答案 2 :(得分：0)
确保将：default_url值设置为有效路径。我遇到了完全相同的问题，并通过设置有效路径解决了这个问题。