麻烦通过关联对象创建现有模型的新对象

Question

I'm trying to create a new object via an association as so:

def create
  @enhancement = current_user.enhancements.create enhancement_params

  if @enhancement.save!
    redirect_to enhancements_path, notice: "Mission Control has receieved your request"
  else
    redirect_to enhancements_path, notice: "Danger! Mission Control could not receive your request!"
  end
end

and the error I get is:

wrong number of arguments (1 for 0)

I've also tried

@enhancement = current_user.enhancements.new enhancement_params

and then for your possible reference, here are the strong parameters I'm passing in

def enhancement_params
  params.require(:enhancement).permit(:name, :description, :user_id, :status)
end

Association-wise, the model enhancements belongs_to the user model, and the user model has_many enhancements.

I have no idea what I'm doing wrong and a sneaking suspicion I'm missing something super simple, but I've wasted enough time on this. Any ideas what's going on? Is there any other information I can give you?

Updated -

I'm just doing

 def create
    @enhancement = Enhancement.create enhancement_params
    if @enhancement.save
      redirect_to enhancements_path, notice: "Mission Control has receieved your request"
    else
      redirect_to enhancements_path, notice: "Danger! Mission Control could not receive your request!"
    end
  end

here's the error : wrong number of arguments (1 for 0)

Started POST "/enhancements" for 127.0.0.1 at 2014-03-20 16:29:38 -0500 Processing by EnhancementsController#create as HTML Parameters: {"utf8"=>"✓", "authenticity_token"=>"pKfKnNGB4CWNSBOOKAe/l6Em+MSV5l+tLS0kDRTCQEc=", "enhancement"=>{"name"=>"Wow what enhancemnt ", "description"=>"such enhamcnet \\r\\n\\r\\nvery wow"}, "commit"=>"Save Enhancement"} Completed 500 Internal Server Error in 3ms

ArgumentError - wrong number of arguments (1 for 0):
activerecord-deprecated_finders (1.0.3) lib/active_record/deprecated_finders/base.rb:28:in call'
activerecord (4.0.2) lib/active_record/scoping/named.rb:163:in call'
activerecord (4.0.2) lib/active_record/scoping/named.rb:163:in call'
activerecord (4.0.2) lib/active_record/scoping/named.rb:163:in block (2 levels) in scope' activerecord (4.0.2) lib/active_record/relation.rb:270:in scoping' activerecord (4.0.2) lib/active_record/scoping/named.rb:163:in block in scope'
activerecord (4.0.2) lib/active_record/persistence.rb:36:in create'
app/controllers/enhancements_controller.rb:12:in create'
app/controllers/enhancements_controller.rb:12:in create'
app/controllers/enhancements_controller.rb:12:in create' actionpack (4.0.2) lib/action_controller/metal/implicit_render.rb:4:in send_action' actionpack (4.0.2) lib/abstract_controller/base.rb:189:in process_action' actionpack (4.0.2) lib/action_controller/metal/rendering.rb:10:in process_action' actionpack (4.0.2) lib/abstract_controller/callbacks.rb:18:in block in process_action'
activesupport (4.0.2) lib/active_support/callbacks.rb:403:in _run__3594477325221698156__process_action__callbacks' activesupport (4.0.2) lib/active_support/callbacks.rb:80:in run_callbacks'
actionpack (4.0.2) lib/abstract_controller/callbacks.rb:17:in process_action' actionpack (4.0.2) lib/action_controller/metal/rescue.rb:29:in process_action'
actionpack (4.0.2) lib/action_controller/metal/instrumentation.rb:31:in block in process_action' activesupport (4.0.2) lib/active_support/notifications.rb:159:in block in instrument'
activesupport (4.0.2) lib/active_support/notifications/instrumenter.rb:20:in instrument'
activesupport (4.0.2) lib/active_support/notifications.rb:159:in instrument'
activesupport (4.0.2) lib/active_support/notifications.rb:159:in instrument'
activesupport (4.0.2) lib/active_support/notifications.rb:159:in instrument' actionpack (4.0.2) lib/action_controller/metal/instrumentation.rb:30:in process_action' actionpack (4.0.2) lib/action_controller/metal/params_wrapper.rb:245:in process_action' activerecord (4.0.2) lib/active_record/railties/controller_runtime.rb:18:in process_action' actionpack (4.0.2) lib/abstract_controller/base.rb:136:in process' actionpack (4.0.2) lib/abstract_controller/rendering.rb:44:in process' actionpack (4.0.2) lib/action_controller/metal.rb:195:in dispatch' actionpack (4.0.2) lib/action_controller/metal/rack_delegation.rb:13:in dispatch' actionpack (4.0.2) lib/action_controller/metal.rb:231:in block in action' actionpack (4.0.2) lib/action_dispatch/routing/route_set.rb:80:in dispatch' actionpack (4.0.2) lib/action_dispatch/routing/route_set.rb:48:in call'
actionpack (4.0.2) lib/action_dispatch/journey/router.rb:71:in block in call' actionpack (4.0.2) lib/action_dispatch/journey/router.rb:59:in call' actionpack (4.0.2) lib/action_dispatch/routing/route_set.rb:680:in call'
warden (1.2.3) lib/warden/manager.rb:35:in call'
warden (1.2.3) lib/warden/manager.rb:35: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 (4.0.2) lib/action_dispatch/middleware/params_parser.rb:27:in call'
actionpack (4.0.2) lib/action_dispatch/middleware/flash.rb:241:in call'
actionpack (4.0.2) lib/action_dispatch/middleware/flash.rb:241:in call'
actionpack (4.0.2) 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 (4.0.2) lib/action_dispatch/middleware/cookies.rb:486:in call' activerecord (4.0.2) lib/active_record/query_cache.rb:36:in call' activerecord (4.0.2) lib/active_record/connection_adapters/abstract/connection_pool.rb:626:in call' activerecord (4.0.2) lib/active_record/migration.rb:369:in call' actionpack (4.0.2) lib/action_dispatch/middleware/callbacks.rb:29:in block in call'
activesupport (4.0.2) lib/active_support/callbacks.rb:373:in block in call'
activesupport (4.0.2) lib/active_support/callbacks.rb:373:in block in call'
activesupport (4.0.2) lib/active_support/callbacks.rb:373:in _run__4163598129264950275__call__callbacks' activesupport (4.0.2) lib/active_support/callbacks.rb:80:in run_callbacks' actionpack (4.0.2) lib/action_dispatch/middleware/callbacks.rb:27:in call'
actionpack (4.0.2) lib/action_dispatch/middleware/reloader.rb:64:in call' actionpack (4.0.2) 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 (4.0.2) lib/action_dispatch/middleware/debug_exceptions.rb:17:in call'
actionpack (4.0.2) lib/action_dispatch/middleware/debug_exceptions.rb:17:in call'
actionpack (4.0.2) lib/action_dispatch/middleware/debug_exceptions.rb:17:in call'
actionpack (4.0.2) lib/action_dispatch/middleware/show_exceptions.rb:30:in call'
railties (4.0.2) lib/rails/rack/logger.rb:38:in call'
railties (4.0.2) lib/rails/rack/logger.rb:38:in call'
railties (4.0.2) lib/rails/rack/logger.rb:38:in call_app' railties (4.0.2) lib/rails/rack/logger.rb:20:in block in call' activesupport (4.0.2) lib/active_support/tagged_logging.rb:67:in block in tagged'
activesupport (4.0.2) lib/active_support/tagged_logging.rb:25:in tagged' activesupport (4.0.2) lib/active_support/tagged_logging.rb:67:in tagged' railties (4.0.2) lib/rails/rack/logger.rb:20:in call' actionpack (4.0.2) 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 (4.0.2) lib/active_support/cache/strategy/local_cache.rb:83:in call' rack (1.5.2) lib/rack/lock.rb:17:in call' actionpack (4.0.2) lib/action_dispatch/middleware/static.rb:64:in call' rack (1.5.2) lib/rack/sendfile.rb:112:in call' railties (4.0.2) lib/rails/engine.rb:511:in call' railties (4.0.2) 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/chris/.rbenv/versions/2.0.0-p353/lib/ruby/2.0.0/webrick/httpserver.rb:138:in service'
/Users/chris/.rbenv/versions/2.0.0-p353/lib/ruby/2.0.0/webrick/httpserver.rb:138:in service'
/Users/chris/.rbenv/versions/2.0.0-p353/lib/ruby/2.0.0/webrick/httpserver.rb:138:in service'
/Users/chris/.rbenv/versions/2.0.0-p353/lib/ruby/2.0.0/webrick/httpserver.rb:94:in run'
/Users/chris/.rbenv/versions/2.0.0-p353/lib/ruby/2.0.0/webrick/server.rb:295:in run'
/Users/chris/.rbenv/versions/2.0.0-p353/lib/ruby/2.0.0/webrick/server.rb:295:in run'
/Users/chris/.rbenv/versions/2.0.0-p353/lib/ruby/2.0.0/webrick/server.rb:295:in block in start_thread' `

Answer 1

Try with:

def create
  @enhancement = current_user.enhancements.build enhancement_params

  if @enhancement.save # without bang method, it throws an exception
    redirect_to enhancements_path, notice: "Mission Control has receieved your request"
  else
    redirect_to enhancements_path, notice: "Danger! Mission Control could not receive your request!"
  end
end

I can't imagine which method throws the error in that action, so you should check if any before_filter (or before_action in Rails 4 ) is causing the error.