"param is missing or the value is empty: user"
"param is missing or the value is empty: user"
我试图在创建 user 的同时创建 book。所以形式 Book 嵌套在 User 中。
但是我无法通过，因为我遇到了这个错误：
param is missing or the value is empty
我查看了人们在 slack 上遇到此错误的每个问题。
但是 none 适合我的情况。
因此，如果您有任何想法，请随时提供帮助。
user.rb
class User < ApplicationRecord
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :trackable, :validatable
has_many :books
has_many :covers, through: :books
has_many :commands
accepts_nested_attributes_for :books
end
book.rb
class Book < ApplicationRecord
has_one :cover
belongs_to :user, dependent: :destroy
end
registrations_controller
class RegistrationsController < Devise::RegistrationsController
def new
build_resource(sign_up_params)
self.resource.books = Book.new
respond_with self.resource
end
def create
super
end
private
def sign_up_params
params.require(resource_name).permit(:email, :password, :password_confirmation, :books_attributes[:title, :author_first_name, :author_last_name])
end
end
我检查了 resource_name，它正好等于 :user
devise/registrations/new
h2
| Sign up
= form_for(resource, as: resource_name, url: registration_path(resource_name)) do |f|
= devise_error_messages!
.field
= f.label :email
br
= f.email_field :email, autofocus: true
.field
= f.label :password
- if @minimum_password_length
em
| (
= @minimum_password_length
| characters minimum)
br
= f.password_field :password, autocomplete: "off"
.field
= f.label :password_confirmation
br
= f.password_field :password_confirmation, autocomplete: "off"
= f.fields_for :books do |p|
= p.text_field :title
= p.text_field :author_first_name
= p.text_field :author_last_name
.actions
= f.submit "Sign up"
= render "devise/shared/links"
编辑
路线
Rails.application.routes.draw do
devise_for :users, controllers: {registrations: 'registrations'}
root 'home#index'
end
log
Started GET "/users/sign_up" for ::1 at 2017-03-10 08:59:00 +0100
Processing by RegistrationsController#new as HTML
Completed 400 Bad Request in 1ms (ActiveRecord: 0.0ms)
ActionController::ParameterMissing - param is missing or the value is empty: user:
actionpack (5.0.2) lib/action_controller/metal/strong_parameters.rb:309:in `require'
app/controllers/registrations_controller.rb:15:in `sign_up_params'
app/controllers/registrations_controller.rb:3:in `new'
actionpack (5.0.2) lib/action_controller/metal/basic_implicit_render.rb:4:in `send_action'
actionpack (5.0.2) lib/abstract_controller/base.rb:188:in `process_action'
actionpack (5.0.2) lib/action_controller/metal/rendering.rb:30:in `process_action'
actionpack (5.0.2) lib/abstract_controller/callbacks.rb:20:in `block in process_action'
activesupport (5.0.2) lib/active_support/callbacks.rb:126:in `call'
activesupport (5.0.2) lib/active_support/callbacks.rb:506:in `block (2 levels) in compile'
activesupport (5.0.2) lib/active_support/callbacks.rb:455:in `call'
activesupport (5.0.2) lib/active_support/callbacks.rb:101:in `__run_callbacks__'
activesupport (5.0.2) lib/active_support/callbacks.rb:750:in `_run_process_action_callbacks'
activesupport (5.0.2) lib/active_support/callbacks.rb:90:in `run_callbacks'
actionpack (5.0.2) lib/abstract_controller/callbacks.rb:19:in `process_action'
actionpack (5.0.2) lib/action_controller/metal/rescue.rb:20:in `process_action'
actionpack (5.0.2) lib/action_controller/metal/instrumentation.rb:32:in `block in process_action'
activesupport (5.0.2) lib/active_support/notifications.rb:164:in `block in instrument'
activesupport (5.0.2) lib/active_support/notifications/instrumenter.rb:21:in `instrument'
activesupport (5.0.2) lib/active_support/notifications.rb:164:in `instrument'
actionpack (5.0.2) lib/action_controller/metal/instrumentation.rb:30:in `process_action'
actionpack (5.0.2) lib/action_controller/metal/params_wrapper.rb:248:in `process_action'
activerecord (5.0.2) lib/active_record/railties/controller_runtime.rb:18:in `process_action'
actionpack (5.0.2) lib/abstract_controller/base.rb:126:in `process'
actionview (5.0.2) lib/action_view/rendering.rb:30:in `process'
actionpack (5.0.2) lib/action_controller/metal.rb:190:in `dispatch'
actionpack (5.0.2) lib/action_controller/metal.rb:262:in `dispatch'
actionpack (5.0.2) lib/action_dispatch/routing/route_set.rb:50:in `dispatch'
actionpack (5.0.2) lib/action_dispatch/routing/route_set.rb:32:in `serve'
actionpack (5.0.2) lib/action_dispatch/routing/mapper.rb:16:in `block in <class:Constraints>'
actionpack (5.0.2) lib/action_dispatch/routing/mapper.rb:46:in `serve'
actionpack (5.0.2) lib/action_dispatch/journey/router.rb:39:in `block in serve'
actionpack (5.0.2) lib/action_dispatch/journey/router.rb:26:in `serve'
actionpack (5.0.2) lib/action_dispatch/routing/route_set.rb:725:in `call'
warden (1.2.7) lib/warden/manager.rb:36:in `block in call'
warden (1.2.7) lib/warden/manager.rb:35:in `call'
rack (2.0.1) lib/rack/etag.rb:25:in `call'
rack (2.0.1) lib/rack/conditional_get.rb:25:in `call'
rack (2.0.1) lib/rack/head.rb:12:in `call'
rack (2.0.1) lib/rack/session/abstract/id.rb:222:in `context'
rack (2.0.1) lib/rack/session/abstract/id.rb:216:in `call'
actionpack (5.0.2) lib/action_dispatch/middleware/cookies.rb:613:in `call'
activerecord (5.0.2) lib/active_record/migration.rb:553:in `call'
actionpack (5.0.2) lib/action_dispatch/middleware/callbacks.rb:38:in `block in call'
activesupport (5.0.2) lib/active_support/callbacks.rb:97:in `__run_callbacks__'
activesupport (5.0.2) lib/active_support/callbacks.rb:750:in `_run_call_callbacks'
activesupport (5.0.2) lib/active_support/callbacks.rb:90:in `run_callbacks'
actionpack (5.0.2) lib/action_dispatch/middleware/callbacks.rb:36:in `call'
actionpack (5.0.2) lib/action_dispatch/middleware/executor.rb:12:in `call'
actionpack (5.0.2) lib/action_dispatch/middleware/remote_ip.rb:79:in `call'
better_errors (2.1.1) lib/better_errors/middleware.rb:84:in `protected_app_call'
better_errors (2.1.1) lib/better_errors/middleware.rb:79:in `better_errors_call'
better_errors (2.1.1) lib/better_errors/middleware.rb:57:in `call'
actionpack (5.0.2) lib/action_dispatch/middleware/debug_exceptions.rb:49:in `call'
web-console (3.4.0) lib/web_console/middleware.rb:135:in `call_app'
web-console (3.4.0) lib/web_console/middleware.rb:28:in `block in call'
web-console (3.4.0) lib/web_console/middleware.rb:18:in `call'
actionpack (5.0.2) lib/action_dispatch/middleware/show_exceptions.rb:31:in `call'
railties (5.0.2) lib/rails/rack/logger.rb:36:in `call_app'
railties (5.0.2) lib/rails/rack/logger.rb:24:in `block in call'
activesupport (5.0.2) lib/active_support/tagged_logging.rb:69:in `block in tagged'
activesupport (5.0.2) lib/active_support/tagged_logging.rb:26:in `tagged'
activesupport (5.0.2) lib/active_support/tagged_logging.rb:69:in `tagged'
railties (5.0.2) lib/rails/rack/logger.rb:24:in `call'
sprockets-rails (3.2.0) lib/sprockets/rails/quiet_assets.rb:13:in `call'
actionpack (5.0.2) lib/action_dispatch/middleware/request_id.rb:24:in `call'
rack (2.0.1) lib/rack/method_override.rb:22:in `call'
rack (2.0.1) lib/rack/runtime.rb:22:in `call'
activesupport (5.0.2) lib/active_support/cache/strategy/local_cache_middleware.rb:28:in `call'
actionpack (5.0.2) lib/action_dispatch/middleware/executor.rb:12:in `call'
actionpack (5.0.2) lib/action_dispatch/middleware/static.rb:136:in `call'
rack (2.0.1) lib/rack/sendfile.rb:111:in `call'
railties (5.0.2) lib/rails/engine.rb:522:in `call'
puma (3.7.1) lib/puma/configuration.rb:232:in `call'
puma (3.7.1) lib/puma/server.rb:578:in `handle_request'
puma (3.7.1) lib/puma/server.rb:415:in `process_client'
puma (3.7.1) lib/puma/server.rb:275:in `block in run'
puma (3.7.1) lib/puma/thread_pool.rb:120:in `block in spawn_thread'
Started POST "/__better_errors/8c394ae550fda307/variables" for ::1 at 2017-03-10 08:59:00 +0100
我终于明白这个错误是从哪里来的了。
调用参数时，只需在 create 操作中调用即可。在 new 操作中调用它们会产生错误。
编辑后的代码：
class RegistrationsController < Devise::RegistrationsController
def new
build_resource
self.resource.books = Book.new
respond_with self.resource
end
......
end
我试图在创建 user 的同时创建 book。所以形式 Book 嵌套在 User 中。
但是我无法通过，因为我遇到了这个错误：
param is missing or the value is empty
我查看了人们在 slack 上遇到此错误的每个问题。
但是 none 适合我的情况。
因此，如果您有任何想法，请随时提供帮助。
user.rb
class User < ApplicationRecord
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :trackable, :validatable
has_many :books
has_many :covers, through: :books
has_many :commands
accepts_nested_attributes_for :books
end
book.rb
class Book < ApplicationRecord
has_one :cover
belongs_to :user, dependent: :destroy
end
registrations_controller
class RegistrationsController < Devise::RegistrationsController
def new
build_resource(sign_up_params)
self.resource.books = Book.new
respond_with self.resource
end
def create
super
end
private
def sign_up_params
params.require(resource_name).permit(:email, :password, :password_confirmation, :books_attributes[:title, :author_first_name, :author_last_name])
end
end
我检查了 resource_name，它正好等于 :user
devise/registrations/new
h2
| Sign up
= form_for(resource, as: resource_name, url: registration_path(resource_name)) do |f|
= devise_error_messages!
.field
= f.label :email
br
= f.email_field :email, autofocus: true
.field
= f.label :password
- if @minimum_password_length
em
| (
= @minimum_password_length
| characters minimum)
br
= f.password_field :password, autocomplete: "off"
.field
= f.label :password_confirmation
br
= f.password_field :password_confirmation, autocomplete: "off"
= f.fields_for :books do |p|
= p.text_field :title
= p.text_field :author_first_name
= p.text_field :author_last_name
.actions
= f.submit "Sign up"
= render "devise/shared/links"
编辑
路线
Rails.application.routes.draw do
devise_for :users, controllers: {registrations: 'registrations'}
root 'home#index'
end
log
Started GET "/users/sign_up" for ::1 at 2017-03-10 08:59:00 +0100
Processing by RegistrationsController#new as HTML
Completed 400 Bad Request in 1ms (ActiveRecord: 0.0ms)
ActionController::ParameterMissing - param is missing or the value is empty: user:
actionpack (5.0.2) lib/action_controller/metal/strong_parameters.rb:309:in `require'
app/controllers/registrations_controller.rb:15:in `sign_up_params'
app/controllers/registrations_controller.rb:3:in `new'
actionpack (5.0.2) lib/action_controller/metal/basic_implicit_render.rb:4:in `send_action'
actionpack (5.0.2) lib/abstract_controller/base.rb:188:in `process_action'
actionpack (5.0.2) lib/action_controller/metal/rendering.rb:30:in `process_action'
actionpack (5.0.2) lib/abstract_controller/callbacks.rb:20:in `block in process_action'
activesupport (5.0.2) lib/active_support/callbacks.rb:126:in `call'
activesupport (5.0.2) lib/active_support/callbacks.rb:506:in `block (2 levels) in compile'
activesupport (5.0.2) lib/active_support/callbacks.rb:455:in `call'
activesupport (5.0.2) lib/active_support/callbacks.rb:101:in `__run_callbacks__'
activesupport (5.0.2) lib/active_support/callbacks.rb:750:in `_run_process_action_callbacks'
activesupport (5.0.2) lib/active_support/callbacks.rb:90:in `run_callbacks'
actionpack (5.0.2) lib/abstract_controller/callbacks.rb:19:in `process_action'
actionpack (5.0.2) lib/action_controller/metal/rescue.rb:20:in `process_action'
actionpack (5.0.2) lib/action_controller/metal/instrumentation.rb:32:in `block in process_action'
activesupport (5.0.2) lib/active_support/notifications.rb:164:in `block in instrument'
activesupport (5.0.2) lib/active_support/notifications/instrumenter.rb:21:in `instrument'
activesupport (5.0.2) lib/active_support/notifications.rb:164:in `instrument'
actionpack (5.0.2) lib/action_controller/metal/instrumentation.rb:30:in `process_action'
actionpack (5.0.2) lib/action_controller/metal/params_wrapper.rb:248:in `process_action'
activerecord (5.0.2) lib/active_record/railties/controller_runtime.rb:18:in `process_action'
actionpack (5.0.2) lib/abstract_controller/base.rb:126:in `process'
actionview (5.0.2) lib/action_view/rendering.rb:30:in `process'
actionpack (5.0.2) lib/action_controller/metal.rb:190:in `dispatch'
actionpack (5.0.2) lib/action_controller/metal.rb:262:in `dispatch'
actionpack (5.0.2) lib/action_dispatch/routing/route_set.rb:50:in `dispatch'
actionpack (5.0.2) lib/action_dispatch/routing/route_set.rb:32:in `serve'
actionpack (5.0.2) lib/action_dispatch/routing/mapper.rb:16:in `block in <class:Constraints>'
actionpack (5.0.2) lib/action_dispatch/routing/mapper.rb:46:in `serve'
actionpack (5.0.2) lib/action_dispatch/journey/router.rb:39:in `block in serve'
actionpack (5.0.2) lib/action_dispatch/journey/router.rb:26:in `serve'
actionpack (5.0.2) lib/action_dispatch/routing/route_set.rb:725:in `call'
warden (1.2.7) lib/warden/manager.rb:36:in `block in call'
warden (1.2.7) lib/warden/manager.rb:35:in `call'
rack (2.0.1) lib/rack/etag.rb:25:in `call'
rack (2.0.1) lib/rack/conditional_get.rb:25:in `call'
rack (2.0.1) lib/rack/head.rb:12:in `call'
rack (2.0.1) lib/rack/session/abstract/id.rb:222:in `context'
rack (2.0.1) lib/rack/session/abstract/id.rb:216:in `call'
actionpack (5.0.2) lib/action_dispatch/middleware/cookies.rb:613:in `call'
activerecord (5.0.2) lib/active_record/migration.rb:553:in `call'
actionpack (5.0.2) lib/action_dispatch/middleware/callbacks.rb:38:in `block in call'
activesupport (5.0.2) lib/active_support/callbacks.rb:97:in `__run_callbacks__'
activesupport (5.0.2) lib/active_support/callbacks.rb:750:in `_run_call_callbacks'
activesupport (5.0.2) lib/active_support/callbacks.rb:90:in `run_callbacks'
actionpack (5.0.2) lib/action_dispatch/middleware/callbacks.rb:36:in `call'
actionpack (5.0.2) lib/action_dispatch/middleware/executor.rb:12:in `call'
actionpack (5.0.2) lib/action_dispatch/middleware/remote_ip.rb:79:in `call'
better_errors (2.1.1) lib/better_errors/middleware.rb:84:in `protected_app_call'
better_errors (2.1.1) lib/better_errors/middleware.rb:79:in `better_errors_call'
better_errors (2.1.1) lib/better_errors/middleware.rb:57:in `call'
actionpack (5.0.2) lib/action_dispatch/middleware/debug_exceptions.rb:49:in `call'
web-console (3.4.0) lib/web_console/middleware.rb:135:in `call_app'
web-console (3.4.0) lib/web_console/middleware.rb:28:in `block in call'
web-console (3.4.0) lib/web_console/middleware.rb:18:in `call'
actionpack (5.0.2) lib/action_dispatch/middleware/show_exceptions.rb:31:in `call'
railties (5.0.2) lib/rails/rack/logger.rb:36:in `call_app'
railties (5.0.2) lib/rails/rack/logger.rb:24:in `block in call'
activesupport (5.0.2) lib/active_support/tagged_logging.rb:69:in `block in tagged'
activesupport (5.0.2) lib/active_support/tagged_logging.rb:26:in `tagged'
activesupport (5.0.2) lib/active_support/tagged_logging.rb:69:in `tagged'
railties (5.0.2) lib/rails/rack/logger.rb:24:in `call'
sprockets-rails (3.2.0) lib/sprockets/rails/quiet_assets.rb:13:in `call'
actionpack (5.0.2) lib/action_dispatch/middleware/request_id.rb:24:in `call'
rack (2.0.1) lib/rack/method_override.rb:22:in `call'
rack (2.0.1) lib/rack/runtime.rb:22:in `call'
activesupport (5.0.2) lib/active_support/cache/strategy/local_cache_middleware.rb:28:in `call'
actionpack (5.0.2) lib/action_dispatch/middleware/executor.rb:12:in `call'
actionpack (5.0.2) lib/action_dispatch/middleware/static.rb:136:in `call'
rack (2.0.1) lib/rack/sendfile.rb:111:in `call'
railties (5.0.2) lib/rails/engine.rb:522:in `call'
puma (3.7.1) lib/puma/configuration.rb:232:in `call'
puma (3.7.1) lib/puma/server.rb:578:in `handle_request'
puma (3.7.1) lib/puma/server.rb:415:in `process_client'
puma (3.7.1) lib/puma/server.rb:275:in `block in run'
puma (3.7.1) lib/puma/thread_pool.rb:120:in `block in spawn_thread'
Started POST "/__better_errors/8c394ae550fda307/variables" for ::1 at 2017-03-10 08:59:00 +0100
我终于明白这个错误是从哪里来的了。
调用参数时，只需在 create 操作中调用即可。在 new 操作中调用它们会产生错误。
编辑后的代码：
class RegistrationsController < Devise::RegistrationsController
def new
build_resource
self.resource.books = Book.new
respond_with self.resource
end
......
end