问题
I've encountered an unexpected error while following Michael Hartl's Rails Tutorial. It had been smooth sailing.
I first saw that I was getting a different "Action Controller: Exception caught" error than the Tutorial following the completion of Hartl's Listing 7.3.
Specifically, when trying to reach /users/1, I get:
NoMethodError in UsersController#show
undefined method `key?' for nil:NilClass
I continued on through Listing 7.5 - adding a view for for a User's show action and then adding the show action to the Users controller - which resolved the error Hartl was getting, but these steps didn't resolve my error.
Based on this question, I've verified that my app/models/user.rb is free of typos: after scouring it for typos, I copied & pasted Hartl's code into my file for good measure.
Any guidance on where else to look for typos/issues would be much appreciated.
EDIT 1: As requested, the UsersController#show method:
def show
@user = User.find(params[:id])
end
EDIT 2: Full trace:
actionpack (3.2.8) lib/action_controller/metal/hide_actions.rb:36:in `visible_action?'
actionpack (3.2.8) lib/action_controller/metal/hide_actions.rb:18:in `method_for_action'
actionpack (3.2.8) lib/action_controller/metal/implicit_render.rb:14:in `method_for_action'
actionpack (3.2.8) lib/action_controller/metal/compatibility.rb:61:in `method_for_action'
actionpack (3.2.8) lib/abstract_controller/base.rb:115:in `process'
actionpack (3.2.8) lib/abstract_controller/rendering.rb:45:in `process'
actionpack (3.2.8) lib/action_controller/metal.rb:203:in `dispatch'
actionpack (3.2.8) lib/action_controller/metal/rack_delegation.rb:14:in `dispatch'
actionpack (3.2.8) lib/action_controller/metal.rb:246:in `block in action'
actionpack (3.2.8) lib/action_dispatch/routing/route_set.rb:73:in `call'
actionpack (3.2.8) lib/action_dispatch/routing/route_set.rb:73:in `dispatch'
actionpack (3.2.8) lib/action_dispatch/routing/route_set.rb:36:in `call'
journey (1.0.4) lib/journey/router.rb:68:in `block in call'
journey (1.0.4) lib/journey/router.rb:56:in `each'
journey (1.0.4) lib/journey/router.rb:56:in `call'
actionpack (3.2.8) lib/action_dispatch/routing/route_set.rb:600:in `call'
actionpack (3.2.8) lib/action_dispatch/middleware/best_standards_support.rb:17:in `call'
rack (1.4.1) lib/rack/etag.rb:23:in `call'
rack (1.4.1) lib/rack/conditionalget.rb:25:in `call'
actionpack (3.2.8) lib/action_dispatch/middleware/head.rb:14:in `call'
actionpack (3.2.8) lib/action_dispatch/middleware/params_parser.rb:21:in `call'
actionpack (3.2.8) lib/action_dispatch/middleware/flash.rb:242:in `call'
rack (1.4.1) lib/rack/session/abstract/id.rb:205:in `context'
rack (1.4.1) lib/rack/session/abstract/id.rb:200:in `call'
actionpack (3.2.8) lib/action_dispatch/middleware/cookies.rb:339:in `call'
activerecord (3.2.8) lib/active_record/query_cache.rb:64:in `call'
activerecord (3.2.8) lib/active_record/connection_adapters/abstract/connection_pool.rb:473:in `call'
actionpack (3.2.8) lib/action_dispatch/middleware/callbacks.rb:28:in `block in call'
activesupport (3.2.8) lib/active_support/callbacks.rb:405:in `_run__3560654018285941260__call__3098371293035639072__callbacks'
activesupport (3.2.8) lib/active_support/callbacks.rb:405:in `__run_callback'
activesupport (3.2.8) lib/active_support/callbacks.rb:385:in `_run_call_callbacks'
activesupport (3.2.8) lib/active_support/callbacks.rb:81:in `run_callbacks'
actionpack (3.2.8) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
actionpack (3.2.8) lib/action_dispatch/middleware/reloader.rb:65:in `call'
actionpack (3.2.8) lib/action_dispatch/middleware/remote_ip.rb:31:in `call'
actionpack (3.2.8) lib/action_dispatch/middleware/debug_exceptions.rb:16:in `call'
actionpack (3.2.8) lib/action_dispatch/middleware/show_exceptions.rb:56:in `call'
railties (3.2.8) lib/rails/rack/logger.rb:26:in `call_app'
railties (3.2.8) lib/rails/rack/logger.rb:16:in `call'
actionpack (3.2.8) lib/action_dispatch/middleware/request_id.rb:22:in `call'
rack (1.4.1) lib/rack/methodoverride.rb:21:in `call'
rack (1.4.1) lib/rack/runtime.rb:17:in `call'
activesupport (3.2.8) lib/active_support/cache/strategy/local_cache.rb:72:in `call'
rack (1.4.1) lib/rack/lock.rb:15:in `call'
actionpack (3.2.8) lib/action_dispatch/middleware/static.rb:62:in `call'
railties (3.2.8) lib/rails/engine.rb:479:in `call'
railties (3.2.8) lib/rails/application.rb:223:in `call'
rack (1.4.1) lib/rack/content_length.rb:14:in `call'
railties (3.2.8) lib/rails/rack/log_tailer.rb:17:in `call'
rack (1.4.1) lib/rack/handler/webrick.rb:59:in `service'
/Users/aaronmacy/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/1.9.1/webrick/httpserver.rb:138:in `service'
/Users/aaronmacy/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/1.9.1/webrick/httpserver.rb:94:in `run'
/Users/aaronmacy/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/1.9.1/webrick/server.rb:191:in `block in start_thread'
EDIT 3: users_controller.rb:
class UsersController < ApplicationController
def show
@user = User.find(params[:id])
end
def new
end
end
user.rb:
class User < ActiveRecord::Base
attr_accessible :name, :email, :password, :password_confirmation
has_secure_password
before_save { self.email.downcase! }
validates :name, presence: true, length: { maximum: 50 }
VALID_EMAIL_REGEX = /\A[\w+\-.]+@[a-z\d\-.]+\.[a-z]+\z/i
validates :email, presence: true,
format: { with: VALID_EMAIL_REGEX },
uniqueness: { case_sensitive: false }
validates :password, presence: true, length: { minimum: 6 }
validates :password_confirmation, presence: true
end
routes.rb:
SampleApp::Application.routes.draw do
resources :users
root to: 'static_pages#home'
match '/signup', to: 'users#new'
match '/help', to: 'static_pages#help'
match '/about', to: 'static_pages#about'
match '/contact', to: 'static_pages#contact'
end
回答1:
This is a bcrypt issue. Verify that you have uncommented bcrypt in your Gemfile, run bundle install, and then restarted the server.
See: undefined method `key?' for nil:NilClass with bcrypt-ruby and has_secure_password
来源：https://stackoverflow.com/questions/12791545/nomethoderror-in-userscontrollershow-undefined-method-key-for-nilnilclass