问题
just started learning Ruby on Rails, I'm trying to install the devise gem for creating a login/signin lesson, but I keep getting the following messages..
Could anyone help please? and feel free to correct me on how i'm asking the questions. New to this community and would love to be involved.
alexs-air:pinteresting alexkwon$ rails generate devise:install
/Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activerecord-4.1.1/lib/active_record/dynamic_matchers.rb:26:in `method_missing': undefined method `devise' for Install (call 'Install.connection' to establish a connection):Class (NoMethodError)
from /Users/alexkwon/Desktop/pinteresting/app/models/install.rb:4:in `<class:Install>'
from /Users/alexkwon/Desktop/pinteresting/app/models/install.rb:1:in `<top (required)>'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:443:in `load'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:443:in `block in load_file'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:633:in `new_constants_in'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:442:in `load_file'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:342:in `require_or_load'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:480:in `load_missing_constant'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:180:in `const_missing'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/inflector/methods.rb:238:in `const_get'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/inflector/methods.rb:238:in `block in constantize'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/inflector/methods.rb:236:in `each'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/inflector/methods.rb:236:in `inject'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/inflector/methods.rb:236:in `constantize'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:552:in `get'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:583:in `constantize'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise.rb:297:in `get'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise/mapping.rb:77:in `to'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise/mapping.rb:72:in `modules'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise/mapping.rb:89:in `routes'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise/mapping.rb:156:in `default_used_route'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise/mapping.rb:66:in `initialize'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise.rb:331:in `new'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise.rb:331:in `add_mapping'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise/rails/routes.rb:221:in `block in devise_for'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise/rails/routes.rb:220:in `each'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise/rails/routes.rb:220:in `devise_for'
from /Users/alexkwon/Desktop/pinteresting/config/routes.rb:2:in `block in <top (required)>'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/actionpack-4.1.1/lib/action_dispatch/routing/route_set.rb:335:in `instance_exec'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/actionpack-4.1.1/lib/action_dispatch/routing/route_set.rb:335:in `eval_block'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/actionpack-4.1.1/lib/action_dispatch/routing/route_set.rb:313:in `draw'
from /Users/alexkwon/Desktop/pinteresting/config/routes.rb:1:in `<top (required)>'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:241:in `load'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:241:in `block in load'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:232:in `load_dependency'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:241:in `load'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/application/routes_reloader.rb:40:in `block in load_paths'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/application/routes_reloader.rb:40:in `each'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/application/routes_reloader.rb:40:in `load_paths'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/application/routes_reloader.rb:16:in `reload!'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/application/routes_reloader.rb:26:in `block in updater'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/file_update_checker.rb:75:in `call'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/file_update_checker.rb:75:in `execute'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/application/routes_reloader.rb:27:in `updater'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/application/routes_reloader.rb:7:in `execute_if_updated'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/application/finisher.rb:71:in `block in <module:Finisher>'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/initializable.rb:30:in `instance_exec'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/initializable.rb:30:in `run'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/initializable.rb:55:in `block in run_initializers'
from /Users/alexkwon/.rvm/rubies/ruby-2.1.2/lib/ruby/2.1.0/tsort.rb:226:in `block in tsort_each'
from /Users/alexkwon/.rvm/rubies/ruby-2.1.2/lib/ruby/2.1.0/tsort.rb:348:in `block (2 levels) in each_strongly_connected_component'
from /Users/alexkwon/.rvm/rubies/ruby-2.1.2/lib/ruby/2.1.0/tsort.rb:427:in `each_strongly_connected_component_from'
from /Users/alexkwon/.rvm/rubies/ruby-2.1.2/lib/ruby/2.1.0/tsort.rb:347:in `block in each_strongly_connected_component'
from /Users/alexkwon/.rvm/rubies/ruby-2.1.2/lib/ruby/2.1.0/tsort.rb:345:in `each'
from /Users/alexkwon/.rvm/rubies/ruby-2.1.2/lib/ruby/2.1.0/tsort.rb:345:in `call'
from /Users/alexkwon/.rvm/rubies/ruby-2.1.2/lib/ruby/2.1.0/tsort.rb:345:in `each_strongly_connected_component'
from /Users/alexkwon/.rvm/rubies/ruby-2.1.2/lib/ruby/2.1.0/tsort.rb:224:in `tsort_each'
from /Users/alexkwon/.rvm/rubies/ruby-2.1.2/lib/ruby/2.1.0/tsort.rb:205:in `tsort_each'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/initializable.rb:54:in `run_initializers'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/application.rb:288:in `initialize!'
from /Users/alexkwon/Desktop/pinteresting/config/environment.rb:5:in `<top (required)>'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:247:in `require'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:247:in `block in require'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:232:in `load_dependency'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:247:in `require'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/application.rb:264:in `require_environment!'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/commands/commands_tasks.rb:147:in `require_application_and_environment!'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/commands/commands_tasks.rb:133:in `generate_or_destroy'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/commands/commands_tasks.rb:51:in `generate'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/commands/commands_tasks.rb:40:in `run_command!'
from /Users/alexkwon/.rvm/gems/ruby-2.1.2/gems/railties-4.1.1/lib/rails/commands.rb:17:in `<top (required)>'
from bin/rails:8:in `require'
from bin/rails:8:in `<main>'
回答1:
Welcome to Rails man.
I know the community is all up on the devise gem. The reality is that Devise is an advanced authentication app that's a gem.
If you're learning, and you need authentication, some super geek named Ryan Bates hooked you up with a tutorial and screencast on basic authentication that will work exactly how you need it, and you will understand what's going on:
http://railscasts.com/episodes/250-authentication-from-scratch
WHABAM!
Be mindful that is based on rails 3. Check the differences between rails, and ruby versions if you encounter problems while following directions. If you do get errors, still, this path will get your further to deploying that app of yours.
Come back to Devise when you need the features it provides, Rails, and confident you can implement ideas found in the book 'Crafting Rails Application' by José Valim. He's one of the main contributors of Devise, so you'll get insight on his thought process.
来源：https://stackoverflow.com/questions/24037007/devise-gem-install-for-ruby-on-rails