ruby-on-rails - 在Rails 4中创建API-未初始化的常量Api::V1::UsersController

Question

对于个人项目，我想在Rails 4中创建一个Restful Web服务。

因此，我使用rails-api创建了我的第一个项目，并添加以下代码:

MyProject> config目录中的routes.rb

MyProject::Application.routes.draw do
    namespace :api, defaults: {format: 'json'} do
        namespace :v1 do
            resources :users
        end
    end
end

MyProject>应用程序> Controller > api> v1>用户目录中的 users_controller.rb

module Api
    module V1
        class UsersController < ApplicationController
            def index
            end

            def create
            end

            def show
            end

            def update
            end

            def delete
            end
        end 
    end
end

当我使用命令行 rails s启动Rails服务器并转到以下URL: http://localhost:3000/api/v1/users/show时，出现以下错误:

uninitialized constant Api::V1::UsersController

Rails.root: /Users/Jean/Development/MyProject

Application Trace | Framework Trace | Full Trace activesupport (4.0.4) lib/active_support/inflector/methods.rb:228:in const_get'
activesupport (4.0.4) lib/active_support/inflector/methods.rb:228:in
block in constantize' activesupport (4.0.4) lib/active_support/inflector/methods.rb:224:in each' activesupport
(4.0.4) lib/active_support/inflector/methods.rb:224:ininject' activesupport (4.0.4) lib/active_support/inflector/methods.rb:224:in constantize' actionpack (4.0.4)
lib/action_dispatch/routing/route_set.rb:76:incontroller_reference' actionpack (4.0.4) lib/action_dispatch/routing/route_set.rb:66:in controller' actionpack (4.0.4)
lib/action_dispatch/routing/route_set.rb:44:incall' actionpack (4.0.4) lib/action_dispatch/journey/router.rb:71:in block in call'
actionpack (4.0.4) lib/action_dispatch/journey/router.rb:59:ineach' actionpack (4.0.4) lib/action_dispatch/journey/router.rb:59:in call'
actionpack (4.0.4) lib/action_dispatch/routing/route_set.rb:674:in
call' rack (1.5.2) lib/rack/etag.rb:23:in call' rack (1.5.2)
lib/rack/conditionalget.rb:25:incall' rack (1.5.2) lib/rack/head.rb:11:in call' actionpack (4.0.4)
lib/action_dispatch/middleware/params_parser.rb:27:incall' activerecord (4.0.4) lib/active_record/query_cache.rb:36:in call'
activerecord (4.0.4)
lib/active_record/connection_adapters/abstract/connection_pool.rb:626:in
call' activerecord (4.0.4) lib/active_record/migration.rb:373:in call' actionpack (4.0.4)
lib/action_dispatch/middleware/callbacks.rb:29:inblock in call' activesupport (4.0.4) lib/active_support/callbacks.rb:373:in _run__4323212420903942114__call__callbacks' activesupport (4.0.4)
lib/active_support/callbacks.rb:80:inrun_callbacks' actionpack (4.0.4) lib/action_dispatch/middleware/callbacks.rb:27:in call'
actionpack (4.0.4) lib/action_dispatch/middleware/reloader.rb:64:in
call' actionpack (4.0.4) lib/action_dispatch/middleware/remote_ip.rb:76:in call' actionpack
(4.0.4) lib/action_dispatch/middleware/debug_exceptions.rb:17:in
call' actionpack (4.0.4) lib/action_dispatch/middleware/show_exceptions.rb:30:in call'
railties (4.0.4) lib/rails/rack/logger.rb:38:incall_app' railties (4.0.4) lib/rails/rack/logger.rb:20:in block in call' activesupport
(4.0.4) lib/active_support/tagged_logging.rb:68:inblock in tagged' activesupport (4.0.4) lib/active_support/tagged_logging.rb:26:in tagged' activesupport (4.0.4)
lib/active_support/tagged_logging.rb:68:intagged' railties (4.0.4) lib/rails/rack/logger.rb:20:in call' actionpack (4.0.4)
lib/action_dispatch/middleware/request_id.rb:21:incall' rack (1.5.2) lib/rack/runtime.rb:17:in call' activesupport (4.0.4)
lib/active_support/cache/strategy/local_cache.rb:83:incall' rack (1.5.2) lib/rack/lock.rb:17:in call' actionpack (4.0.4)
lib/action_dispatch/middleware/static.rb:64:incall' railties (4.0.4) lib/rails/engine.rb:511:in call' railties (4.0.4)
lib/rails/application.rb:97:incall' rack (1.5.2) lib/rack/lock.rb:17:in call' rack (1.5.2)
lib/rack/content_length.rb:14:incall' rack (1.5.2) lib/rack/handler/webrick.rb:60:in service'
/Users/Jean/.rvm/rubies/ruby-2.1.2/lib/ruby/2.1.0/webrick/httpserver.rb:138:in
service' /Users/Jean/.rvm/rubies/ruby-2.1.2/lib/ruby/2.1.0/webrick/httpserver.rb:94:in run'
/Users/Jean/.rvm/rubies/ruby-2.1.2/lib/ruby/2.1.0/webrick/server.rb:295:in
block in start_thread'

我在Stackoverflow上发现了很多帖子，但都出现了相同的错误，但是答案并没有帮助我解决问题。

谢谢 !

Answer 1

如果您有以下路径:

MyProject > app > controllers > api > v1 > users

Controller 应为 class Api::V1::Users::UsersController 如果这:

MyProject > app > controllers > api > v1 > users_controller.rb

然后 class Api::V1::UsersController
对于首字母缩写词 API::V1::UsersController而不是 Api::V1::Users::UsersController，请使用偏转器:

用 config/initializers/inflections.rb

 ActiveSupport::Inflector.inflections(:en) do |inflect|
   inflect.acronym 'API'
 end