使用 Ruby on Rails 提交后出现路由错误

Question

每当我按下提交按钮时，都会显示错误消息：No route matches [POST] "/contacts/new"。我刚开始学习 Ruby on Rails，我不知道如何解决这个问题。非常感谢任何帮助！谢谢:)

Rails.application.routes.draw do
 root to: 'pages#home'
 get 'about', to: 'pages#about'
 resources :contacts
end

上面是我的路由文件

class ContactsController < ApplicationController
    def new
      @contact = Contact.new
    end
    def create
      @contact = Contact.new(contact_params)
      if @contact.save
         redirect_to new_contact_path, notice: "Message sent."
      else
         redirect_to new_contact_path, notice: "Error occured."
      end
    end
    private
      def contact_params
         params.require(:contact).permit(:name, :email, :comments)
      end
end

上面是我的控制器文件

<div class="container">
  <div class="row">
    
    <h3 class="text-center">Contact us</h3>
    
    <div class="col-md-4 col-md-offset-4">
      <%= flash[:notice] %>
      <div class="well">
        <%= form_for @contact do |f| %>
        
          <div class="form-group">
          <%= f.label :name %>
          <%= f.text_field :name, class: 'form-control' %>
          </div>
          
          <div class="form-group">
          <%= f.label :email %>
          <%= f.text_field :email, class: 'form-control' %>
          </div>
          
          <div class="form-group">
          <%= f.label :comments %>
          <%= f.text_area :comments, class: 'form-control' %>
          </div>
          
          <%= f.submit 'Submit', class: 'btn btn-default' %>
        <% end %>
      </div>
    </div>
  </div>
</div>

以上是我的视图文件

class CreateContacts < ActiveRecord::Migration[5.0]
  def change
    create_table :contacts do |t|
      t.string :name
      t.string :email
      t.text :comments
      t.timestamps
    end
  end
end

以上是我的迁移文件

ActiveRecord::Schema.define(version: 20210210035931) do

  create_table "contacts", force: :cascade do |t|
  end

end

上面是我的 schema.rb 文件。我在这里有一个问题：根据我所学到的，我会有列（例如t.string "email" 在 schema.rb 文件中自动生成，但它在我的文件中显示为空。这正常吗？手动添加列但路由错误仍然存​​在。

class Contact < ActiveRecord::Base
    
end

以上是我的联系人模型文件 (contact.rb)

Started GET "/contacts/new" for 128.106.252.65 at 2021-02-17 12:25:05 +0000
Cannot render console from 128.106.252.65! Allowed networks: 127.0.0.1, ::1, 127.0.0.0/127.255.255.255
Processing by ContactsController#new as HTML
  Rendering contacts/new.html.erb within layouts/application
  Rendered contacts/new.html.erb within layouts/application (3.1ms)
Completed 200 OK in 54ms (Views: 52.4ms | ActiveRecord: 0.0ms)


Started POST "/contacts/new" for 128.106.252.65 at 2021-02-17 12:25:08 +0000
Cannot render console from 128.106.252.65! Allowed networks: 127.0.0.1, ::1, 127.0.0.0/127.255.255.255
  
ActionController::RoutingError (No route matches [POST] "/contacts/new"):
  
actionpack (5.0.0) lib/action_dispatch/middleware/debug_exceptions.rb:53:in `call'
web-console (3.7.0) lib/web_console/middleware.rb:135:in `call_app'
web-console (3.7.0) lib/web_console/middleware.rb:22:in `block in call'
web-console (3.7.0) lib/web_console/middleware.rb:20:in `catch'
web-console (3.7.0) lib/web_console/middleware.rb:20:in `call'
actionpack (5.0.0) lib/action_dispatch/middleware/show_exceptions.rb:31:in `call'
railties (5.0.0) lib/rails/rack/logger.rb:36:in `call_app'
railties (5.0.0) lib/rails/rack/logger.rb:24:in `block in call'
activesupport (5.0.0) lib/active_support/tagged_logging.rb:70:in `block in tagged'
activesupport (5.0.0) lib/active_support/tagged_logging.rb:26:in `tagged'
activesupport (5.0.0) lib/active_support/tagged_logging.rb:70:in `tagged'
railties (5.0.0) lib/rails/rack/logger.rb:24:in `call'
sprockets-rails (3.2.2) lib/sprockets/rails/quiet_assets.rb:13:in `call'
actionpack (5.0.0) lib/action_dispatch/middleware/request_id.rb:24:in `call'
rack (2.2.3) lib/rack/method_override.rb:24:in `call'
rack (2.2.3) lib/rack/runtime.rb:22:in `call'
activesupport (5.0.0) lib/active_support/cache/strategy/local_cache_middleware.rb:28:in `call'
actionpack (5.0.0) lib/action_dispatch/middleware/executor.rb:12:in `call'
actionpack (5.0.0) lib/action_dispatch/middleware/static.rb:136:in `call'
rack (2.2.3) lib/rack/sendfile.rb:110:in `call'
railties (5.0.0) lib/rails/engine.rb:522:in `call'
puma (3.4.0) lib/puma/configuration.rb:224:in `call'
puma (3.4.0) lib/puma/server.rb:569:in `handle_request'
puma (3.4.0) lib/puma/server.rb:406:in `process_client'
puma (3.4.0) lib/puma/server.rb:271:in `block in run'
puma (3.4.0) lib/puma/thread_pool.rb:114:in `block in spawn_thread'
  Rendering /home/ec2-user/.rvm/gems/ruby-2.3.0@saasapp/gems/actionpack-5.0.0/lib/action_dispatch/middleware/templates/rescues/routing_error.html.erb within rescues/layout
  Rendering /home/ec2-user/.rvm/gems/ruby-2.3.0@saasapp/gems/actionpack-5.0.0/lib/action_dispatch/middleware/templates/rescues/_trace.html.erb
  Rendered /home/ec2-user/.rvm/gems/ruby-2.3.0@saasapp/gems/actionpack-5.0.0/lib/action_dispatch/middleware/templates/rescues/_trace.html.erb (1.4ms)
  Rendered collection of /home/ec2-user/.rvm/gems/ruby-2.3.0@saasapp/gems/actionpack-5.0.0/lib/action_dispatch/middleware/templates/routes/_route.html.erb [10 times] (3.0ms)
  Rendered /home/ec2-user/.rvm/gems/ruby-2.3.0@saasapp/gems/actionpack-5.0.0/lib/action_dispatch/middleware/templates/routes/_table.html.erb (0.9ms)
  Rendering /home/ec2-user/.rvm/gems/ruby-2.3.0@saasapp/gems/actionpack-5.0.0/lib/action_dispatch/middleware/templates/rescues/_request_and_response.html.erb
  Rendered /home/ec2-user/.rvm/gems/ruby-2.3.0@saasapp/gems/actionpack-5.0.0/lib/action_dispatch/middleware/templates/rescues/_request_and_response.html.erb (1.2ms)
  Rendered /home/ec2-user/.rvm/gems/ruby-2.3.0@saasapp/gems/actionpack-5.0.0/lib/action_dispatch/middleware/templates/rescues/routing_error.html.erb within rescues/layout (27.1ms)

以上是完整的堆栈跟踪。

Routing Error Message screenshot

Answer 1

当您向资源提交表单时，应将其提交给[POST] /contacts/ 而不是[POST] /contacts/new，如错误中所述。

您应该更新您的表单以提交到正确的路径。

提示：在终端中使用rails routes 命令查看应用程序中的所有路由。