Rails - 将客户端 model 保存到数据库中

Question

Hey here. I'm kinda new to Rails and I've been trying to find some answers but no luck yet so here we go.

I've set up a basic Rails app and just trying to save a Client to my database with a validation but nothing seems to be coming together. Anyone could point me to the right direction please or let me know what I've been doing wrong in my code.

I keep getting errors like this:

NoMethodError in Clients#new
Showing /Users/******/Documents/******/*****/app/views/clients/_form.html.erb where line #1 raised:

undefined method `clients_path' for #<ActionView::Base:0x00000000064a50>
Did you mean?  clients_new_path

Even if I remove @client = Client.new from the new method I can view the page but nothing gets saved.

I'm stuck really now so any help much appreciated! Thanks!

My Routes.rb file:

Rails.application.routes.draw do
  mount RailsAdmin::Engine => '/admin', as: 'rails_admin'
  get 'dashboard/index'
  root to: "home#index"

  devise_for :users, controllers: {
    sessions: 'users/sessions',
    passwords: 'users/passwords',
    registrations: 'users/registrations'
  }

  get '/clients/index'
  get '/clients/new'
  get '/clients/edit'
  get '/clients/delete'

  get '/clients/:id', to: 'clients#show'

  post '/clients/new', to: 'clients#create'
end

My Dashboard file:

<% if user_signed_in? %>
    <nav class="subnav">
        <ul>
            <li><%= link_to('My Clients', clients_index_path) %></li>
            <li><%= link_to('Add Client', clients_new_path) %></li>
            <li><%= link_to('Edit registration', edit_user_registration_path) %></li>
            <li><%= link_to('Logout', destroy_user_session_path, :method => :delete) %></li>
        </ul>
    </nav>
<% else %>

  <%= link_to('Register', new_user_registration_path)  %>
  <%= link_to('Login', new_user_session_path)  %>

<% end %>

My ClientsController file:

class ClientsController < ApplicationController
  def index
    @clients = Client.all
  end

  def new
    @client = Client.new
  end

  def show
    @client = Client.find(params[:id])
  end

  def create
    @client = Client.new(client_params)

    if @client.save
      redirect_to @client
    else
      render :new
    end
  end

  def edit
  end

  def delete
  end

  private
    def client_params
      params.require(:client).permit(:name, :provider)
    end
end

My form :

<%= form_with model: @client do |form| %>
  <div>
    <%= form.label :name %><br>
    <%= form.text_field :name %>
    <% client.errors.full_messages_for(:name).each do |message| %>
      <div><%= message %></div>
    <% end %>
  </div>

  <div>
    <%= form.label :provider %><br>
    <%= form.text_field :provider %>
  </div>

  <div>
    <%= form.label :business_type %><br>
    <%= form.select :business_type, ["Partnership", "Sole Trader", "Limited Company"] %>
  </div>

  <div>
    <%= form.submit %>
  </div>
<% end %>

Finally my new.html.erb file:

<h1>Clients#new</h1>

<%= render 'form', client: @client %>

Answer 1

clients_path is generated by resources:clients, only: :index or you probably need to give your route the name you want. Try this

get '/clients/index', as: :clients

or, if you want to specify non default paths as you're doing, your index is probably called clients_index_path , but you can check that with a rake routes or rails routes , because I'm not sure.

That said, I suggest you to go with the resources method in your routes file and use the default paths as you're trying to do. Something like

resources :clients

but now you don't have a path like /clients/index no more, just /clients for the index action.

If you're in doubts with routes try to read the guide about routing

Answer 2

The Rails way to declare the routes to Create, Update, Read and Destroy (CRUD) a resource is just:

Rails.application.routes.draw do
  mount RailsAdmin::Engine => '/admin', as: 'rails_admin'
  get 'dashboard/index'
  root to: "home#index"

  devise_for :users, controllers: {
    sessions: 'users/sessions',
    passwords: 'users/passwords',
    registrations: 'users/registrations'
  }

  resources :clients
end

As you can see by the annotions above each method Rails does not add the "action" to the path except for the new and edit routes:

class ClientsController < ApplicationController
  before_action :set_client, only: [:show, :edit, :update, :destroy]

  # GET /clients
  def index
    @clients = Client.all
  end

  # GET /clients/1
  def show
  end
  
  # GET /clients/new
  def new
    @client = Client.new
  end

  # POST /clients
  def create
    @client = Client.new(client_params)

    if @client.save
      redirect_to @client
    else
      render :new
    end
  end

  # GET /clients/edit
  def edit
  end

  # PATCH /clients/1
  def update
    if @client.update(client_params)
      redirect_to @client
    else
      render :edit
    end
  end

  # DELETE /clients/1
  def delete
    @client.destroy
    redirect_to action: :index, 
                notice: 'Client deleted'
  end

  private
    def set_client
      @client = Client.find(params[:id])
    end

    def client_params
      params.require(:client).permit(:name, :provider)
    end
end

Thus you don't create resources with post '/clients/new' - You use POST /clients . Also when you use the "bare-bones" routing methods such as match , get , post etc Rails does not automatically add routing helper. If you actually wanted to generate the equivilent routes you would need to use:

post '/clients', 
  to: 'clients#create',
  as: :clients

But you're much better off embracing the conventions and learning to use them to be productive.