从 Rails 嵌套表单访问参数

Question

我有一个 Rails 表单，其中包含用于生成 Stripe 支付表单的脚本。嵌套在表单中的是fields_for 标记。这是我的全部费用/new.html.erb 文件：

<div class="row">

    <div class="col-md-2"></div>  


      <div class="col-md-8">

      <h3>Confirm address and make payment</h3>
      <br>  

      <%= form_tag charges_path do %>

         <%= fields_for :charges do |f| %>

          <div class="field">
            <%= f.label :first_name %>
            <%= f.text_field :first_name, size: 20, :value => current_user.first_name, :class => 'form-control' %>
          </div>

          <div class="field">
            <%= f.label :last_name %>
            <%= f.text_field :last_name, size: 20, :value => current_user.last_name, :class => 'form-control' %>
          </div>

          <div class="field">
            <%= f.label :address %>
            <%= f.text_area :address, size: 40, :value => current_user.address, :class => 'form-control' %>
          </div>

          <div class="field">
            <%= f.label :city %>
            <%= f.text_field :city, size: 20, :value => current_user.city, :class => 'form-control' %>
          </div>  

          <div class="field">
            <%= f.label :state %>
            <%= f.text_field :state, size: 2, :value => current_user.state, :class => 'form-control' %>
          </div>  

          <div class="field">
            <%= f.label :email %>
            <%= f.text_field :email, size: 40, :value => current_user.email, :class => 'form-control' %>
          </div>

          <%= f.hidden_field :total_price, :value => @cart.total_price  %>

          <% end %>

        <br>

          <article>
              <% if flash[:error].present? %>
                <div id="error_explanation">
                  <p><%= flash[:error] %></p>
                </div>
              <% end %>
              <label class="amount">
                <span>Amount: <%= number_to_currency(@cart.total_price * 7.35) %></span>
              </label>
          </article>

          <script src="https://checkout.stripe.com/checkout.js" class="stripe-button"
                  data-key="<%= Rails.configuration.stripe[:publishable_key] %>"
                  data-description="A one-time payment"
                  data-amount="<%= @cart.total_price * 735 %>"
                  data-locale="auto"></script>
        <% end %>



      </div>

      <div class="col-md-2"></div>  



    </div>

这是我的收费控制器：

class ChargesController < ApplicationController
    include CurrentCart
    before_action :set_cart, only: [:new, :create]
    #before_action :set_charge, only: [:create]

    def new
        #@charge = Charge.new
    end

    def create #METHOD IS CALLED AFTER PAYMENT IS MADE
    # Amount in cents

    @charge = Charge.new(charge_params)
    @amount = (@cart.total_price * 735) 


    customer = Stripe::Customer.create(
      :email => params[:stripeEmail],
      :source  => params[:stripeToken]
    )

    charge = Stripe::Charge.create(
      :customer    => customer.id,
      :amount      => @amount,
      :description => 'Witch or Wizard',
      :currency    => 'usd'
    )

    Cart.destroy(session[:cart_id]) 

    rescue Stripe::CardError => e
      flash[:error] = e.message
      redirect_to new_charge_path
    end

    private
    # Use callbacks to share common setup or constraints between actions.
    def set_charge
      @charge = Charge.find(params[:id])
    end

    # Never trust parameters from the scary internet, only allow the white list through.
    def charge_params
      params.permit(:first_name, :last_name, :address, :city, :state, :email, :total_price)
    end

end

当我提交此表单时，我收到与我的 set_charge 方法有关的错误：

找不到带有 'id'= 的 Charge

我在这里做错了什么？ Stripe 功能运行良好，但我也在尝试将表单中包含的客户信息保存到数据库中。

这是我提交表单时的日志：

    Started POST "/charges" for 127.0.0.1 at 2017-07-16 20:45:24 -0400
Processing by ChargesController#create as HTML
  Parameters: {"utf8"=>"✓", "authenticity_token"=>"9Kj986IJXX+NQuJ3msJelyYSYQfmQa+i+kmqdseoidR11mmt2T6xZrXi/WtgjAb2u6zs4GRF9nIr6/ZW3U4F/g==", "charges"=>{"first_name"=>"Matt", "last_name"=>"Cole", "address"=>"1 South Main St", "city"=>"Marietta", "state"=>"GA", "email"=>"mattaecole@gmail.com", "total_price"=>"4"}, "stripeToken"=>"tok_1AgNMTJG64O6iQtfUhLFVKZF", "stripeTokenType"=>"card", "stripeEmail"=>"mattaecole@gmail.com"}
  Cart Load (0.2ms)  SELECT  "carts".* FROM "carts" WHERE "carts"."id" = ? LIMIT ?  [["id", 71], ["LIMIT", 1]]
  LineItem Load (0.7ms)  SELECT "line_items".* FROM "line_items" WHERE "line_items"."cart_id" = ?  [["cart_id", 71]]
  Product Load (0.1ms)  SELECT  "products".* FROM "products" WHERE "products"."id" = ? LIMIT ?  [["id", 17], ["LIMIT", 1]]
  CACHE (0.0ms)  SELECT  "carts".* FROM "carts" WHERE "carts"."id" = ? LIMIT ?  [["id", 71], ["LIMIT", 1]]
   (0.1ms)  begin transaction
  CACHE (0.0ms)  SELECT "line_items".* FROM "line_items" WHERE "line_items"."cart_id" = ?  [["cart_id", 71]]
  SQL (0.3ms)  DELETE FROM "line_items" WHERE "line_items"."id" = ?  [["id", 135]]
  SQL (0.1ms)  DELETE FROM "carts" WHERE "carts"."id" = ?  [["id", 71]]
   (1.7ms)  commit transaction
  Rendering charges/create.html.erb within layouts/application
  Rendered charges/create.html.erb within layouts/application (1.0ms)
  User Load (0.4ms)  SELECT  "users".* FROM "users" WHERE "users"."id" = ? ORDER BY "users"."id" ASC LIMIT ?  [["id", 7], ["LIMIT", 1]]
Completed 200 OK in 1529ms (Views: 61.8ms | ActiveRecord: 6.0ms)

Answer 1

问题是提交表单后没有发送id，所以报错。

但是，您根本不需要该方法，因为您正在创建Charge，而它的id 尚未创建。并且，在create 操作的第一行替换@charge（在set_charge 中设置），即：

@charge = Charge.new(charge_params)

要修复错误，只需从控制器中删除以下行，您应该没问题：

before_action :set_charge, only: [:create]

---

一般来说，您只需要在更新记录时使用此类回调（即用于查找现有记录），即仅使用 edit 和 update 操作。

因此，如果您打算将此类操作添加到您的控制器，请将上面的行（而不是删除它）更改为仅对 edit 和 update 操作执行：

before_action :set_charge, only: [:edit, :update]