Rails XML构建器未呈现 [英] Rails XML builder not rendering

问题描述

在Rails 4应用程序的请求响应正文中呈现XML时遇到问题。在下面的示例中，响应主体为空白。我已经在模板中放置了调试器，所以我知道它会在模板中运行，但是不会渲染任何东西。

I’m having an issue rendering XML in the response body of a request in a Rails 4 application. In the example below the response body is blank. I’ve put a debugger in the template so I know it runs through it but doesn’t render anything out.

我创建了一个简单的Rails应用程序来演示这个问题正在使用生成器返回xml。谁能指出我这个示例的问题（可能是愚蠢的简单问题）？

I created a simple rails app to demonstrate the issue I’m having using builder to return xml. Can anyone point me to the (probably stupid simple) problem with this example?

以下是控制器，模板和测试：

Here are the controller, template, and test:

controllers / bars_controller.rb

controllers/bars_controller.rb

require 'builder'

class BarsController < ApplicationController
  before_action :set_bar, only: [:show]

  # GET /bars/1
  # GET /bars/1.json
  def show
    @xml = Builder::XmlMarkup.new
    render template: 'bars/show.xml.builder', formats: [:xml]
  end

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

    # Never trust parameters from the scary internet, only allow the white list through.
    def bar_params
      params.require(:bar).permit(:foo, :bar)
    end
 end

/views/bars/show.xml.builder

/views/bars/show.xml.builder

@xml.instruct!
@xml.bar do
  @xml.foo(@bar.foo)
  @xml.bar(@bar.bar)
end

/test/controllers/bars_controller_test.rb

/test/controllers/bars_controller_test.rb

 require 'test_helper'

 class BarsControllerTest < ActionController::TestCase
  setup do
    @bar = bars(:one)
  end

  test "should show bar" do
    get :show, id: @bar
    assert_response :success
    assert_match "<bar>", response.body
  end
 end

调试会话

     1: @xml.instruct!
     2: binding.pry
  => 3: @xml.bar do
     4:   @xml.foo(@bar.foo)
     5:   @xml.bar(@bar.bar)
     6: end

     [2] pry(#<#<Class:0x007fc669e9f610>>)> @xml.bar do
     [2] pry(#<#<Class:0x007fc669e9f610>>)*   @xml.foo(@bar.foo)  
     [2] pry(#<#<Class:0x007fc669e9f610>>)*   @xml.bar(@bar.bar)  
     [2] pry(#<#<Class:0x007fc669e9f610>>)* end  
      => "<?xml version=\"1.0\" encoding=\"UTF-8\"?><bar><foo>MyString</foo><bar>MyString</bar></bar>"

推荐答案

看起来就像创建<$ c的实例$ c> Builder :: XmlMarkup.new 是您的问题。删除显式创建的生成器，使您的控制器如下所示：

It looks like creating the instance of the Builder::XmlMarkup.new is your problem. Remove the explicit creation of the builder so your controller looks like this:

def show
  # You can also simplify by removing "bars/"
  render 'bars/show.xml.builder', formats: [:xml]
end

您的视图应如下所示：

xml.instruct!
xml.bar do
  xml.foo(@bar.foo)
  xml.bar(@bar.bar)
end

这篇关于Rails XML构建器未呈现的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！