Rails XML builder not rendering

Question

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.

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?

Here are the controller, template, and test:

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

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

/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

debugging session

     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>"

Yes. The test creates the entity and then displays it. If I debug the template then I can render the xml just fine manually in the debugging session. However, it doesn’t get pushed to the response.body. — Nate Bird
– Nate Bird, Commented May 6, 2015 at 13:58

Gavin Miller · Accepted Answer · 2015-05-06 14:07:47Z

7

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

And your view should look like this:

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

edited May 6, 2015 at 14:07

answered May 6, 2015 at 14:01

Gavin Miller

44k22 gold badges130 silver badges191 bronze badges

Sign up to request clarification or add additional context in comments.

7 Comments

Nate Bird Over a year ago

The first part of you answer doesn’t matter according to the Rails guides: guides.rubyonrails.org/….

Nate Bird Over a year ago

The second part makes it work! Thanks! Now to figure out why. :-)

Gavin Miller Over a year ago

Yup, you're right -- red herring. I'm not super familiar with the XmlBuilder

Nate Bird Over a year ago

Yes, I think the explicit creation of the XML builder is causing the issue. Thanks for the help.

Nate Bird Over a year ago

These days, who is familiar with XmlBuilder? :-)

|

Collectives™ on Stack Overflow

Rails XML builder not rendering

1 Answer 1

7 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

7 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related