respond_with returns " " on PUT and DELETE verb

This is just an example.
Real code below

  def create
    @user = User.new(params[:user])
    if can? :create, @user
      @user.save
      respond_with(@user)
    else
      raise SWC::Exceptions.new(I18n.t('user.errors.insufficientAccountPermissions'))
    end
  end

  def show
    @user = User.find(params[:id])
    if can? :read, @user
      respond_with(@user)
    else
      raise SWC::Exceptions.new(I18n.t('user.errors.insufficientAccountPermissions'))
    end
  end

  def update
    @user = User.find(:id => params[:id])
    if can? :update, @user
      @user.update_attributes(params[:user])
      respond_with(@user)
    else
      raise SWC::Exceptions.new(I18n.t('user.errors.insufficientAccountPermissions'))
    end
  end

  def destroy
    @user = User.find(params[:id])
    if can? :destroy, @user
      @user.destroy
      respond_with(I18n.t('user.successful.accountDestroyed'))
    else
      raise SWC::Exceptions.new(I18n.t('user.errors.insufficientAccountPermissions'))
    end
  end

If I try to remove non-existent user I get " " rather than the error in JSON format

Sorry to resurrect this ticket but what is the solution here? As far as I can see both update and destroy should return something for say a json response as otherwise the client will error, not being able to pass an empty string as json.

Sorry, should have said that to get around this I am currently using this for the json response:

render :text => '{}', :status => :ok

This is the only way to get Rails to play nice with libraries such as http://github.com/benpickles/js-model

I ran into this issue today too. As is, respond_with is not helpful for any API that expects JSON to be returned.

This ticket should be reopened.

Can you try writing a test for this? I think you should try writing it in actionpack/test/controller/mime_responds_test.rb

The issue with this is if you are using a strict JSON parser on the client side it will try to parse " " and fail. This really depends on the client you are using. For example if I make an ajax put request with jQuery to an action that users respond_with it will always fail because it cannot parse the returned " "

$.ajax({
  url: 'http://localhost:3000/users/1.json',
  dataType: 'json',
  type: 'PUT',
  data: {
    user: {
      name: "something new"
    }
  },
  error: function(XMLHttpRequest, textStatus, errorThrown) {
     alert('error');
  },
  complete: function() {alert('complete');}
});

The error callback will always get thrown because it fails to parse the response of " ".

Personally I think Rails is behaving correctly; if it is a successful update there is no reason to return the object again since you already have it, head ok should be good enough.

The solution I have for this is on the jQuery side, I've added this line to my application.js and everything works perfectly:

jQuery.ajaxSetup({ dataFilter: function(data, type){ return (!data || jQuery.trim(data)=="") ? "{}" : data; } });

Here's a minimal test case.

## Rails 3 doesn't seem to handle PUT methods correctly.

## routing

FruitApplication::Application.routes.draw do
  resources :fruits do
    member do
      put :peel  # A HTTP PUT method that will map to fruits/:id/peel
    end
  end
end

## controller

class FruitsController < ApplicationController
  respond_to :json
  def peel
    respond_with :status => :not_found    # This appears to be ignored and 200 is returned.
  end
end

## spec

describe FruitController do
  subject { @controller }
  before(:each) { put :peel, :id => 1234 }
  it { should respond_with :not_found }
end

# Failure/Error: it { should respond_with :not_found }
# Expected response to be a 404, but was 200
# # ./spec/controllers/fruit_controller_spec.rb:3
# # /home/johnf/.rvm/gems/ruby-1.8.7-p299@project-getaroom/gems/activesupport-3.0.0/lib/active_support/dependencies.rb:239:in `inject'

Please add a test case to Rails suite?

I've ran into this issue recently as well.

The problem is with the Responder#api_behavior method:

def api_behavior(error)
  raise error unless resourceful?

  if get?
    display resource
  elsif has_errors?
    display resource.errors, :status => :unprocessable_entity
  elsif post?
    display resource, :status => :created, :location => api_location
  else
    head :ok
  end
end

In this case for PUT and DELETE verbs it does "head :ok" that, because of some strange error in some old version of Safari, actually returns a single space instead of empty body (http://dev.rubyonrails.org/changeset/1818).

For PUT verb it could simply return an updated resource in specified format - just like for POST, but with different status. However, I'm not sure if it's necessary.

For DELETE verb I guess it should return a valid, empty document - whatever this means for specified format. For JSON, "" and " " strings are not considered valid by native JSON parser in WebKit. However, "{}" is valid. Maybe we could introduce a default "empty _ #{format} _ resource" methods for JSON (not sure about XML) that would return a valid document as a string. The Responder#api_behavior method would simply check if responder responds to this method and render an empty resource using "render :text", otherwise it would fallback to "head :ok". This would allow users to add new methods to Responder class for whatever formats they use.

I'm not sure if this will actually solve this problem for JSON format, because empty string is still considered as invalid JSON - that's why most people use what Jamie mentioned before:

render :text => '{}', :status => :ok

Checking if the status is json and explicitly returning "{}" in such cases is ok. Patch with tests please?

Here's a patch that changes the behavior to return "{}" instead of " " for JSON requests with PUT and DELETE.

It also allows to add new methods to return a valid resource in any format. Currently only empty_json_resource method is defined, but if for someone " " is not a valid XML, one can easily fix it by defining AC::Responder#empty_xml_resource method and return <?xml version="1.0" encoding="UTF-8" ?>* or something similar instead.

The patch is at http://gist.github.com/620923, because I couldn't upload it here.

(from [1556e0874dd5c7e160a9bc5091dd60eb4bd5ec97]) Return a valid empty JSON on successful PUT and DELETE requests. [#5199 respond_with returns " " on PUT and DELETE verb state:resolved]

Signed-off-by: José Valim jose.valim@gmail.com
http://github.com/rails/rails/commit/1556e0874dd5c7e160a9bc5091dd60...