Double render error when trying to auto sign in and redirect user into a specific path after registration in Devise

Question

Hi I am getting a double redirection here

What I've been trying to accomplish is to auto sign in the user and redirect the user into a specific path, not in the root path.

In my registrations_controller.rb

def new
    @user = User.new
  end

  def create
    @user = User.new params[:user]
    @valid = @user.save
    if @valid
      sign_up
    end
    respond_to do |format|
      format.js { render layout: false }
    end
  end

  def sign_up
    sign_in(resource_name, resource)
    respond_with resource, :location => after_sign_up_path_for(resource)
  end

In my application_controller.rb

def after_sign_in_path_for(resource)
    if resource.admin? or resource.super_admin?
      admin_index_path      
    else
      if mobile_device?
        page_path("backgroundinfo")
      else
        page_path("howto")
      end
    end
  end

  def after_sign_up_path_for(resource)
    page_path("howto")
  end

Any workarounds will be appreciated.

PS: Removing the respond_with resource, :location => after_sign_up_path_for(resource) is still redirecting the user to the root_path not in the page_path maybe because the controller action is in registration?

Answer 1

A double render error happens when you try to render two templates from the same request.

Your sign_up method attempts to respond with a respond_with block, and after that your create method attempts to make another response from the respond_to block. Here is the issue:

if @valid
  sign_up
end

This calls your sign_up method which attempts to render a response. After that happens, the following block tries to render another template:

respond_to do |format|
  format.js { render layout: false }
end

Your execution path attempts two render calls, which gets you a double render error.

Your code should look like something along these lines:

  def create
    @user = User.new(params[:user])
    respond_to do |format|
      if @user.save
        # sign in user here and render response for success
        format.js  { #handle js }
        format.html { #handle html }
      else
        # user was not saved
        format.js  { #handle error }
        format.html { #handle error }
      end
    end
  end

Answer 2

I had the same issue, and bypassed it by overriding Devise::SessionsController, like so:

class SessionsController < Devise::SessionsController
  def new
    self.resource = resource_class.new(sign_in_params)
    clean_up_passwords(resource)
    #yield resource if block_given?
    #respond_with(resource, serialize_options(resource))


    # The rest of your code

    # your redirect
         redirect_to '/'

end

I'm unsure as to whether this has any negative side affects, but it appears to work fine, and also stops it from appending user sign-in data to the URL.