在Devise中注册后尝试自动登录并将用户重定向到特定路径时出现双重渲染错误

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.