Rails 5 … No flash notice message

Question

I'm following Michael Hartl's Rails 5 Tutorial online. I'm on the Toy App portion. I have a simple User scaffold in place. When I create a new user, I'm redirected to the show template, but the flash notice message content isn't being displayed.

The controller code is as follows:

def create
@user = User.new(user_params)

respond_to do |format|
  if @user.save
    format.html { redirect_to @user, notice: 'User was successfully created.' }
  end
end
end

The view code is here:

<p id="notice"><%= notice %></p>

The P element is being created and receiving the appropriate CSS styles, but the message isn't being passed to it.

Basically, I'm getting this for my output:

<p id="notice"></p>

I added this to the view:

<% if flash[:notice].blank? %>
  <h1> flash notice is blank </h1>
<% end %>

...and I am getting the message that the flash notice is blank.

I'm on Rails 5.0.0.1 and Ruby 1.3.2. Thank you.

Answer 1

Okay, so this has to do with an edit that I made to the application_controller.rb file. The first time I tried to create a new user, I received an error:

ActionController::InvalidAuthenticityToken in UsersController#create

To remedy this, on the second line of my application_controller.rb file, I changed this:

protect_from_forgery with: :exception

to this:

protect_from_forgery with: :null_session

I guess this 'nullified' my session, so to speak, so certain session variables aren't getting passed, including flash messages?

Anyway, this change allowed me to create new users fine, but then I discovered that the flash notice messages weren't being displayed.

To remedy that, I changed :null_session back to :exception on the application_controller file, and then I added a new line to my users_controller.rb file that skips verification of an authentication token for new users. This probably isn't suitable for production, but for the sake of moving through the tutorial, it's a start:

class UsersController < ApplicationController
  skip_before_action :verify_authenticity_token