Programming Phoenix LiveView: Change @current_user to @current_scope.user (p53)

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1

In the current version B12, page 53 (and on), a lot of references to @current_user are no longer valid as even Phoenix LiveView 1.8 guidelines state that this has changed. From AGENTS.md file:

<!-- phoenix-gen-auth-start -->
## Authentication

- **Always** handle authentication flow at the router level with proper redirects
- **Always** be mindful of where to place routes. `phx.gen.auth` creates multiple router plugs and `live_session` scopes:
  - A plug `:fetch_current_user` that is included in the default browser pipeline
  - A plug `:require_authenticated_user` that redirects to the log in page when the user is not authenticated
  - A `live_session :current_user` scope - For routes that need the current user but don't require authentication, similar to `:fetch_current_user`
  - A `live_session :require_authenticated_user` scope - For routes that require authentication, similar to the plug with the same name
  - In both cases, a `@current_scope` is assigned to the Plug connection and LiveView socket
  - A plug `redirect_if_user_is_authenticated` that redirects to a default path in case the user is authenticated - useful for a registration page that should only be shown to unauthenticated users
- **Always let the user know in which router scopes, `live_session`, and pipeline you are placing the route, AND SAY WHY**
- `phx.gen.auth` assigns the `current_scope` assign - it **does not assign a `current_user` assign**.
- To derive/access `current_user`, **always use the `current_scope.user` assign**, never use **`@current_user`** in templates or LiveViews

Please update your examples because I would think a lot of people might get lost (I did, had to fix this to make it work)

2

Additional context: You can find the reason why these changes were made from the generated code at user_auth.exas reflected below:

def on_mount(:require_authenticated, _params, session, socket) do
    socket = mount_current_scope(socket, session)

    if socket.assigns.current_scope && socket.assigns.current_scope.user do
      {:cont, socket}
    else
      socket =
        socket
        |> Phoenix.LiveView.put_flash(:error, "You must log in to access this page.")
        |> Phoenix.LiveView.redirect(to: ~p"/users/log-in")

      {:halt, socket}
    end
  end