I have this plug in my router pipeline to login an user using a magic link:

defmodule CoreWeb.Router.Plugs.LoginWithMagicToken do
  alias Core.Marketplace.Accounts.User

  import Plug.Conn

  def init(opts), do: opts

  def call(%{params: %{"magic_token" => token}, assigns: %{current_user: nil}} = conn, opts) do
    case User.sign_in_with_magic_link(%{token: token}, load: :token) do
      {:ok, user} ->
        uri = Phoenix.Controller.current_path(conn)

        conn
        |> Plug.Conn.delete_session(:return_to)
        |> AshAuthentication.Plug.Helpers.store_authentication_result({:ok, user}) # |> AshAuthentication.Plug.Helpers.store_in_session(user)
        |> Phoenix.Controller.redirect(to: uri)
        |> halt()

      _ ->
        conn
    end
  end

  def call(conn, _opts), do: conn
end

Basically, if the current_user is nil and there is a "magic_token" param in the url, it will try to sign_in with the magic link and then store it in the connection.

The User.sign_in_with_magic_link works fine, it will return the user based on the token. The issue is that I can’t make the user persist in the connection.

AFAIK, the store_authentication_result or store_in_session helper functions should do the trick, but it doesn’t seem to work, it will still have current_user as nil after the redirect.

This was working before, so I’m not sure if it was an Ash Authentication upgrade that broke it or something else.

Also, I think it is important to note that this code is ran in an iframe.