create_subscription_with_v2.ex

def create_subscription(email, plan_id, payment_method_id) do
  with {:user_lookup, %User{customer_id: nil, name: name} = user} <-
         {:user_lookup, Repo.get_by(User, email: email)},
       {:customer_creation, {:ok, %Stripe.Customer{id: customer_id}}} <-
         {:customer_creation,
          Stripe.Customer.create(%{
            name: name,
            email: email,
            payment_method: payment_method_id,
            invoice_settings: %{
              default_payment_method: payment_method_id
            }
          })},
       {:subscription_creation, {:ok, %Stripe.Subscription{id: subscription_id}}} <-
         {:subscription_creation,
          Stripe.Subscription.create(%{customer: customer_id, items: [%{plan: plan_id}]})},
       {:user_update, {:ok, %User{}}} <-
         {:user_update,
          User.update(user, %{customer_id: customer_id, subscription_id: subscription_id})} do
    {:ok, :subscription_created}
  else
    {:user_lookup, _} ->
      {:error, :user_lookup_error}

    {:customer_creation, _} ->
      {:error, :customer_creation_error}

    {:subscription_creation, _} ->
      {:error, :subscription_creation_error}

    {:user_update, _} ->
      {:error, :user_update_error}

    err ->
      {:error, err}
  end
end