I have a minimal Ash, PostgreSQL and Phoenix setup in which I do a

mix phx.gen.html Shop Product products name:string price:float --no-context

Obviously the controller doesn’t work out of the box. With some minor changes it works for
index, show and delete.

lib/app_web/controllers/product_controller.ex:

defmodule AppWeb.ProductController do
  use AppWeb, :controller

  # alias App.Shop
  alias App.Shop.Product

  def index(conn, _params) do
    products = Product.read!()
    render(conn, :index, products: products)
  end

  # def new(conn, _params) do
  #   changeset = Shop.change_product(%Product{})
  #   render(conn, :new, changeset: changeset)
  # end

  # def create(conn, %{"product" => product_params}) do
  #   case Shop.create_product(product_params) do
  #     {:ok, product} ->
  #       conn
  #       |> put_flash(:info, "Product created successfully.")
  #       |> redirect(to: ~p"/products/#{product}")

  #     {:error, %Ecto.Changeset{} = changeset} ->
  #       render(conn, :new, changeset: changeset)
  #   end
  # end

  def show(conn, %{"id" => id}) do
    product = Product.by_id!(id)
    render(conn, :show, product: product)
  end

  # def edit(conn, %{"id" => id}) do
  #   product = Shop.get_product!(id)
  #   changeset = Shop.change_product(product)
  #   render(conn, :edit, product: product, changeset: changeset)
  # end

  # def update(conn, %{"id" => id, "product" => product_params}) do
  #  product = Product.by_id!(id)
  #
  # case Product.update(product, product_params) do
  #  {:ok, product} ->
  #     conn
  #     |> put_flash(:info, "Product updated successfully.")
  #     |> redirect(to: ~p"/products/#{product}")

  #   {:error, %Ecto.Changeset{} = changeset} ->
  #     render(conn, :edit, product: product, changeset: changeset)
  # end
  #end

  def delete(conn, %{"id" => id}) do
    product = Product.by_id!(id)
    :ok = Product.destroy(product)

    conn
    |> put_flash(:info, "Product deleted successfully.")
    |> redirect(to: ~p"/products")
  end
end

Is it possible to change the other functions (how?) so that I don’t have to change the forms or do I always have to change the forms too?

For context: