Ash.Error.Forbidden.Policy - how to handle: warning Unhandled error in form submission

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1

Hello developers. I hope you are all well. I have been writing some Ash Policies recently and things have been quite good. However as I was doing form submissions using AshPhoenix, I got this error while trying to perform a create action with a user that is not authorized to do so. Is there a way I can handle this error, probably catch it?

This is what i have done :

      {:ok, region} ->
        notify_parent({:saved, region})

        socket =
          socket
          |> put_flash(:info, "Region #{socket.assigns.form.source.type}d successfully")
          |> push_patch(to: socket.assigns.patch)

        {:noreply, socket}

      {:error, form} ->
        dbg(form)
        errors = form.source.source.errors
        Ash.Error.Forbidden.Policy.report(errors)

        {:noreply,
         socket
         |> put_flash(:error, "You are not authorized to perform this action")
         |> push_patch(to: socket.assigns.patch)}

The outcome:

warning] Unhandled error in form submission for Marketingbsm.Outlet.Region.new

This error was unhandled because Ash.Error.Forbidden.Policy does not implement the `AshPhoenix.FormData.Error` protocol.

** (Ash.Error.Forbidden.Policy) Bread Crumbs:
  > Error returned from: Marketingbsm.Outlet.Region.new


forbidden
2

You can implement the protocol from the error message (AshPhoenix.FormData.Error) for that error, or you can use the transform_errors option to turn it into an error that you want to render:
https://hexdocs.pm/ash_phoenix/AshPhoenix.Form.html#for_action/3