Hi! First, I’d like to thank the Ash team. Ash solves so many problems! I’m planning to incrementally migrate my whole app to it.

I’ve got one problem, though. My app uses schema-based multitenancy and the Process dictionary to store the tenant_id, and default_options/1 to automatically put the right schema prefix for all queries.

defmodule App.Repo do
  use AshPostgres.Repo,
    otp_app: :app

  @tenant_key {__MODULE__, :tenant_id}

  def default_options(_opts) do
    case get_tenant_id() do
      nil -> []
      tenant_id -> [prefix: "tenant_#{tenant_id}"]
    end
  end

  def put_tenant_id(tenant_id) when is_integer(tenant_id) do
    Process.put(@tenant_key, tenant_id)
  end

  def get_tenant_id do
    Process.get(@tenant_key)
  end
end

This is not a problem for the multitenant Ash Resources. But when I try to create global Ash Resources, they are scoped to the current tenant’s schema. I’ve tried something like this:

  postgres do
    repo App.Repo
    table "settings"
    schema "public"
  end

But schema "public" doesn’t seem to translate to a prefix: "public" passed to Ecto that would override the default option. It also creates a new migration with a “public” prefix.

How could I tell Ash to set a prefix for Ecto’s Repo?