Hello all,
I am casually working on, as a hobbyist project, every now and then, a WordPress read-only Elixir viewer. I am working my way through several dumped WP databases and making Ecto schema modules out of their tables.

I stumbled upon this one today:

mysql> desc wp_wfBlockedIPLog;
+-------------+------------------+------+-----+------------------+-------+
| Field       | Type             | Null | Key | Default          | Extra |
+-------------+------------------+------+-----+------------------+-------+
| IP          | binary(16)       | NO   | PRI |                  |       |
| countryCode | varchar(2)       | NO   |     | NULL             |       |
| blockCount  | int(10) unsigned | NO   |     | 0                |       |
| unixday     | int(10) unsigned | NO   | PRI | NULL             |       |
+-------------+------------------+------+-----+------------------+-------+
4 rows in set (0.01 sec)

Primary question

How can I express a primary key – through the @primary_key attribute, I imagine – for this module?

So far my first try (without the double primary key) is:

defmodule WP.WfBlockedIpLog do
  use Ecto.Schema

  @primary_key {:id, :binary_id, autogenerate: false, source: :IP}
  schema "wp_wfBlockedIPLog" do
    field :block_count, :integer, source: :blockCount
    field :country_code, :string, source: :countryCode
    field :unixday, :integer
    field :date, :date, virtual: true # <- Note this for the secondary question.
  end
end

Example of a loaded Ecto.Schema:

  %WP.WfBlockedIpLog{
    __meta__: #Ecto.Schema.Metadata<:loaded, "wp_wfBlockedIPLog">,
    block_count: 5,
    country_code: "UA",
    date: nil,
    id: "00000000-0000-0000-0000-ffff2573bf43",
    unixday: 17030
  }

The above module gives me a string UUID which I am not very happy with. Is there a way to make the ID a true binary?

Secondary question

I realized after inspecting the dumped WP databases that unixday above is basically a date:

17_030
|> Kernel.*(24*60*60)
|> DateTime.from_unix!()
|> DateTime.to_date()

Is there a way to have the date virtual field above be filled at Repo.get, transparently? Or is there a way to do it at all? What alternative approaches would you recommend?

Thank you.