[day-05] preload training alongside user

Preload training and exercises when fetching an user and expose this
information in graphql.

lib/wabanex/users/get.ex

@@ -1,5 +1,7 @@
 defmodule Wabanex.Users.Get do
-  alias Wabanex.{Repo, User}
+  import Ecto.Query
+
+  alias Wabanex.{Repo, Training, User}
 
   def call(id) do
     id
@@ -14,7 +16,18 @@ defmodule Wabanex.Users.Get do
     |> Repo.get(uuid)
     |> case do
       nil -> {:error, "User not found"}
-      user -> {:ok, user}
+      user -> {:ok, load_training(user)}
     end
   end
+
+  defp load_training(%User{} = user) do
+    today = Date.utc_today()
+
+    query =
+      from(t in Training,
+        where: ^today >= t.start_date and ^today <= t.end_date
+      )
+
+    Repo.preload(user, trainings: {first(query, :inserted_at), :exercises})
+  end
 end

lib/wabanex_web/schema/types/user.ex

@@ -6,6 +6,7 @@ defmodule WabanexWeb.Schema.Types.User do
     field :id, non_null(:uuid4)
     field :name, non_null(:string)
     field :email, non_null(:string)
+    field :trainings, list_of(:training)
   end
 
   input_object :create_user_input do