seeds.exs

defmodule BeExercise.DatabaseSeeder do
  alias BeExercise.Repo
  alias BeExercise.Accounts
  alias BeExercise.Accounts.User
  alias BeExercise.Finances
  alias Faker.{Person, Internet}
  alias Ecto.Multi

  @currencies Finances.get_current_known_currencies()

  def insert_user do
    generate_user()
    |> Accounts.create_user()
  end

  def drop do
    Repo.delete_all(User)
  end

  def insert_user_multi() do
    Multi.new()
    |> Multi.insert(:user, User.changeset(%User{}, generate_user()))
    |> Repo.transaction()
  end

  defp generate_user() do
    %{
      name: Person.first_name(),
      email: Internet.email(),
      salaries: [generate_salary(), generate_salary(true)] |> Enum.shuffle()
    }
  end

  defp generate_salary(random_active \\ false) do
    active = if random_active, do: Enum.random([true, false]), else: false

    %{
      currency: Enum.random(@currencies),
      amount: Enum.random(0..300_000) |> Decimal.new(),
      active: active
    }
  end
end

BeExercise.DatabaseSeeder.drop()

Benchee.run(%{
  "original" => fn ->
    1..100_000
    |> Enum.each(fn _ ->
      BeExercise.DatabaseSeeder.insert_user()
    end)
  end,
  "improved.task_async_stream" => fn ->
    1..100_000
    |> Task.async_stream(fn _ ->
      BeExercise.DatabaseSeeder.insert_user()
    end)
    |> Stream.run()
  end,
  "improved.task_async_stream_multi" => fn ->
    1..100_000
    |> Task.async_stream(fn _ ->
      BeExercise.DatabaseSeeder.insert_user_multi()
    end)
    |> Stream.run()
  end
})