dynamic worker_spec definition

lib/pool_toy/application.ex

@@ -3,7 +3,7 @@ defmodule PoolToy.Application do

  def start(_type, _args) do
    children = [
      {PoolToy.PoolSup, [name: :poolio, size: 3]}
      {PoolToy.PoolSup, [name: :poolio, worker_spec: Doubler, size: 3]}
    ]

    opts = [strategy: :one_for_one]

lib/pool_toy/pool_man.ex

@@ -3,9 +3,9 @@ defmodule PoolToy.PoolMan do

  defmodule State do
    defstruct [
      :name, :size, :pool_sup,
      :name, :size, :worker_spec, :pool_sup,
      :monitors, :worker_sup,
      worker_spec: Doubler, workers: []
      workers: []
    ]
  end

@@ -44,6 +44,10 @@ defmodule PoolToy.PoolMan do
    init(rest, %{state | pool_sup: pid})
  end

  defp init([{:worker_spec, spec} | rest], %State{} = state) do
    init(rest, %{state | worker_spec: spec})
  end

  defp init([{:pool_sup, _} | _], _state) do
    {:stop, {:invalid_args, {:pool_sup, "must be provided"}}}
  end
@@ -56,6 +60,10 @@ defmodule PoolToy.PoolMan do
    {:stop, {:missing_args, {:size, "positive integer `size` is required"}}}
  end

  defp init([], %State{worker_spec: nil}) do
    {:stop, {:missing_args, {:worker_spec, "child spec `worker_spec` is required"}}}
  end

  defp init([], %State{name: _, size: _} = state) do
    Process.flag(:trap_exit, true)
    send(self(), :start_worker_sup)