Jason.Encoder ecto example, removing __meta__ and %Ecto.Association.NotLoaded{}

jason_encoder_example.ex

defimpl Jason.Encoder, for: [Example.Module1, Example.Module2] do
 def encode(value, opts) do

    value
    |> process_for_json
    |> Jason.Encode.map(opts)
  end

  def remove_unloaded({_field, %Ecto.Association.NotLoaded{}}, accum), do: accum

  def remove_unloaded({key, %_{__meta__: _} = data_map}, accum) do
    accum |> Keyword.put(key, process_for_json(data_map))
  end

  def remove_unloaded(field, accum), do: accum ++ [field]

  def process_for_json(data) do
    data
    |> Map.from_struct()
    |> Map.delete(:__meta__)
    |> Enum.into([])
    |> Enum.reduce([], &remove_unloaded/2)
    |> Enum.into(%{})
  end
end