What implementation of Foo.mega_to_payload/3 do you prefer? Why?

foo.ex

defmodule Foo do
  def mega_to_payload(
    %MyMegaProtobuf{
      c_seq: c_seq,
      call_id: call_id
    },
    timestamp,
    message_id
  ) do
    %{
      c_seq: c_seq,
      call_id: call_id,
      message_id: message_id,
      timestamp: timestamp,
      update_id: DateTime.to_unix(timestamp, :microsecond)
    }
    |> DB.insert_one()
  end

  def mega_to_payload(
    %MyMegaProtobuf{} = mega_struct,
    timestamp,
    message_id
  ) do
    keys_to_store = [
      :c_seq,
      :call_id
    ]

    mega_struct
    |> Map.take(keys_to_store)
    |> Map.merge(%{
      message_id: message_id,
      timestamp: timestamp,
      update_id: DateTime.to_unix(timestamp, :microsecond)
    })
    |> DB.insert_one()
  end
end

my_mega_protobuf.ex

defmodule MyMegaProtobuf do
  @moduledoc """
    This is autogenerated file. Do not change it manually.
  """
  defstruct [
    :c_seq,
    :call_id,
    :recipient_id,
    :sender_id,
    :status
  ]
end