rocket_date_time.ex

defmodule Rocket.DateTime do
  def type, do: :datetime

  # Provide our own casting rules.
  def cast(string) when is_binary(string) do
    # Try to parse different formats here
  end

  # Datetime itself should also be valid
  def cast(%Ecto.DateTime{} = datetime) do
    {:ok, datetime}
  end

  # Everything else needs to be a failure though
  def cast(_), do: :error

  # Datetimes are never considered blank
  def blank?(_), do: false

  # When loading data from the database, we need to
  # convert the Ecto type to our type:
  def load({{year, month, day}, {hour, min, sec}}) do
    {:ok, %Ecto.DateTime{year: year, month: month, day: day,
                         hour: hour, min: min, sec: sec}}
  end

  # When dumping data to the database, we need to convert
  # our type back to Ecto.DateTime one:
  def dump(%Ecto.DateTime{} = dt) do
    {:ok, {{dt.year, dt.month, dt.day}, {dt.hour, dt.min, dt.sec}}}
  end

  def dump(_), do: :error
end