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postgresqldatetimeelixirecto

Check if "now()" and timestamp from a db aren't different than 3 days

I'm using Phoenix and Ecto. I need to check if a difference between "now()" and a certain date less than 3 days. Exactly I'm trying this:

    {diff_days, {_, _, _}} = Ecto.DateTime.to_erl(my_user.signed_up_at) |> :calendar.time_difference(:calendar.universal_time)
    if diff_days <= 3 do
      # good to go
      # ....
    end

However, this won't for a date older than 3 days and 1 minute, right?

What's the univeral way to check if it's not more but 3 days or 72 hours?

In my database signed_up_at is of type timestamp without timezone

Solution

  • Use DateTime.diff/3:

    three_days_in_seconds = 3 * 24 * 60 * 60
case DateTime.diff(DateTime.utc_now, my_user.signed_up_at, :second) do
  good when good < three_days_in_seconds ->
    # good to go
  _ ->
    # skip
end

    Please note, that :second is a default value for the third argument in a call to DateTime.diff/3 and might be omitted.