Golang Time Notes

The Time value is an empty struct:

type Time struct {}

The zero value of type Time is January 1, year 1, 00:00:00.000000000 UTC.

fmt.Println(time.Time{})
// => 0001-01-01 00:00:00 +0000 UTC

You can ask a time if it is the zero value:

if myTime.IsZero() {
  // do some stuff
}

Creating a new time value

To get the current time:

timeNow := time.Now()

Getting the time in UTC:

timeNow := time.Now().UTC()

To get a time value specifying values:

t := time.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC)

The Date signature is:

func Date(year int, month Month, day, hour, min, sec, nsec int, loc *Location) Time

To parse the time from a formatted string:

t, err := time.Parse(time.RFC3339, "2016-06-24T11:51:23-07:00")

To get the datetime from 36 hours ago:

t := time.Now().UTC().Add(-time.Hour * 36)

... or, from 45 minutes ago using a constant:

const MINUTES_AGO_CUTOFF = 45
t := time.Now().UTC().Add((-1 * MINUTES_AGO_CUTOFF) * time.Minute)

Getting the hours between 2 dates:

time1.Sub(time2).Hours()

... or, days:

time1.Sub(time2).Hours() / 24