This package offers the ability to parse a string to a time.Duration. It's more strict (specific order and no repetition) than the time.ParseDuration but it offers more options: y (year), w (week) and d(day).

It also has those durations as constants so: duration.Year, duration.Week and duration.Day

go get github.com/xescugc/duration

Parse parses a duration string with the following formats:

• y(year)
• w(week)
• d(day)
• h(hour)
• m(minute)
• s(second)
• ms(millisecond)
• us or µs(microsecond)
• ns(nanosecond).

The order of the string is strict, must be from 'larger' to 'lesser', so '1m1s' is correct but '1s1m' is not, and repetitions are not permitted, '1s1s' is invalid.