in log/zaplogger.go [205:236]
func DefaultTimeFormat(t time.Time) []byte {
t = t.Local()
year, month, day := t.Date()
hour, minute, second := t.Clock()
micros := t.Nanosecond() / 1000
buf := make([]byte, 23)
buf[0] = byte((year/1000)%10) + '0'
buf[1] = byte((year/100)%10) + '0'
buf[2] = byte((year/10)%10) + '0'
buf[3] = byte(year%10) + '0'
buf[4] = '-'
buf[5] = byte((month)/10) + '0'
buf[6] = byte((month)%10) + '0'
buf[7] = '-'
buf[8] = byte((day)/10) + '0'
buf[9] = byte((day)%10) + '0'
buf[10] = ' '
buf[11] = byte((hour)/10) + '0'
buf[12] = byte((hour)%10) + '0'
buf[13] = ':'
buf[14] = byte((minute)/10) + '0'
buf[15] = byte((minute)%10) + '0'
buf[16] = ':'
buf[17] = byte((second)/10) + '0'
buf[18] = byte((second)%10) + '0'
buf[19] = '.'
buf[20] = byte((micros/100000)%10) + '0'
buf[21] = byte((micros/10000)%10) + '0'
buf[22] = byte((micros/1000)%10) + '0'
return buf
}