calc-date.go

package main

import (
	"fmt"
	"time"
)

// local time calculation
func main() {
	currentTime := time.Now()
	zone, offset := currentTime.Zone()
	offset /= 3600
	fmt.Printf("current timezone %v, offset as hour %v\n", zone, offset)

	dateFormat := "2006-01-02Z07"

	dateStartInput := "2021-09-01"
	dateEndInput := "2021-09-01"

	dateStartAsLocal := fmt.Sprintf("%s%+03d", dateStartInput, offset)
	dateEndAsLocal := fmt.Sprintf("%s%+03d", dateEndInput, offset)

	fmt.Println("dateStartAsLocal", dateStartAsLocal)
	fmt.Println("dateEndAsLocal", dateEndAsLocal)

	start, _ := time.Parse(dateFormat, dateStartAsLocal)
	end, _ := time.Parse(dateFormat, dateEndAsLocal)
	end = end.Add(24 * time.Hour)

	fmt.Println("start:", start.Format(time.RFC3339))
	fmt.Println("end:", end.Format(time.RFC3339))

	fmt.Println(start, end)
	fmt.Println(time.Now().After(start))
	fmt.Println(time.Now().Before(end))
}