isHoliday.go

package main

import (
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"time"
)

func todayDate() time.Time {
	t := time.Now().Local()
	return time.Date(t.Year(), t.Month(), t.Day(), 0, 0, 0, 0, t.Location())
}

var httpClient = http.Client{
	Timeout: 10 * time.Second,
}

func isHoliday() (bool, error) {
	today := todayDate()
	yymmdd := fmt.Sprintf("%04d-%02d-%02d", today.Year(), today.Month(), today.Day())
	url := fmt.Sprintf("https://timor.tech/api/holiday/info/%v", yymmdd)
	req, err := http.NewRequest("GET", url, nil)
	if err != nil {
		return false, err
	}
	req.Header.Set("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36")

	resp, err := httpClient.Do(req)
	if err != nil {
		return false, fmt.Errorf("GET %v: %w", url, err)
	}

	defer resp.Body.Close()
	data, _ := io.ReadAll(resp.Body)
	if resp.StatusCode/100 != 2 {
		return false, fmt.Errorf("GET %v: %v: %v", url, resp.StatusCode, string(data))
	}

	m := make(map[string]interface{})
	if err := json.Unmarshal(data, &m); err != nil {
		return false, fmt.Errorf("holiday: unmarshal JSON response: %w", err)
	}
	if m["code"].(float64) != 0 {
		return false, fmt.Errorf("GET %v: code is %v", url, m["code"])
	}

	if m["holiday"] != nil {
		h := m["holiday"].(map[string]interface{})
		v, ok := h["holiday"]
		return ok && v.(bool), nil
	}
	return false, nil
}

func main() {
	is, err := isHoliday()
	fmt.Printf("%v %v\n", is, err)
}