gocommon/reflect_config.go

package gocommon

import (
	"crypto/md5"
	"encoding/hex"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"net/url"
	"os"
	"strings"
	"time"

	"repositories.action2quare.com/ayo/gocommon/flagx"
)

var configfileflag = flagx.String("config", "", "")

func configFilePath() string {
	configfilepath := "config.json"
	if configfileflag != nil && len(*configfileflag) > 0 {
		configfilepath = *configfileflag
	}

	// if !strings.HasPrefix(configfilepath, "/") {
	// 	exe, _ := os.Executable()
	// 	configfilepath = path.Join(path.Dir(exe), configfilepath)
	// }

	return configfilepath
}

func ConfigModTime() time.Time {
	fi, err := os.Stat(configFilePath())
	if err == nil {
		return fi.ModTime()
	}
	return time.Time{}
}

func MonitorConfig[T any](onChanged func(newconf *T)) error {
	fi, err := os.Stat(configFilePath())
	if err != nil {
		return err
	}

	go func(modTime time.Time, filepath string) {
		for {
			if fi, err := os.Stat(filepath); err == nil {
				if modTime != fi.ModTime() {
					var next T
					if err := LoadConfig(&next); err == nil {
						fi, _ := os.Stat(filepath)
						modTime = fi.ModTime()

						onChanged(&next)
					}
				}
			}
			time.Sleep(time.Second)
		}
	}(fi.ModTime(), configFilePath())

	return nil
}

var configContents []byte

func splitURL(inputURL string) (string, string, error) {
	parsedURL, err := url.Parse(inputURL)
	if err != nil {
		return "", "", err
	}

	base := fmt.Sprintf("%s://%s", parsedURL.Scheme, parsedURL.Host)
	path := parsedURL.Path

	return base, path, nil
}

func LoadConfig[T any](outptr *T) error {
	configfilepath := configFilePath()
	if len(configContents) == 0 {
		if strings.HasPrefix(configfilepath, "http") {
			// 여기서 다운받음
			_, subpath, err := splitURL(configfilepath)
			if err != nil {
				return err
			}

			h := md5.New()
			h.Write([]byte(subpath))
			at := hex.EncodeToString(h.Sum(nil))

			req, _ := http.NewRequest("GET", configfilepath, nil)
			req.Header.Add("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36 Edg/111.0.1661.51")
			req.Header.Add("As-X-UrlHash", at)

			resp, err := http.DefaultClient.Do(req)
			if err != nil {
				return err
			}
			defer resp.Body.Close()
			configContents, err = io.ReadAll(resp.Body)
			if err != nil {
				return err
			}
		} else {
			content, _ := os.ReadFile(configfilepath)
			if len(content) == 0 {
				content = []byte("{}")
			}

			configContents = content
		}
	}

	return json.Unmarshal([]byte(os.Expand(string(configContents), func(in string) string {
		envval := os.Getenv(in)
		if len(envval) == 0 {
			return "$" + in
		}
		return envval
	})), outptr)
}

type StorageAddr struct {
	Mongo string
	Redis map[string]string
}

type RegionStorageConfig struct {
	RegionStorage map[string]StorageAddr `json:"region_storage"`
}