passed/config/config.go

package config

import (
	"log"
	"os"
	"strconv"
)

func Env(name string, out any, def string) {
	raw := os.Getenv(name)
	if raw == "" {
		raw = def
		log.Printf("No \"%s\" provided, defaulting to \"%s\".", name, def)
	}

	switch value := out.(type) {
	case *int:
		i, err := strconv.ParseInt(raw, 10, 64)
		if err != nil {
			log.Printf("\"%s\" is not a number (\"%s\").", name, raw)
			return
		}

		*value = int(i)

	case *bool:
		switch raw {
		case "true", "TRUE", "1":
			*value = true
		case "false", "FALSE", "0":
			*value = false
		}

	case *string:
		*value = raw
	}
}