goenv.go

package goenv

import (
	"errors"
	"fmt"
	"os"
	"reflect"
	"strings"

	"github.com/joho/godotenv"
)

func Load[T any](s *T) error {
	err := godotenv.Load()
	if err != nil {
		return err
	}

	v := reflect.ValueOf(*s)
	ptr := reflect.ValueOf(s)

	errs := []error{}

	str := ptr.Elem()

	if str.Kind() != reflect.Struct {
		return errors.New("value should be a struct")
	}

	for i := range v.Type().NumField() {
		env := v.Type().Field(i).Tag.Get("env")
		sl := strings.Split(env, ",")

		envName := sl[0]
		val := os.Getenv(envName)

		if isEnvRequired(env) && val == "" {
			errs = append(errs, fmt.Errorf("Env %s is required", envName))
		}

		defaultValue := getEnvDefaultValue(env)
		if val == "" {
			val = defaultValue
		}

		f := str.Field(i)
		if f.IsValid() && f.CanSet() {
			f.SetString(val)
		}
	}

	if len(errs) > 0 {
		return errors.Join(errs...)
	}

	return nil
}

func MustLoad[T any](s *T) {
	err := Load(s)
	if err != nil {
		panic(err)
	}
}