schedtxt_auth/internal/utility/token.go

package utility

import (
	"fmt"
	"time"

	"github.com/google/uuid"
	"github.com/golang-jwt/jwt/v5"

	"git.kundeng.us/phoenix/textsender-auth/internal/config"
	"git.kundeng.us/phoenix/textsender-models/pkg/token"
	"git.kundeng.us/phoenix/textsender-models/pkg/user"
)

const ROLE_TYPE = "regular"
const TOKEN_TYPE = "Bearer"

type TokenGenerator struct {
	SecretKey []byte
	hourOffset time.Duration
}

func (t *TokenGenerator) SetSecretKey(secretKey string) {
	t.SecretKey = []byte(secretKey)
}

func (t *TokenGenerator) SetHourOffset(offset time.Duration) error {
	if offset < 48 {
		t.hourOffset = offset
		return nil
	} else {
		return fmt.Errorf("No change")
	}
}

func (t *TokenGenerator) GenerateToken(usr any) (*token.Login, error) {
	issuedAt := time.Now()
	if t.hourOffset == 0 {
		t.hourOffset = 4
	}

	expirationTime := time.Now().Add(t.hourOffset * time.Hour)

	if claims, err := t.generateClaims(usr, TOKEN_TYPE, issuedAt, expirationTime); err != nil {
		return nil, fmt.Errorf("Error generating claims: %v", err)
	} else {
		myToken := jwt.NewWithClaims(jwt.SigningMethodHS256, *claims)
		if tokenString, err := myToken.SignedString(t.SecretKey); err != nil {
			return nil, err
		} else {
			return &token.Login{AccessToken: tokenString, TokenType: TOKEN_TYPE, ExpiresIn: expirationTime.Unix()}, nil
		}
	}
}

func (t *TokenGenerator) generateClaims(usr any, role string, issuedAt time.Time, expiredAt time.Time) (*token.Claims, error) {
	var id uuid.UUID
	switch val := usr.(type) {
	case user.User:
		id = val.Id
	case *user.User:
		id = val.Id
	case user.ServiceUser:
		id = val.Id
	case *user.ServiceUser:
		id = val.Id
	default:
		return nil, fmt.Errorf("Invalid type")
	}

	return &token.Claims{
		UserId: id,
		Role:   role,
		RegisteredClaims: jwt.RegisteredClaims{
			Issuer:    config.App_Name,
			ExpiresAt: jwt.NewNumericDate(expiredAt),
			IssuedAt:  jwt.NewNumericDate(issuedAt),
		},
	}, nil
}