initial commit

pkg/jwt/token_generator.go

@@ -0,0 +1,121 @@
+package jwt
+
+import (
+	"context"
+	"errors"
+	"time"
+
+	"github.com/lestrrat-go/jwx/v3/jwa"
+	"github.com/lestrrat-go/jwx/v3/jwt"
+)
+
+var (
+	ErrTokenVerificationFailed = errors.New("token verification failed")
+)
+
+type tokenService struct {
+	secretKey              []byte
+	accessTokenExpiration  time.Duration
+	refreshTokenExpiration time.Duration
+}
+
+func New(secret string, ate, rfe time.Duration) TokenService {
+	secretKey := []byte(secret)
+	return &tokenService{
+		secretKey:              secretKey,
+		accessTokenExpiration:  ate,
+		refreshTokenExpiration: rfe,
+	}
+}
+
+func (ts tokenService) GenerateAccessRefreshTokenPair(
+	ctx context.Context,
+	tokenData *TokenData,
+) (*AccessRefreshTokenPair, error) {
+	accessTokenExp := time.Now().Add(ts.accessTokenExpiration)
+	generateAccessJwt, err := ts.generateJwt(accessTokenExp, tokenData.Sub, "alinme-web")
+	if err != nil {
+		return nil, err
+	}
+
+	refreshTokenExp := time.Now().Add(ts.refreshTokenExpiration)
+	generateRefreshJwt, err := ts.generateJwt(refreshTokenExp, tokenData.Sub, "alinme-web")
+	if err != nil {
+		return nil, err
+	}
+
+	return &AccessRefreshTokenPair{
+		AccessToken:           generateAccessJwt,
+		AccessTokenExpiresAt:  accessTokenExp,
+		RefreshToken:          generateRefreshJwt,
+		RefreshTokenExpiresAt: refreshTokenExp,
+	}, nil
+}
+
+func (ts tokenService) generateJwt(exp time.Time, sub string, aud string) (string, error) {
+	t, err := jwt.NewBuilder().
+		Subject(sub).
+		IssuedAt(time.Now()).
+		Issuer("alinme-server").
+		Audience([]string{aud}).
+		Expiration(exp).
+		Build()
+
+	if err != nil {
+		return "", err
+	}
+	signed, err := jwt.Sign(t, jwt.WithKey(jwa.HS256(), ts.secretKey))
+	if err != nil {
+		return "", err
+	}
+	return string(signed), nil
+}
+
+func (ts tokenService) VerifyToken(ctx context.Context, accessToken string) (*TokenPayload, error) {
+	parsed, err := jwt.Parse([]byte(accessToken), jwt.WithKey(jwa.HS256(), ts.secretKey))
+	if err != nil {
+		return nil, ErrTokenVerificationFailed
+	}
+
+	sub, ok := parsed.Subject()
+	if !ok {
+		return nil, ErrTokenVerificationFailed
+	}
+
+	aud, ok := parsed.Audience()
+	if !ok {
+		return nil, ErrTokenVerificationFailed
+	}
+
+	iat, ok := parsed.IssuedAt()
+	if !ok {
+		return nil, ErrTokenVerificationFailed
+	}
+
+	exp, ok := parsed.Expiration()
+	if !ok {
+		return nil, ErrTokenVerificationFailed
+	}
+
+	iss, ok := parsed.Issuer()
+	if !ok {
+		return nil, ErrTokenVerificationFailed
+	}
+
+	return &TokenPayload{
+		Sub: sub,
+		Aud: aud,
+		Iat: iat,
+		Exp: exp,
+		Iss: iss,
+	}, nil
+}
+
+func (ts tokenService) GenerateToken(ctx context.Context, input *GenerateTokenInput) (string, error) {
+	generateJwt, err := ts.generateJwt(time.Now().Add(time.Minute*5), input.Sub, input.Aud)
+	if err != nil {
+		return "", err
+	}
+
+	return generateJwt, nil
+}