Login (#6)

Reviewed-on: phoenix/textsender-auth#6
Co-authored-by: phoenix <kundeng00@pm.me>
Co-committed-by: phoenix <kundeng00@pm.me>

internal/utility/token.go

@@ -0,0 +1,40 @@
+package utility
+
+import (
+	"time"
+
+	"github.com/golang-jwt/jwt/v5"
+
+	"git.kundeng.us/phoenix/textsender-auth/internal/model"
+)
+
+type TokenGenerator struct {
+	SecretKey []byte
+}
+
+func (t *TokenGenerator) SetSecretKey(secretKey string) {
+	t.SecretKey = []byte(secretKey)
+}
+
+func (t *TokenGenerator) GenerateToken(user model.User) (*model.Login, error) {
+	claims := t.generateClaims(user, "regular")
+
+	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
+	if tokenString, err := token.SignedString(t.SecretKey); err != nil {
+		return nil, err
+	} else {
+		return &model.Login{AccessToken: tokenString}, nil
+	}
+}
+
+func (t *TokenGenerator) generateClaims(user model.User, role string) model.Claims {
+	return model.Claims{
+		UserId: user.Id.String(),
+		Role:   role,
+		RegisteredClaims: jwt.RegisteredClaims{
+			Issuer:    "textsender-auth",
+			ExpiresAt: jwt.NewNumericDate(time.Now().Add(24 * time.Hour)),
+			IssuedAt:  jwt.NewNumericDate(time.Now()),
+		},
+	}
+}