feat: add validator for jwt

backend/internal/auth/jwt.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"os"
 	"strings"
+	"time"
 
 	"gitea.d3m0k1d.ru/d3m0k1d/d3m0k1d.ru/backend/internal/storage"
 	"github.com/gin-gonic/gin"
@@ -14,10 +15,13 @@ var jwtSecret = []byte(os.Getenv("JWT_SECRET"))
 
 func GenerateJWT(user storage.User) (string, error) {
 	token := jwt.NewWithClaims(jwt.SigningMethodHS512, jwt.MapClaims{
-		"id":        user.ID,
-		"email":     user.Email,
-		"login":     user.GithubLogin,
-		"github_id": user.GithubID,
+		"id":         user.ID,
+		"email":      user.Email,
+		"login":      user.GithubLogin,
+		"github_id":  user.GithubID,
+		"avatar_url": user.AvatarURL,
+		"exp":        time.Now().Add(30 * 24 * time.Hour).Unix(), // 30 дней
+		"iat":        time.Now().Unix(),
 	})
 	tokenString, err := token.SignedString(jwtSecret)
 	if err != nil {
@@ -113,3 +117,58 @@ func RequireAdmin() gin.HandlerFunc {
 		c.Next()
 	}
 }
+
+func ValidateJWT(tokenString string) (*storage.User, error) {
+	token, err := jwt.Parse(tokenString, func(token *jwt.Token) (interface{}, error) {
+		if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
+			return nil, fmt.Errorf("unexpected signing method: %v", token.Header["alg"])
+		}
+		return jwtSecret, nil
+	})
+
+	if err != nil || !token.Valid {
+		return nil, err
+	}
+
+	claims, ok := token.Claims.(jwt.MapClaims)
+	if !ok {
+		return nil, fmt.Errorf("invalid claims")
+	}
+
+	if exp, ok := claims["exp"].(float64); ok {
+		if time.Now().Unix() > int64(exp) {
+			return nil, fmt.Errorf("token expired")
+		}
+	}
+	idFloat, ok := claims["id"].(float64)
+	if !ok {
+		return nil, fmt.Errorf("invalid id in token")
+	}
+
+	githubIDFloat, ok := claims["github_id"].(float64)
+	if !ok {
+		return nil, fmt.Errorf("invalid github_id in token")
+	}
+
+	login, ok := claims["login"].(string)
+	if !ok {
+		return nil, fmt.Errorf("invalid login in token")
+	}
+
+	email, ok := claims["email"].(string)
+	if !ok {
+		return nil, fmt.Errorf("invalid email in token")
+	}
+
+	avatarURL, _ := claims["avatar_url"].(string)
+
+	user := &storage.User{
+		ID:          int(idFloat),
+		GithubID:    int(githubIDFloat),
+		GithubLogin: login,
+		Email:       email,
+		AvatarURL:   avatarURL,
+	}
+
+	return user, nil
+}