Started Authentication System

auth/jwt.go

@@ -0,0 +1,45 @@
+package auth
+
+import (
+	"os"
+	"time"
+
+	"github.com/golang-jwt/jwt/v5"
+)
+
+type Claims struct {
+	UserID string `json:"user_id"`
+	Role   string `json:"role"`
+	jwt.RegisteredClaims
+}
+
+var secret = os.Getenv("SHAP_JWT_SECRET")
+
+func GenerateJWT(userID, role string, secret []byte) (string, error) {
+	claims := Claims{
+		UserID: userID,
+		Role:   role,
+		RegisteredClaims: jwt.RegisteredClaims{
+			ExpiresAt: jwt.NewNumericDate(time.Now().Add(15 * time.Minute)),
+			IssuedAt:  jwt.NewNumericDate(time.Now()),
+		},
+	}
+
+	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
+	return token.SignedString(secret)
+}
+func ValidateJWT(tokenStr string, secret []byte) (*Claims, error) {
+	token, err := jwt.ParseWithClaims(tokenStr, &Claims{}, func(token *jwt.Token) (interface{}, error) {
+		return secret, nil
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	claims, ok := token.Claims.(*Claims)
+	if !ok || !token.Valid {
+		return nil, err
+	}
+
+	return claims, nil
+}

auth/middleware.go

@@ -0,0 +1,48 @@
+package auth
+
+import (
+	"context"
+	"net/http"
+	"strings"
+)
+
+type contextKey string
+
+const UserContextKey contextKey = contextKey("user")
+
+func AuthMiddleware(secret []byte) func(http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+
+			authHeader := r.Header.Get("Authorization")
+			if authHeader == "" {
+				http.Error(w, "Missing token", http.StatusUnauthorized)
+				return
+			}
+
+			tokenStr := strings.TrimPrefix(authHeader, "Bearer ")
+
+			claims, err := ValidateJWT(tokenStr, secret)
+			if err != nil {
+				http.Error(w, "Invalid token", http.StatusUnauthorized)
+				return
+			}
+
+			ctx := context.WithValue(r.Context(), UserContextKey, claims)
+			next.ServeHTTP(w, r.WithContext(ctx))
+
+		})
+	}
+}
+func RequireRole(role string) func(http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			claims := r.Context().Value(UserContextKey).(*Claims)
+			if claims.Role != role {
+				http.Error(w, "Forbidden", http.StatusForbidden)
+				return
+			}
+			next.ServeHTTP(w, r)
+		})
+	}
+}

auth/password.go

@@ -0,0 +1,12 @@
+package auth
+
+import "golang.org/x/crypto/bcrypt"
+
+func HashPassword(password string) (string, error) {
+	bytes, err := bcrypt.GenerateFromPassword([]byte(password), 14)
+	return string(bytes), err
+}
+func CheckPasswordHash(password, hash string) bool {
+	err := bcrypt.CompareHashAndPassword([]byte(hash), []byte(password))
+	return err == nil
+}