First setup of a go server

middleware/auth.go

@@ -0,0 +1,50 @@
+package middleware
+
+import (
+	"net/http"
+	"strings"
+
+	"github.com/gin-gonic/gin"
+	"github.com/golang-jwt/jwt/v5"
+)
+
+var jwtSecret = []byte("your-secret-key") // Should match the one in handlers/auth.go
+
+func AuthMiddleware() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		authHeader := c.GetHeader("Authorization")
+		if authHeader == "" {
+			c.JSON(http.StatusUnauthorized, gin.H{"error": "Authorization header required"})
+			c.Abort()
+			return
+		}
+
+		// Extract token from "Bearer <token>" format
+		tokenString := strings.TrimPrefix(authHeader, "Bearer ")
+		if tokenString == authHeader {
+			c.JSON(http.StatusUnauthorized, gin.H{"error": "Invalid token format"})
+			c.Abort()
+			return
+		}
+
+		// Parse and validate token
+		token, err := jwt.Parse(tokenString, func(token *jwt.Token) (interface{}, error) {
+			return jwtSecret, nil
+		})
+
+		if err != nil || !token.Valid {
+			c.JSON(http.StatusUnauthorized, gin.H{"error": "Invalid token"})
+			c.Abort()
+			return
+		}
+
+		// Extract claims
+		if claims, ok := token.Claims.(jwt.MapClaims); ok {
+			if userID, ok := claims["user_id"].(float64); ok {
+				c.Set("user_id", uint(userID))
+			}
+		}
+
+		c.Next()
+	}
+}