Containr/internal/middleware/middleware.go

package middleware

import (
	"fmt"
	"log"
	"net/http"
	"strings"
	"time"

	"github.com/gin-gonic/gin"
	"github.com/golang-jwt/jwt/v5"
	"github.com/google/uuid"
)

// Logger middleware
func Logger() gin.HandlerFunc {
	return gin.LoggerWithFormatter(func(param gin.LogFormatterParams) string {
		return fmt.Sprintf("%s - [%s] \"%s %s %s %d %s \"%s\" %s\"\n",
			param.ClientIP,
			param.TimeStamp.Format(time.RFC1123),
			param.Method,
			param.Path,
			param.Request.Proto,
			param.StatusCode,
			param.Latency,
			param.Request.UserAgent(),
			param.ErrorMessage,
		)
	})
}

// Recovery middleware
func Recovery() gin.HandlerFunc {
	return gin.Recovery()
}

// RequestID middleware adds a unique request ID to each request
func RequestID() gin.HandlerFunc {
	return func(c *gin.Context) {
		requestID := c.GetHeader("X-Request-ID")
		if requestID == "" {
			requestID = uuid.New().String()
		}
		c.Set("request_id", requestID)
		c.Header("X-Request-ID", requestID)
		c.Next()
	}
}

// Auth middleware for JWT authentication
func Auth(jwtSecret string) 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
		}

		bearerToken := strings.Split(authHeader, " ")
		if len(bearerToken) != 2 || bearerToken[0] != "Bearer" {
			c.JSON(http.StatusUnauthorized, gin.H{"error": "Invalid authorization header format"})
			c.Abort()
			return
		}

		tokenString := bearerToken[1]
		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 []byte(jwtSecret), nil
		})

		if err != nil {
			c.JSON(http.StatusUnauthorized, gin.H{"error": "Invalid token"})
			c.Abort()
			return
		}

		if claims, ok := token.Claims.(jwt.MapClaims); ok && token.Valid {
			c.Set("user_id", claims["user_id"])
			c.Set("email", claims["email"])
			c.Next()
		} else {
			c.JSON(http.StatusUnauthorized, gin.H{"error": "Invalid token claims"})
			c.Abort()
		}
	}
}

// ErrorHandler middleware for consistent error handling
func ErrorHandler() gin.HandlerFunc {
	return func(c *gin.Context) {
		c.Next()

		// Check if there are any errors
		if len(c.Errors) > 0 {
			err := c.Errors.Last()
			log.Printf("Request error: %v", err)

			// Return JSON error response
			c.JSON(http.StatusInternalServerError, gin.H{
				"error": "Internal server error",
				"code":  "INTERNAL_ERROR",
			})
		}
	}
}

// CORSMiddleware for CORS handling
func CORSMiddleware() gin.HandlerFunc {
	return func(c *gin.Context) {
		c.Header("Access-Control-Allow-Origin", "*")
		c.Header("Access-Control-Allow-Credentials", "true")
		c.Header("Access-Control-Allow-Headers", "Content-Type, Content-Length, Accept-Encoding, X-CSRF-Token, Authorization, accept, origin, Cache-Control, X-Requested-With")
		c.Header("Access-Control-Allow-Methods", "POST, OPTIONS, GET, PUT, DELETE")

		if c.Request.Method == "OPTIONS" {
			c.AbortWithStatus(204)
			return
		}

		c.Next()
	}
}