Files
2025-12-28 13:24:16 +01:00

43 lines
1.2 KiB
Go

package middleware
import (
"net/http"
"strings"
"github.com/gin-gonic/gin"
"github.com/golang-jwt/jwt/v5"
)
// AuthMiddleware validates a JWT token from the Authorization header
func AuthMiddleware(secret string) gin.HandlerFunc {
return func(c *gin.Context) {
auth := c.GetHeader("Authorization")
if auth == "" {
c.AbortWithStatusJSON(http.StatusUnauthorized, gin.H{"error": "missing authorization header"})
return
}
parts := strings.SplitN(auth, " ", 2)
if len(parts) != 2 || strings.ToLower(parts[0]) != "bearer" {
c.AbortWithStatusJSON(http.StatusUnauthorized, gin.H{"error": "invalid authorization header"})
return
}
tokenStr := parts[1]
token, err := jwt.Parse(tokenStr, func(t *jwt.Token) (interface{}, error) {
// ensure signing method is HMAC
if _, ok := t.Method.(*jwt.SigningMethodHMAC); !ok {
return nil, jwt.ErrTokenUnverifiable
}
return []byte(secret), nil
})
if err != nil || !token.Valid {
c.AbortWithStatusJSON(http.StatusUnauthorized, gin.H{"error": "invalid token"})
return
}
// expose token claims to handlers
if claims, ok := token.Claims.(jwt.MapClaims); ok {
c.Set("claims", claims)
}
c.Next()
}
}