Files
tanabata/backend/internal/handler/middleware.go
T
H1K0 d357ae3156 feat: open file original in a new tab via authenticated direct link
The file viewer's preview is now a real link (target=_blank) to the original,
instead of fetching it into a blob. A navigation can't send the auth header, so
the access token rides in the query — the auth middleware accepts ?access_token=
as a fallback, but only for GET, so a crafted link can't drive a mutation.

GetContent gains an ?inline=1 toggle (Content-Disposition: inline) so the tab
views the original instead of downloading it; download stays the default.

Documented in openapi.yaml; TestMediaQueryTokenAuth covers GET-with-query-token
(200), missing token (401) and query-token rejected on a non-GET (401).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-11 15:40:50 +03:00

67 lines
1.9 KiB
Go

package handler
import (
"net/http"
"strings"
"github.com/gin-gonic/gin"
"tanabata/backend/internal/domain"
"tanabata/backend/internal/service"
)
// AuthMiddleware validates Bearer JWTs and injects user identity into context.
type AuthMiddleware struct {
authSvc *service.AuthService
}
// NewAuthMiddleware creates an AuthMiddleware backed by authSvc.
func NewAuthMiddleware(authSvc *service.AuthService) *AuthMiddleware {
return &AuthMiddleware{authSvc: authSvc}
}
// Handle returns a Gin handler function that enforces authentication.
// On success it calls c.Next(); on failure it aborts with 401 JSON.
func (m *AuthMiddleware) Handle() gin.HandlerFunc {
return func(c *gin.Context) {
token := bearerToken(c)
if token == "" {
c.JSON(http.StatusUnauthorized, errorBody{
Code: domain.ErrUnauthorized.Code(),
Message: "authorization header missing or malformed",
})
c.Abort()
return
}
claims, err := m.authSvc.ValidateAccessToken(c.Request.Context(), token)
if err != nil {
c.JSON(http.StatusUnauthorized, errorBody{
Code: domain.ErrUnauthorized.Code(),
Message: "invalid or expired token",
})
c.Abort()
return
}
ctx := domain.WithUser(c.Request.Context(), claims.UserID, claims.IsAdmin, claims.SessionID)
c.Request = c.Request.WithContext(ctx)
c.Next()
}
}
// bearerToken extracts the access token from the Authorization header. As a
// fallback it accepts an ?access_token= query parameter, but only for GET
// requests — this lets the browser open media (e.g. /files/{id}/content) via a
// plain link/new tab, where it can't send the header, without allowing a crafted
// link to drive a state-changing request.
func bearerToken(c *gin.Context) string {
if raw := c.GetHeader("Authorization"); strings.HasPrefix(raw, "Bearer ") {
return strings.TrimPrefix(raw, "Bearer ")
}
if c.Request.Method == http.MethodGet {
return c.Query("access_token")
}
return ""
}