check file exists

internal/photos/api/file.go

@@ -143,3 +143,23 @@ func (s *Service) FileCreateChunk(c *gin.Context) {
 		"checksum": chunk.Sum,
 	})
 }
+
+func (s *Service) FileExists(c *gin.Context) {
+	checksum := c.Param("checksum")
+	if len(checksum) != 40 {
+		s.Error(c, http.StatusBadRequest, photoserrors.ErrStoreBadChecksum)
+		return
+	}
+
+	var fileExists int64
+	if err := s.DB.Model(&models.File{}).Where("checksum = ?", checksum).Count(&fileExists).Error; err != nil {
+		s.Error(c, http.StatusInternalServerError, err)
+		return
+	}
+
+	if fileExists > 0 {
+		c.Status(http.StatusOK)
+	} else {
+		c.Status(http.StatusNotFound)
+	}
+}

internal/photos/api/main.go

@@ -61,6 +61,7 @@ func (s *Service) SetupRoutes() {
 	album.Use(s.RequireSession)
 	album.POST("", s.FileCreate)
 	album.POST("/chunk", s.FileCreateChunk)
+	album.HEAD("/:checksum", s.FileExists)
 
 	s.Gin.NoRoute(func(c *gin.Context) {
 		s.Error(c, http.StatusNotFound, photoserrors.ErrReqNotFound)