feat(one-time-downloads): add expiry and retry configuration

Introduce new environment variables to control the behavior of one-time download boxes:
- `WARPBOX_ONE_TIME_DOWNLOAD_EXPIRY_SECONDS`: Sets the lifetime of a one-time box after uploads are complete.
- `WARPBOX_ONE_TIME_DOWNLOAD_RETRY_ON_FAILURE`: Determines whether a box remains available if the ZIP creation or transfer fails.

To support these settings, the ZIP delivery process was refactored to use a temporary file. This ensures that a one-time box is only marked as consumed after the file has been successfully transferred to the client, preventing data loss on network interruptions.

Additionally, added a `DecorateFiles` helper in the box store to reduce code duplication.

lib/server/handlers.go

@@ -55,6 +55,9 @@ func (app *App) handleShowBox(ctx *gin.Context) {
 		ctx.String(http.StatusNotFound, "Box not found")
 		return
 	}
+	if hasManifest && manifest.OneTimeDownload {
+		files = stripOneTimeThumbnailState(files)
+	}
 
 	downloadAll := "/box/" + boxID + "/download"
 	if !app.config.ZipDownloadsEnabled || hasManifest && manifest.DisableZip {
@@ -148,15 +151,24 @@ func (app *App) handleBoxStatus(ctx *gin.Context) {
 		return
 	}
 
-	manifest, _, ok := app.authorizeBoxRequest(ctx, boxID, false)
+	manifest, hasManifest, ok := app.authorizeBoxRequest(ctx, boxID, false)
 	if !ok {
 		return
 	}
 
-	files, err := boxstore.ListFiles(boxID)
-	if err != nil {
-		ctx.JSON(http.StatusNotFound, gin.H{"error": "Box not found"})
-		return
+	var files []models.BoxFile
+	if hasManifest && manifestFilesReady(manifest.Files) {
+		files = boxstore.DecorateFiles(boxID, manifest.Files)
+	} else {
+		var err error
+		files, err = boxstore.ListFiles(boxID)
+		if err != nil {
+			ctx.JSON(http.StatusNotFound, gin.H{"error": "Box not found"})
+			return
+		}
+	}
+	if hasManifest && manifest.OneTimeDownload {
+		files = stripOneTimeThumbnailState(files)
 	}
 
 	ctx.JSON(http.StatusOK, gin.H{"box_id": boxID, "expires_at": formatBrowserTime(manifest.ExpiresAt), "files": files})
@@ -216,12 +228,6 @@ func (app *App) handleOneTimeDownloadBox(ctx *gin.Context, boxID string) {
 		return
 	}
 
-	manifest.Consumed = true
-	if err := boxstore.WriteManifest(boxID, manifest); err != nil {
-		ctx.String(http.StatusInternalServerError, "Could not mark box as consumed")
-		return
-	}
-
 	files, err := boxstore.ListFiles(boxID)
 	if err != nil {
 		ctx.String(http.StatusNotFound, "Box not found")
@@ -231,41 +237,90 @@ func (app *App) handleOneTimeDownloadBox(ctx *gin.Context, boxID string) {
 		ctx.String(http.StatusConflict, "Box is not ready yet")
 		return
 	}
+
+	if app.config.OneTimeDownloadRetryOnFailure {
+		app.handleRetryableOneTimeZip(ctx, boxID, manifest, files)
+		return
+	}
+
+	manifest.Consumed = true
+	if err := boxstore.WriteManifest(boxID, manifest); err != nil {
+		ctx.String(http.StatusInternalServerError, "Could not mark box as consumed")
+		return
+	}
 	if !app.writeBoxZip(ctx, boxID, files) {
+		boxstore.DeleteBox(boxID)
 		return
 	}
 	boxstore.DeleteBox(boxID)
 }
 
 func (app *App) writeBoxZip(ctx *gin.Context, boxID string, files []models.BoxFile) bool {
+	writeBoxZipHeaders(ctx, boxID)
+	if err := writeBoxZipTo(ctx.Writer, boxID, files); err != nil {
+		ctx.Status(http.StatusInternalServerError)
+		return false
+	}
+	return true
+}
+
+func (app *App) handleRetryableOneTimeZip(ctx *gin.Context, boxID string, manifest models.BoxManifest, files []models.BoxFile) {
+	tempZip, err := os.CreateTemp("", "warpbox-"+boxID+"-*.zip")
+	if err != nil {
+		ctx.String(http.StatusInternalServerError, "Could not prepare ZIP download")
+		return
+	}
+	tempPath := tempZip.Name()
+	defer os.Remove(tempPath)
+
+	if err := writeBoxZipTo(tempZip, boxID, files); err != nil {
+		tempZip.Close()
+		ctx.String(http.StatusInternalServerError, "Could not build ZIP download")
+		return
+	}
+	if _, err := tempZip.Seek(0, 0); err != nil {
+		tempZip.Close()
+		ctx.String(http.StatusInternalServerError, "Could not read ZIP download")
+		return
+	}
+
+	writeBoxZipHeaders(ctx, boxID)
+	if _, err := io.Copy(ctx.Writer, tempZip); err != nil {
+		tempZip.Close()
+		return
+	}
+	if err := tempZip.Close(); err != nil {
+		return
+	}
+
+	manifest.Consumed = true
+	if err := boxstore.WriteManifest(boxID, manifest); err != nil {
+		return
+	}
+	boxstore.DeleteBox(boxID)
+}
+
+func writeBoxZipHeaders(ctx *gin.Context, boxID string) {
 	ctx.Header("Content-Type", "application/zip")
 	ctx.Header("Content-Disposition", fmt.Sprintf(`attachment; filename="warpbox-%s.zip"`, boxID))
+}
 
-	zipWriter := zip.NewWriter(ctx.Writer)
-	zipClosed := false
-	defer func() {
-		if !zipClosed {
-			zipWriter.Close()
-		}
-	}()
+func writeBoxZipTo(destination io.Writer, boxID string, files []models.BoxFile) error {
+	zipWriter := zip.NewWriter(destination)
 
 	for _, file := range files {
 		if !file.IsComplete {
 			continue
 		}
 		if err := boxstore.AddFileToZip(zipWriter, boxID, file.Name); err != nil {
-			ctx.Status(http.StatusInternalServerError)
-			return false
+			return err
 		}
 	}
 
 	if err := zipWriter.Close(); err != nil {
-		zipClosed = true
-		ctx.Status(http.StatusInternalServerError)
-		return false
+		return err
 	}
-	zipClosed = true
-	return true
+	return nil
 }
 
 func oneTimeDownloadLock(boxID string) *sync.Mutex {
@@ -287,6 +342,31 @@ func allFilesComplete(files []models.BoxFile) bool {
 	return true
 }
 
+func manifestFilesReady(files []models.BoxFile) bool {
+	if len(files) == 0 {
+		return false
+	}
+	for _, file := range files {
+		if file.Status != models.FileStatusReady {
+			return false
+		}
+	}
+	return true
+}
+
+func stripOneTimeThumbnailState(files []models.BoxFile) []models.BoxFile {
+	stripped := make([]models.BoxFile, 0, len(files))
+	for _, file := range files {
+		file.ThumbnailPath = nil
+		file.ThumbnailURL = ""
+		if file.ThumbnailStatus == "" {
+			file.ThumbnailStatus = models.ThumbnailStatusUnsupported
+		}
+		stripped = append(stripped, file)
+	}
+	return stripped
+}
+
 func (app *App) handleDownloadFile(ctx *gin.Context) {
 	boxID := ctx.Param("id")
 	filename, ok := helpers.SafeFilename(ctx.Param("filename"))
@@ -595,6 +675,15 @@ func (app *App) authorizeBoxRequest(ctx *gin.Context, boxID string, wantsHTML bo
 		return manifest, true, false
 	}
 
+	if manifest.OneTimeDownload && manifest.Consumed {
+		if wantsHTML {
+			ctx.String(http.StatusGone, "Box already consumed")
+		} else {
+			ctx.JSON(http.StatusGone, gin.H{"error": "Box already consumed"})
+		}
+		return manifest, true, false
+	}
+
 	if boxstore.IsPasswordProtected(manifest) && !isBoxAuthorized(ctx, boxID, manifest) {
 		if wantsHTML {
 			ctx.Redirect(http.StatusSeeOther, "/box/"+boxID+"/login")