LKE-13676 fix: limit thumbnail size

Author: William Gorge

src/api/Visualization/types.ts

@@ -148,7 +148,15 @@ export interface IVisualizationTimeline {
 }
 
 export interface VisualizationThumbnailData {
-  svg: string;
+  svg: string; // Should not exceed a certain size, cf isThumbnailTooLarge
+}
+
+export const MAX_VISUALIZATION_THUMBNAIL_SIZE_BYTES = 2_097_152; // 2MB
+
+export function isThumbnailTooLarge(thumbnail: VisualizationThumbnailData | undefined): boolean {
+  const thumbnailContent = thumbnail?.svg ?? '';
+  const thumbnailSizeBytes = new TextEncoder().encode(thumbnailContent).byteLength;
+  return thumbnailSizeBytes > MAX_VISUALIZATION_THUMBNAIL_SIZE_BYTES;
 }
 
 export interface BaseVisualization {