fix: Race conditions when adding many library items (#10013)

* Fix for race condition when adding many library items

* Remove unused import

* Replace any with LibraryItem type

* Fix comments on pr

* Fix build errors

* Fix hoisted variable

* new mime type

* duplicate before passing down to be sure

* lint

* fix tests

* Remove unused import

---------

Co-authored-by: dwelle <5153846+dwelle@users.noreply.github.com>

packages/common/src/constants.ts

@@ -266,7 +266,10 @@ export const STRING_MIME_TYPES = {
   json: "application/json",
   // excalidraw data
   excalidraw: "application/vnd.excalidraw+json",
+  // LEGACY: fully-qualified library JSON data
   excalidrawlib: "application/vnd.excalidrawlib+json",
+  // list of excalidraw library item ids
+  excalidrawlibIds: "application/vnd.excalidrawlib.ids+json",
 } as const;
 
 export const MIME_TYPES = {

packages/excalidraw/components/App.tsx

@@ -433,6 +433,8 @@ import { findShapeByKey } from "./shapes";
 
 import UnlockPopup from "./UnlockPopup";
 
+import type { ExcalidrawLibraryIds } from "../data/types";
+
 import type {
   RenderInteractiveSceneCallback,
   ScrollBars,
@@ -10545,16 +10547,44 @@ class App extends React.Component<AppProps, AppState> {
     if (imageFiles.length > 0 && this.isToolSupported("image")) {
       return this.insertImages(imageFiles, sceneX, sceneY);
     }
-
-    const libraryJSON = dataTransferList.getData(MIME_TYPES.excalidrawlib);
-    if (libraryJSON && typeof libraryJSON === "string") {
+    const excalidrawLibrary_ids = dataTransferList.getData(
+      MIME_TYPES.excalidrawlibIds,
+    );
+    const excalidrawLibrary_data = dataTransferList.getData(
+      MIME_TYPES.excalidrawlib,
+    );
+    if (excalidrawLibrary_ids || excalidrawLibrary_data) {
       try {
-        const libraryItems = parseLibraryJSON(libraryJSON);
-        this.addElementsFromPasteOrLibrary({
-          elements: distributeLibraryItemsOnSquareGrid(libraryItems),
-          position: event,
-          files: null,
-        });
+        let libraryItems: LibraryItems | null = null;
+        if (excalidrawLibrary_ids) {
+          const { itemIds } = JSON.parse(
+            excalidrawLibrary_ids,
+          ) as ExcalidrawLibraryIds;
+          const allLibraryItems = await this.library.getLatestLibrary();
+          libraryItems = allLibraryItems.filter((item) =>
+            itemIds.includes(item.id),
+          );
+          // legacy library dataTransfer format
+        } else if (excalidrawLibrary_data) {
+          libraryItems = parseLibraryJSON(excalidrawLibrary_data);
+        }
+        if (libraryItems?.length) {
+          libraryItems = libraryItems.map((item) => ({
+            ...item,
+            // #6465
+            elements: duplicateElements({
+              type: "everything",
+              elements: item.elements,
+              randomizeSeed: true,
+            }).duplicatedElements,
+          }));
+
+          this.addElementsFromPasteOrLibrary({
+            elements: distributeLibraryItemsOnSquareGrid(libraryItems),
+            position: event,
+            files: null,
+          });
+        }
       } catch (error: any) {
         this.setState({ errorMessage: error.message });
       }

packages/excalidraw/components/LibraryMenuItems.tsx

@@ -10,7 +10,6 @@ import { MIME_TYPES, arrayToMap } from "@excalidraw/common";
 
 import { duplicateElements } from "@excalidraw/element";
 
-import { serializeLibraryAsJSON } from "../data/json";
 import { useLibraryCache } from "../hooks/useLibraryItemSvg";
 import { useScrollPosition } from "../hooks/useScrollPosition";
 import { t } from "../i18n";
@@ -27,6 +26,8 @@ import Stack from "./Stack";
 
 import "./LibraryMenuItems.scss";
 
+import type { ExcalidrawLibraryIds } from "../data/types";
+
 import type {
   ExcalidrawProps,
   LibraryItem,
@@ -175,12 +176,17 @@ export default function LibraryMenuItems({
 
   const onItemDrag = useCallback(
     (id: LibraryItem["id"], event: React.DragEvent) => {
+      // we want to serialize just the ids so the operation is fast and there's
+      // no race condition if people drop the library items on canvas too fast
+      const data: ExcalidrawLibraryIds = {
+        itemIds: selectedItems.includes(id) ? selectedItems : [id],
+      };
       event.dataTransfer.setData(
-        MIME_TYPES.excalidrawlib,
-        serializeLibraryAsJSON(getInsertedElements(id)),
+        MIME_TYPES.excalidrawlibIds,
+        JSON.stringify(data),
       );
     },
-    [getInsertedElements],
+    [selectedItems],
   );
 
   const isItemSelected = useCallback(

packages/excalidraw/data/library.ts

@@ -192,6 +192,7 @@ const createLibraryUpdate = (
 class Library {
   /** latest libraryItems */
   private currLibraryItems: LibraryItems = [];
+
   /** snapshot of library items since last onLibraryChange call */
   private prevLibraryItems = cloneLibraryItems(this.currLibraryItems);
 

packages/excalidraw/data/types.ts

@@ -6,6 +6,7 @@ import type { cleanAppStateForExport } from "../appState";
 import type {
   AppState,
   BinaryFiles,
+  LibraryItem,
   LibraryItems,
   LibraryItems_anyVersion,
 } from "../types";
@@ -59,3 +60,7 @@ export interface ImportedLibraryData extends Partial<ExportedLibraryData> {
   /** @deprecated v1 */
   library?: LibraryItems;
 }
+
+export type ExcalidrawLibraryIds = {
+  itemIds: LibraryItem["id"][];
+};

packages/excalidraw/tests/library.test.tsx

@@ -15,7 +15,7 @@ import { Excalidraw } from "../index";
 
 import { API } from "./helpers/api";
 import { UI } from "./helpers/ui";
-import { fireEvent, getCloneByOrigId, render, waitFor } from "./test-utils";
+import { fireEvent, render, waitFor } from "./test-utils";
 
 import type { LibraryItem, LibraryItems } from "../types";
 
@@ -46,52 +46,8 @@ vi.mock("../data/filesystem.ts", async (importOriginal) => {
   };
 });
 
-describe("library", () => {
+describe("library items inserting", () => {
   beforeEach(async () => {
-    await render(<Excalidraw />);
-    await act(() => {
-      return h.app.library.resetLibrary();
-    });
-  });
-
-  it("import library via drag&drop", async () => {
-    expect(await h.app.library.getLatestLibrary()).toEqual([]);
-    await API.drop([
-      {
-        kind: "file",
-        type: MIME_TYPES.excalidrawlib,
-        file: await API.loadFile("./fixtures/fixture_library.excalidrawlib"),
-      },
-    ]);
-    await waitFor(async () => {
-      expect(await h.app.library.getLatestLibrary()).toEqual([
-        {
-          status: "unpublished",
-          elements: [expect.objectContaining({ id: "A" })],
-          id: "id0",
-          created: expect.any(Number),
-        },
-      ]);
-    });
-  });
-
-  // NOTE: mocked to test logic, not actual drag&drop via UI
-  it("drop library item onto canvas", async () => {
-    expect(h.elements).toEqual([]);
-    const libraryItems = parseLibraryJSON(await libraryJSONPromise);
-    await API.drop([
-      {
-        kind: "string",
-        value: serializeLibraryAsJSON(libraryItems),
-        type: MIME_TYPES.excalidrawlib,
-      },
-    ]);
-    await waitFor(() => {
-      expect(h.elements).toEqual([expect.objectContaining({ [ORIG_ID]: "A" })]);
-    });
-  });
-
-  it("should regenerate ids but retain bindings on library insert", async () => {
     const rectangle = API.createElement({
       id: "rectangle1",
       type: "rectangle",
@@ -117,45 +73,116 @@ describe("library", () => {
       },
     });
 
+    const libraryItems: LibraryItems = [
+      {
+        id: "libraryItem_id0",
+        status: "unpublished",
+        elements: [rectangle, text, arrow],
+        created: 0,
+        name: "test",
+      },
+    ];
+
+    await render(<Excalidraw initialData={{ libraryItems }} />);
+  });
+
+  afterEach(async () => {
+    await act(() => {
+      return h.app.library.resetLibrary();
+    });
+  });
+
+  it("should regenerate ids but retain bindings on library insert", async () => {
+    const libraryItems = await h.app.library.getLatestLibrary();
+
+    expect(libraryItems.length).toBe(1);
+
     await API.drop([
       {
         kind: "string",
-        value: serializeLibraryAsJSON([
-          {
-            id: "item1",
-            status: "published",
-            elements: [rectangle, text, arrow],
-            created: 1,
-          },
-        ]),
-        type: MIME_TYPES.excalidrawlib,
+        value: JSON.stringify({
+          itemIds: [libraryItems[0].id],
+        }),
+        type: MIME_TYPES.excalidrawlibIds,
       },
     ]);
 
     await waitFor(() => {
+      const rectangle = h.elements.find((e) => e.type === "rectangle")!;
+      const text = h.elements.find((e) => e.type === "text")!;
+      const arrow = h.elements.find((e) => e.type === "arrow")!;
       expect(h.elements).toEqual(
         expect.arrayContaining([
           expect.objectContaining({
-            [ORIG_ID]: "rectangle1",
+            type: "rectangle",
+            id: expect.not.stringMatching("rectangle1"),
             boundElements: expect.arrayContaining([
-              { type: "text", id: getCloneByOrigId("text1").id },
-              { type: "arrow", id: getCloneByOrigId("arrow1").id },
+              { type: "text", id: text.id },
+              { type: "arrow", id: arrow.id },
             ]),
           }),
           expect.objectContaining({
-            [ORIG_ID]: "text1",
-            containerId: getCloneByOrigId("rectangle1").id,
+            type: "text",
+            id: expect.not.stringMatching("text1"),
+            containerId: rectangle.id,
           }),
           expect.objectContaining({
-            [ORIG_ID]: "arrow1",
+            type: "arrow",
+            id: expect.not.stringMatching("arrow1"),
             endBinding: expect.objectContaining({
-              elementId: getCloneByOrigId("rectangle1").id,
+              elementId: rectangle.id,
             }),
           }),
         ]),
       );
     });
   });
+});
+
+describe("library", () => {
+  beforeEach(async () => {
+    await render(<Excalidraw />);
+    await act(() => {
+      return h.app.library.resetLibrary();
+    });
+  });
+
+  it("import library via drag&drop", async () => {
+    expect(await h.app.library.getLatestLibrary()).toEqual([]);
+    await API.drop([
+      {
+        kind: "file",
+        type: MIME_TYPES.excalidrawlib,
+        file: await API.loadFile("./fixtures/fixture_library.excalidrawlib"),
+      },
+    ]);
+    await waitFor(async () => {
+      expect(await h.app.library.getLatestLibrary()).toEqual([
+        {
+          status: "unpublished",
+          elements: [expect.objectContaining({ id: "A" })],
+          id: expect.any(String),
+          created: expect.any(Number),
+        },
+      ]);
+    });
+  });
+
+  // NOTE: mocked to test logic, not actual drag&drop via UI
+  it("drop library item onto canvas", async () => {
+    expect(h.elements).toEqual([]);
+    const libraryItems = parseLibraryJSON(await libraryJSONPromise);
+    await API.drop([
+      {
+        kind: "string",
+        value: serializeLibraryAsJSON(libraryItems),
+        type: MIME_TYPES.excalidrawlib,
+      },
+    ]);
+    await waitFor(() => {
+      expect(h.elements).toEqual([expect.objectContaining({ [ORIG_ID]: "A" })]);
+    });
+  });
 
   it("should fix duplicate ids between items on insert", async () => {
     // note, we're not testing for duplicate group ids and such because