feat(export): add metadata file to preserve page icons and ordering on import (#1877)

* feat(export): add metadata file to preserve page icons and ordering on import
- Export includes `docmost-metadata.json`
- Import reads metadata to restore icons and sort siblings by original position

* cleanup

* bonus fixes

* handle unknown prosemirror nodes

* add docmost app  version

apps/server/src/integrations/export/export.service.ts

@@ -20,11 +20,17 @@ import {
   replaceInternalLinks,
   updateAttachmentUrlsToLocalPaths,
 } from './utils';
+import {
+  ExportMetadata,
+  ExportPageMetadata,
+} from '../../common/helpers/types/export-metadata.types';
 import { PageRepo } from '@docmost/db/repos/page/page.repo';
 import { Node } from '@tiptap/pm/model';
 import { EditorState } from '@tiptap/pm/state';
 // eslint-disable-next-line @typescript-eslint/no-require-imports
 import slugify = require('@sindresorhus/slugify');
+// eslint-disable-next-line @typescript-eslint/no-require-imports
+const packageJson = require('../../../package.json');
 import { EnvironmentService } from '../environment/environment.service';
 import {
   getAttachmentIds,
@@ -155,12 +161,15 @@ export class ExportService {
         'pages.id',
         'pages.slugId',
         'pages.title',
+        'pages.icon',
+        'pages.position',
         'pages.content',
         'pages.parentPageId',
         'pages.spaceId',
         'pages.workspaceId',
       ])
       .where('spaceId', '=', spaceId)
+      .where('deletedAt', 'is', null)
       .execute();
 
     const tree = buildTree(pages as Page[]);
@@ -189,10 +198,12 @@ export class ExportService {
     includeAttachments: boolean,
   ): Promise<void> {
     const slugIdToPath: Record<string, string> = {};
+    const pageIdToFilePath: Record<string, string> = {};
+    const pagesMetadata: Record<string, ExportPageMetadata> = {};
 
     computeLocalPath(tree, format, null, '', slugIdToPath);
 
-    const stack: { folder: JSZip; parentPageId: string }[] = [
+    const stack: { folder: JSZip; parentPageId: string | null }[] = [
       { folder: zip, parentPageId: null },
     ];
 
@@ -232,12 +243,33 @@ export class ExportService {
           `${pageTitle}${getExportExtension(format)}`,
           pageExportContent,
         );
+
+        pageIdToFilePath[page.id] = currentPagePath;
+
+        const parentPath = parentPageId ? pageIdToFilePath[parentPageId] : null;
+        pagesMetadata[currentPagePath] = {
+          pageId: page.id,
+          slugId: page.slugId,
+          icon: page.icon ?? null,
+          position: page.position,
+          parentPath,
+        };
+
         if (childPages.length > 0) {
           const pageFolder = folder.folder(pageTitle);
           stack.push({ folder: pageFolder, parentPageId: page.id });
         }
       }
     }
+
+    const metadata: ExportMetadata = {
+      exportedAt: new Date().toISOString(),
+      source: 'docmost',
+      version: packageJson.version,
+      pages: pagesMetadata,
+    };
+
+    zip.file('docmost-metadata.json', JSON.stringify(metadata, null, 2));
   }
 
   async zipAttachments(prosemirrorJson: any, spaceId: string, zip: JSZip) {