feat(state): support standalone JSON state files without zip wrapper

State files can now be loaded as plain JSON files, not just zipped.
This enables simpler workflows when data is referenced via URIs.

Author: PaulHax

src/io/import/processors/restoreStateFile.ts

@@ -146,20 +146,34 @@ export async function completeStateFileRestore(
   useToolStore().deserialize(manifest, segmentGroupIDMap, stateIDToStoreID);
 }
 
-export const restoreStateFile: ImportHandler = async (dataSource) => {
-  if (dataSource.type === 'file' && (await isStateFile(dataSource.file))) {
-    const stateFileContents = await extractFilesFromZip(dataSource.file);
+async function parseManifestFromZip(file: File) {
+  const stateFileContents = await extractFilesFromZip(file);
 
-    const [manifests, restOfStateFile] = partition(
-      (dataFile) => dataFile.file.name === MANIFEST,
-      stateFileContents
-    );
+  const [manifests, restOfStateFile] = partition(
+    (dataFile) => dataFile.file.name === MANIFEST,
+    stateFileContents
+  );
 
-    if (manifests.length !== 1) {
-      throw new Error('State file does not have exactly 1 manifest');
-    }
+  if (manifests.length !== 1) {
+    throw new Error('State file does not have exactly 1 manifest');
+  }
+
+  const manifestString = await manifests[0].file.text();
+  return { manifestString, stateFiles: restOfStateFile };
+}
+
+async function parseManifestFromJson(file: File) {
+  const manifestString = await file.text();
+  return { manifestString, stateFiles: [] as FileEntry[] };
+}
+
+export const restoreStateFile: ImportHandler = async (dataSource) => {
+  if (dataSource.type === 'file' && (await isStateFile(dataSource.file))) {
+    const isJson = dataSource.fileType === 'application/json';
+    const { manifestString, stateFiles } = isJson
+      ? await parseManifestFromJson(dataSource.file)
+      : await parseManifestFromZip(dataSource.file);
 
-    const manifestString = await manifests[0].file.text();
     const migrated = migrateManifest(manifestString);
     let manifest: Manifest;
     try {
@@ -175,9 +189,9 @@ export const restoreStateFile: ImportHandler = async (dataSource) => {
 
     return {
       type: 'stateFileSetup',
-      dataSources: prepareLeafDataSources(manifest, restOfStateFile),
+      dataSources: prepareLeafDataSources(manifest, stateFiles),
       manifest,
-      stateFiles: restOfStateFile,
+      stateFiles,
     } as StateFileSetupResult;
   }
   return Skip;

src/io/state-file/index.ts

@@ -5,10 +5,11 @@ import { useLayersStore } from '@/src/store/datasets-layers';
 import { useToolStore } from '@/src/store/tools';
 import { Tools } from '@/src/store/tools/types';
 import { useViewStore } from '@/src/store/views';
-import { Manifest } from '@/src/io/state-file/schema';
+import { Manifest, ManifestSchema } from '@/src/io/state-file/schema';
 
 import { retypeFile } from '@/src/io';
 import { ARCHIVE_FILE_TYPES } from '@/src/io/mimeTypes';
+import { migrateManifest } from '@/src/io/state-file/migrations';
 import { useViewConfigStore } from '@/src/store/view-configs';
 
 export const MANIFEST = 'manifest.json';
@@ -70,11 +71,22 @@ export async function serialize() {
 
 export async function isStateFile(file: File) {
   const typedFile = await retypeFile(file);
+
   if (ARCHIVE_FILE_TYPES.has(typedFile.type)) {
     const zip = await JSZip.loadAsync(typedFile);
-
     return zip.file(MANIFEST) !== null;
   }
 
+  if (typedFile.type === 'application/json') {
+    try {
+      const text = await file.text();
+      const migrated = migrateManifest(text);
+      ManifestSchema.parse(migrated);
+      return true;
+    } catch {
+      return false;
+    }
+  }
+
   return false;
 }

tests/specs/sparse-manifest.e2e.ts

@@ -1,5 +1,10 @@
 import { MINIMAL_DICOM } from './configTestUtils';
-import { downloadFile, openVolViewPage, writeManifestToZip } from './utils';
+import {
+  downloadFile,
+  openVolViewPage,
+  writeManifestToFile,
+  writeManifestToZip,
+} from './utils';
 
 describe('Sparse manifest.json', () => {
   it('loads manifest with only URL data source', async () => {
@@ -85,4 +90,23 @@ describe('Sparse manifest.json', () => {
       }
     );
   });
+
+  it('loads standalone JSON state file (not zipped)', async () => {
+    await downloadFile(MINIMAL_DICOM.url, MINIMAL_DICOM.name);
+
+    const sparseManifest = {
+      version: '6.1.0',
+      dataSources: [
+        {
+          id: 0,
+          type: 'uri',
+          uri: `/tmp/${MINIMAL_DICOM.name}`,
+        },
+      ],
+    };
+
+    const fileName = 'standalone-state.volview.json';
+    await writeManifestToFile(sparseManifest, fileName);
+    await openVolViewPage(fileName);
+  });
 });