feat(ui-components): export readAttachmentBytes for edition/overlay byte access

CHANGELOG.md

@@ -23,6 +23,18 @@
 > ship. Full per-platform walk-through:
 > [`docs/installing.md`](docs/installing.md).
 
+## Unreleased
+
+### Added
+
+- **`readAttachmentBytes(slotId)` public accessor (`@apicircle/ui-components`).**
+  A narrow, additive export that reads a stored attachment's raw bytes by its
+  `GlobalFileAsset.slotId` (or `null` when absent), so an edition / overlay can
+  resolve an asset's bytes — e.g. parse a stored OpenAPI spec for code-vs-spec
+  drift — without reaching into the internal `AttachmentRecord` shape or the
+  IndexedDB layer. Purely additive; no existing behavior changes.
+  (`@apicircle/ui-components`)
+
 ## 1.3.0 - 2026-07-18
 
 _All workspace packages move to **1.3.0** in lockstep — the published

packages/ui-components/src/index.ts

@@ -4,6 +4,7 @@ export { applyFont, ALL_FONTS } from './theme/applyFont';
 export type { FontFamilyId, FontFamilyDef } from './theme/applyFont';
 export { applyFontSize, clampFontSizePercent } from './theme/applyFontSize';
 export { useWorkspaceStore } from './store/workspaceStore';
+export { readAttachmentBytes } from './persistence/attachments';
 export { Button, Input, Modal, cn } from './primitives';
 export { PANELS, getPanel } from './layout/panels';
 export type { PanelDef } from './layout/panels';

packages/ui-components/src/persistence/attachments.test.ts

@@ -6,6 +6,7 @@ import {
   getAttachment,
   materializeAttachment,
   putAttachment,
+  readAttachmentBytes,
 } from './attachments';
 
 const sampleBytes = (str: string) => new TextEncoder().encode(str);
@@ -32,6 +33,22 @@ describe('attachments IDB store', () => {
     expect(await getAttachment('nope')).toBeNull();
   });
 
+  it('readAttachmentBytes returns the stored bytes, or null when absent', async () => {
+    await putAttachment({
+      slotId: 'slot-bytes',
+      filename: 'spec.json',
+      mimeType: 'application/json',
+      size: 5,
+      sha256: 'ab',
+      savedAt: '2026-04-27T00:00:00.000Z',
+      bytes: sampleBytes('hello'),
+    });
+    const bytes = await readAttachmentBytes('slot-bytes');
+    expect(bytes).not.toBeNull();
+    expect(new TextDecoder().decode(bytes!)).toBe('hello');
+    expect(await readAttachmentBytes('missing')).toBeNull();
+  });
+
   it('deleteAttachment removes the record', async () => {
     await putAttachment({
       slotId: 'slot-2',

packages/ui-components/src/persistence/attachments.ts

@@ -64,6 +64,19 @@ export async function getAttachment(slotId: string): Promise<AttachmentRecord |
   });
 }
 
+/**
+ * Read a stored attachment's raw bytes by its `slotId` (`GlobalFileAsset.slotId`),
+ * or `null` when the slot has no bytes on this device (e.g. an asset uploaded on
+ * another machine and not yet pulled). A narrow public accessor — re-exported from
+ * the package root — so an edition / overlay can resolve an asset's bytes (e.g.
+ * parse a stored OpenAPI spec for code-vs-spec drift) without depending on the
+ * internal `AttachmentRecord` shape or the IndexedDB layer.
+ */
+export async function readAttachmentBytes(slotId: string): Promise<Uint8Array | null> {
+  const record = await getAttachment(slotId);
+  return record ? record.bytes : null;
+}
+
 export async function deleteAttachment(slotId: string): Promise<void> {
   const db = await openDb();
   return new Promise<void>((resolve, reject) => {