fix(session-export): preserve streamed browser downloads

packages/session-query/session-export/tests/client-apply.client.spec.tsx

@@ -43,12 +43,10 @@ describe('session-export browser plugin', () => {
     expect(entry?.component).toBe(SessionExportHeader)
     expect(entry?.options).toMatchObject({ id: 'session-export' })
     const injected = (entry?.inject as unknown as () => import('../src/client/Dialog.tsx').SessionExportDialogInjected)()
-    b.ctx.sessionExport.fail(SID, 'failed')
+    await injected.request(SID)
     expect(b.ctx.sessionExport.store.getSnapshot().bySession[SID]?.status).toBe('error')
     injected.dismiss(SID)
     expect(b.ctx.sessionExport.store.getSnapshot().bySession[SID]?.open).toBe(false)
-    await injected.request(SID)
-    expect(b.ctx.sessionExport.store.getSnapshot().bySession[SID]?.status).toBe('error')
 
     await b.fiber.dispose()
     expect(b.slots.entries('conversation.session.header.utilities')).toHaveLength(0)

packages/session-query/session-export/tests/controller.client.spec.ts

@@ -2,7 +2,7 @@
 import { afterEach, describe, expect, it, vi } from 'vitest'
 import type { SessionId } from '@deepseek-ai/dsh-client-runtime/client'
 import {
-  downloadBlob, SessionExportDownloadController, sessionLogZipFilename,
+  downloadUrl, SessionExportDownloadController, sessionLogZipFilename,
 } from '../src/client/controller.ts'
 
 const SID = 'session-export-controller' as SessionId
@@ -25,9 +25,12 @@ describe('SessionExportDownloadController', () => {
     expect(url.pathname).toBe('/api/session.export')
     expect(url.searchParams.get('sessionId')).toBe(SID)
     expect(url.searchParams.get('includeDescendants')).toBe('true')
+    expect(init.method).toBe('HEAD')
     expect(init.signal).toBeInstanceOf(AbortSignal)
-    expect(save).toHaveBeenCalledWith(expect.any(Object), 'dsh-session-session-export-controller.zip')
-    expect((save.mock.calls[0]?.[0] as Blob).size).toBe(3)
+    expect(save).toHaveBeenCalledWith(
+      url.toString(),
+      'dsh-session-session-export-controller.zip',
+    )
     expect(controller.store.getSnapshot().bySession[SID]).toEqual({
       open: true, status: 'success', error: null,
     })
@@ -50,7 +53,7 @@ describe('SessionExportDownloadController', () => {
     controller.dismiss(SID)
   })
 
-  it('publishes HTTP, transport, and command failures without leaking rejections', async () => {
+  it('publishes HTTP and transport failures without leaking rejections', async () => {
     const http = new SessionExportDownloadController(
       async () => new Response('backend unavailable', { status: 500 }), vi.fn(),
     )
@@ -65,8 +68,6 @@ describe('SessionExportDownloadController', () => {
     await transport.download(SID)
     expect(transport.store.getSnapshot().bySession[SID]?.error).toBe('offline')
 
-    transport.fail(SID, 'command failed')
-    expect(transport.store.getSnapshot().bySession[SID]?.error).toBe('command failed')
     transport.dismiss('absent' as SessionId)
 
     const emptyDetail = new SessionExportDownloadController(
@@ -102,14 +103,14 @@ describe('SessionExportDownloadController', () => {
     vi.stubGlobal('location', { origin: 'null' })
     const fetcher = vi.fn(async (_input: string | URL, _init?: RequestInit) => new Response('zip'))
     vi.stubGlobal('fetch', fetcher)
-    vi.spyOn(URL, 'createObjectURL').mockReturnValue('blob:default')
-    vi.spyOn(URL, 'revokeObjectURL').mockImplementation(() => {})
-    vi.spyOn(HTMLAnchorElement.prototype, 'click').mockImplementation(() => {})
+    const click = vi.spyOn(HTMLAnchorElement.prototype, 'click').mockImplementation(() => {})
     const controller = new SessionExportDownloadController()
 
     await controller.download(SID)
 
     expect((fetcher.mock.calls[0]?.[0] as URL).origin).toBe('http://dsh.internal')
+    expect(fetcher.mock.calls[0]?.[1]).toMatchObject({ method: 'HEAD' })
+    expect(click).toHaveBeenCalledOnce()
   })
 
   it('defaults dialog openness when state is externally cleared before settlement', async () => {
@@ -132,19 +133,14 @@ describe('SessionExportDownloadController', () => {
 })
 
 describe('browser download helpers', () => {
-  it('sanitizes the archive filename and revokes the object URL after the click', () => {
-    vi.useFakeTimers()
-    const create = vi.spyOn(URL, 'createObjectURL').mockReturnValue('blob:session')
-    const revoke = vi.spyOn(URL, 'revokeObjectURL').mockImplementation(() => {})
+  it('sanitizes the archive filename and hands the URL to a download anchor', () => {
     const click = vi.spyOn(HTMLAnchorElement.prototype, 'click').mockImplementation(() => {})
 
     expect(sessionLogZipFilename('a/b' as SessionId)).toBe('dsh-session-a_b.zip')
-    downloadBlob(new Blob(['zip']), 'archive.zip')
-    expect(create).toHaveBeenCalledOnce()
+    downloadUrl('http://host/api/session.export?sessionId=a', 'archive.zip')
     expect(click).toHaveBeenCalledOnce()
-    expect(revoke).not.toHaveBeenCalled()
-    vi.runAllTimers()
-    expect(revoke).toHaveBeenCalledWith('blob:session')
-    vi.useRealTimers()
+    const anchor = click.mock.instances[0] as HTMLAnchorElement
+    expect(anchor.href).toBe('http://host/api/session.export?sessionId=a')
+    expect(anchor.download).toBe('archive.zip')
   })
 })

packages/session-query/session-export/tests/dialog.client.spec.tsx

@@ -33,7 +33,11 @@ afterEach(cleanup)
 describe('SessionExportDialog', () => {
   it('shows a controller failure and closes it without reading Session history', async () => {
     const b = bench()
-    act(() => { b.controller.fail(SID, 'toolbar failed') })
+    act(() => {
+      b.controller.store.set({
+        bySession: { [SID]: { open: true, status: 'error', error: 'toolbar failed' } },
+      })
+    })
     const dialog = await b.view.findByRole('dialog', { name: 'Session export failed' })
     expect(dialog.textContent).toContain('toolbar failed')
     const close = b.view.getAllByRole('button', { name: 'Close' })[0]
@@ -57,7 +61,11 @@ describe('SessionExportDialog', () => {
 
   it('uses fallback copy when a failure has no detail', async () => {
     const b = bench()
-    act(() => { b.controller.fail(SID, '') })
+    act(() => {
+      b.controller.store.set({
+        bySession: { [SID]: { open: true, status: 'error', error: '' } },
+      })
+    })
     const dialog = await b.view.findByRole('dialog', { name: 'Session export failed' })
     expect(dialog.textContent).toContain('Could not start the Session export.')
     const close = b.view.getAllByRole('button', { name: 'Close' }).at(-1)

packages/session-query/session-export/tests/loader-composition.client.spec.ts

@@ -54,7 +54,8 @@ describe('session-export real Loader composition', () => {
     })
     await context.loader.await()
 
-    const session = context.sessions.create(SessionId('loader-session-export'), { meta: { createdAt: 1 } })
+    const session = (context.get('sessions') as unknown as SessionStore)
+      .create(SessionId('loader-session-export'), { meta: { createdAt: 1 } })
     const agent = { session, status: 'idle', options: {} } as unknown as Agent
     expect(context.commands.list(agent)).toContainEqual({
       name: 'export', description: 'Download this Session log as a ZIP archive',