feat: queue voice session cover generation jobs

backend/tests/test_generation_jobs.py

@@ -8,7 +8,7 @@ from httpx import ASGITransport, AsyncClient
 from sqlalchemy import select
 
 from app.db.database import get_db
-from app.db.models import GenerationJob, GenerationJobEvent
+from app.db.models import GenerationJob, GenerationJobEvent, Story
 from app.main import app
 from app.services.adapters import AdapterConfig
 from app.services.adapters.storybook.primary import Storybook, StorybookPage
@@ -20,7 +20,7 @@ from app.services.generation_jobs import (
     mark_stale_generation_jobs,
     record_generation_event,
 )
-from app.services.story_service import run_generation_job_service
+from app.services.story_service import queue_story_asset_generation, run_generation_job_service
 
 pytestmark = pytest.mark.asyncio
 
@@ -225,6 +225,86 @@ async def test_asset_retry_records_job_events_and_updates_retryable_assets(
         app.dependency_overrides.clear()
 
 
+async def test_queue_story_asset_generation_dispatches_background_job(
+    db_session,
+    test_story,
+):
+    task_delay_path = "app.tasks.generation_workflow.run_generation_workflow_task.delay"
+
+    with patch(task_delay_path) as mock_delay:
+        summary = await queue_story_asset_generation(
+            test_story.id,
+            test_story.user_id,
+            ["image"],
+            db_session,
+        )
+
+    assert summary["output_mode"] == "asset_generation"
+    assert summary["input_type"] == "image"
+    assert summary["status"] == "running"
+    assert summary["current_step"] == "request_accepted"
+    mock_delay.assert_called_once_with(summary["id"])
+
+    job = (
+        await db_session.execute(
+            select(GenerationJob).where(GenerationJob.id == summary["id"])
+        )
+    ).scalar_one()
+    assert job.story_id == test_story.id
+    assert job.output_mode == "asset_generation"
+
+
+async def test_asset_generation_job_worker_completes_cover_image(
+    db_session,
+    test_story,
+):
+    job = await create_generation_job(
+        db_session,
+        user_id=test_story.user_id,
+        output_mode="asset_generation",
+        input_type="image",
+        request_payload={"story_id": test_story.id, "assets": ["image"]},
+        story_id=test_story.id,
+    )
+
+    with patch(
+        "app.services.story_service.generate_image",
+        new_callable=AsyncMock,
+    ) as mock_generate_image:
+        mock_generate_image.return_value = "https://example.com/async-cover.png"
+
+        await run_generation_job_service(job.id, db_session)
+
+    refreshed_job = (
+        await db_session.execute(select(GenerationJob).where(GenerationJob.id == job.id))
+    ).scalar_one()
+    assert refreshed_job.status == "completed"
+    assert refreshed_job.current_step == "asset_generation_completed"
+    assert refreshed_job.result_snapshot["image_status"] == "ready"
+
+    story = (
+        await db_session.execute(
+            select(Story).where(Story.id == test_story.id)
+        )
+    ).scalar_one()
+    assert story.image_url == "https://example.com/async-cover.png"
+
+    events = (
+        await db_session.execute(
+            select(GenerationJobEvent)
+            .where(GenerationJobEvent.job_id == job.id)
+            .order_by(GenerationJobEvent.id)
+        )
+    ).scalars().all()
+    assert [event.event_type for event in events] == [
+        "request_accepted",
+        "worker_started",
+        "cover_image_started",
+        "cover_image_succeeded",
+        "asset_generation_completed",
+    ]
+
+
 async def test_storybook_generation_is_queued_then_worker_records_page_image_events(
     db_session,
     auth_token,

backend/tests/test_voice_sessions.py

@@ -99,9 +99,9 @@ async def test_voice_session_correct_turn_and_finalize_to_story(
             new_callable=AsyncMock,
         ) as mock_tts,
         patch(
-            "app.services.voice_session_service.generate_story_cover",
+            "app.services.voice_session_service.queue_story_asset_generation",
             new_callable=AsyncMock,
-        ) as mock_generate_cover,
+        ) as mock_queue_asset_generation,
     ):
         mock_generate.side_effect = [
             StoryOutput(
@@ -118,7 +118,23 @@ async def test_voice_session_correct_turn_and_finalize_to_story(
             ),
         ]
         mock_tts.side_effect = [b"turn-1-audio", b"turn-2-audio"]
-        mock_generate_cover.return_value = "https://example.com/voice-cover.png"
+        mock_queue_asset_generation.return_value = {
+            "id": "cover-job-123",
+            "story_id": 1,
+            "output_mode": "asset_generation",
+            "input_type": "image",
+            "status": "running",
+            "current_step": "request_accepted",
+            "progress_percent": 5,
+            "progress_label": "已接收请求",
+            "is_terminal": False,
+            "can_cancel": True,
+            "can_retry": False,
+            "result_snapshot": {},
+            "error_message": None,
+            "created_at": "2026-04-20T00:00:00Z",
+            "updated_at": "2026-04-20T00:00:00Z",
+        }
 
         transport = ASGITransport(app=app)
         try:
@@ -156,6 +172,7 @@ async def test_voice_session_correct_turn_and_finalize_to_story(
                 finalize_data = response.json()
                 story_id = finalize_data["story_id"]
                 assert finalize_data["status"] == "completed"
+                assert finalize_data["generation_job_id"] == "cover-job-123"
 
                 response = await client.get(f"/api/stories/{story_id}")
                 assert response.status_code == 200
@@ -172,7 +189,7 @@ async def test_voice_session_correct_turn_and_finalize_to_story(
                 assert session_data["final_story_id"] == story_id
                 assert session_data["can_continue"] is False
                 assert session_data["story_state"]["final_summary"]
-                mock_generate_cover.assert_awaited_once()
+                mock_queue_asset_generation.assert_awaited_once()
         finally:
             app.dependency_overrides.clear()