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,