feat: Implement cancellation of stale generations in the service and repository, along with a new test.

tests/test_scheduler.py

@@ -0,0 +1,52 @@
+import asyncio
+import os
+from datetime import datetime, timedelta, UTC
+from motor.motor_asyncio import AsyncIOMotorClient
+from models.Generation import Generation, GenerationStatus
+from repos.generation_repo import GenerationRepo
+from dotenv import load_dotenv
+
+load_dotenv()
+
+# Mock configs if not present in env
+MONGO_HOST = os.getenv("MONGO_HOST", "mongodb://localhost:27017")
+DB_NAME = os.getenv("DB_NAME", "bot_db")
+
+print(f"Connecting to MongoDB: {MONGO_HOST}, DB: {DB_NAME}")
+
+async def test_scheduler():
+    client = AsyncIOMotorClient(MONGO_HOST)
+    repo = GenerationRepo(client, db_name=DB_NAME)
+    
+    # 1. Create a "stale" generation (2 hours ago)
+    stale_gen = Generation(
+        prompt="stale test",
+        status=GenerationStatus.RUNNING,
+        created_at=datetime.now(UTC) - timedelta(minutes=120),
+        assets_list=[],
+        aspect_ratio="NINESIXTEEN",
+        quality="ONEK"
+    )
+    gen_id = await repo.create_generation(stale_gen)
+    print(f"Created stale generation: {gen_id}")
+    
+    # 2. Run cleanup
+    print("Running cleanup...")
+    count = await repo.cancel_stale_generations(timeout_minutes=60)
+    print(f"Cleaned up {count} generations")
+    
+    # 3. Verify status
+    updated_gen = await repo.get_generation(gen_id)
+    print(f"Generation status: {updated_gen.status}")
+    print(f"Failed reason: {updated_gen.failed_reason}")
+    
+    if updated_gen.status == GenerationStatus.FAILED:
+        print("✅ SUCCESS: Generation marked as FAILED")
+    else:
+        print("❌ FAILURE: Generation status not updated")
+
+    # Cleanup
+    await repo.collection.delete_one({"_id": updated_gen.id}) # Remove test data
+
+if __name__ == "__main__":
+    asyncio.run(test_scheduler())