fix: wrap AsyncSession in context manager across all API blueprints

Replace all bare `session = AsyncSession(bind=conn)` assignments with
`async with AsyncSession(bind=conn) as session:` in downloads.py,
credentials.py, settings.py, sources.py, and subscriptions.py to
ensure sessions are properly closed on all code paths.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/app/api/credentials.py

@@ -19,8 +19,7 @@ VALID_PLATFORMS = ["patreon", "subscribestar", "hentaifoundry", "discord", "pixi
 async def list_credentials():
     """List all credential status (without sensitive data)."""
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             result = await session.execute(select(Credential))
             credentials = result.scalars().all()
 
@@ -48,7 +47,7 @@ async def upload_credentials():
     if extension_key:
         # Look up API key from database
         async with current_app.db_engine.connect() as conn:
-            session = AsyncSession(bind=conn)
+            async with AsyncSession(bind=conn) as session:
                 result = await session.execute(
                     select(Setting).where(Setting.key == EXTENSION_API_KEY_SETTING)
                 )
@@ -81,8 +80,7 @@ async def upload_credentials():
         return jsonify({"error": "Invalid credential type. Must be 'cookies' or 'token'"}), 400
 
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             # Check for existing credential
             result = await session.execute(
                 select(Credential).where(Credential.platform == platform)
@@ -127,8 +125,7 @@ async def delete_credentials(platform: str):
         return jsonify({"error": f"Invalid platform. Must be one of: {', '.join(VALID_PLATFORMS)}"}), 400
 
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             result = await session.execute(
                 select(Credential).where(Credential.platform == platform)
             )
@@ -160,8 +157,7 @@ async def verify_credentials():
         return jsonify({"error": f"Invalid platform. Must be one of: {', '.join(VALID_PLATFORMS)}"}), 400
 
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             result = await session.execute(
                 select(Credential).where(Credential.platform == platform)
             )

backend/app/api/downloads.py

@@ -28,8 +28,7 @@ async def list_downloads():
     per_page = min(int(request.args.get("per_page", 50)), 100)
 
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             # Build query - eager load source and subscription for labeling
             query = select(Download).options(
                 selectinload(Download.source).selectinload(Source.subscription)
@@ -89,8 +88,7 @@ async def list_downloads():
 async def get_download(download_id: int):
     """Get download details."""
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             result = await session.execute(select(Download).where(Download.id == download_id))
             download = result.scalar()
 
@@ -120,8 +118,7 @@ async def get_download(download_id: int):
 async def retry_download(download_id: int):
     """Retry a failed download."""
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             result = await session.execute(select(Download).where(Download.id == download_id))
             download = result.scalar()
 
@@ -162,8 +159,7 @@ async def recent_activity():
     cutoff = utcnow() - timedelta(days=days)
 
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             # Get failed downloads OR completed with files (noteworthy activity)
             # Exclude failed downloads that have been superseded by a later success
             # for the same source - those are stale failures the user doesn't need to see
@@ -286,8 +282,7 @@ async def get_stats():
     period = request.args.get("period", "week")  # day, week, month
 
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             # Total counts by status
             status_query = select(
                 Download.status,
@@ -356,8 +351,7 @@ async def export_failed_logs():
     cutoff_date = utcnow() - timedelta(days=days)
 
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             # Build query for failed downloads (eager load source for platform)
             query = select(Download).options(selectinload(Download.source)).where(
                 and_(

backend/app/api/settings.py

@@ -81,8 +81,7 @@ async def get_setting_value(session: AsyncSession, key: str, default=None):
 async def get_all_settings():
     """Get all application settings."""
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             result = await session.execute(select(Setting))
             settings = result.scalars().all()
 
@@ -110,8 +109,7 @@ async def update_settings():
         return jsonify({"error": "No settings provided"}), 400
 
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             for key, value in data.items():
                 # Check if setting exists
                 result = await session.execute(select(Setting).where(Setting.key == key))
@@ -142,7 +140,7 @@ async def update_settings():
 async def get_extension_api_key():
     """Get the extension API key."""
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
             api_key = await get_or_create_extension_api_key(session)
             return jsonify({"api_key": api_key})
 
@@ -151,8 +149,7 @@ async def get_extension_api_key():
 async def regenerate_extension_api_key():
     """Regenerate the extension API key."""
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             # Find existing key
             result = await session.execute(
                 select(Setting).where(Setting.key == EXTENSION_API_KEY_SETTING)
@@ -246,8 +243,7 @@ async def get_logs():
     limit = min(int(request.args.get("limit", 50)), 200)
 
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             # Get recent downloads with output logs
             query = select(Download).order_by(desc(Download.created_at)).limit(limit)
             result = await session.execute(query)
@@ -333,8 +329,7 @@ async def debug_schedule_interval():
     the worker would read.
     """
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             # Query the raw setting from database
             result = await session.execute(
                 select(Setting).where(Setting.key == "download.schedule_interval")

backend/app/api/sources.py

@@ -26,8 +26,7 @@ async def list_sources():
     per_page = min(int(request.args.get("per_page", 50)), 100)
 
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             # Build query with subscription eager loading
             query = select(Source).options(selectinload(Source.subscription))
 
@@ -83,8 +82,7 @@ async def create_source():
         return jsonify({"error": f"Invalid platform. Must be one of: {', '.join(valid_platforms)}"}), 400
 
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             # Check subscription exists
             sub_result = await session.execute(
                 select(Subscription).where(Subscription.id == data["subscription_id"])
@@ -129,8 +127,7 @@ async def create_source():
 async def get_source(source_id: int):
     """Get a single source by ID."""
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             result = await session.execute(
                 select(Source)
                 .options(selectinload(Source.subscription))
@@ -150,8 +147,7 @@ async def update_source(source_id: int):
     data = await request.get_json()
 
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             result = await session.execute(
                 select(Source)
                 .options(selectinload(Source.subscription))
@@ -182,8 +178,7 @@ async def update_source(source_id: int):
 async def delete_source(source_id: int):
     """Delete a source."""
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             result = await session.execute(
                 select(Source)
                 .options(selectinload(Source.subscription))
@@ -206,8 +201,7 @@ async def delete_source(source_id: int):
 async def trigger_check(source_id: int):
     """Trigger an immediate download check for a source."""
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             result = await session.execute(
                 select(Source)
                 .options(selectinload(Source.subscription))

backend/app/api/subscriptions.py

@@ -24,8 +24,7 @@ async def list_subscriptions():
     per_page = min(int(request.args.get("per_page", 50)), 100)
 
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             # Build query with eager loading of sources
             query = select(Subscription).options(selectinload(Subscription.sources))
 
@@ -70,8 +69,7 @@ async def create_subscription():
         return jsonify({"error": "Name is required"}), 400
 
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             # Check for duplicate name
             existing = await session.execute(
                 select(Subscription).where(Subscription.name == data["name"])
@@ -118,8 +116,7 @@ async def create_subscription():
 async def get_subscription(subscription_id: int):
     """Get a single subscription by ID with its sources."""
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             result = await session.execute(
                 select(Subscription)
                 .options(selectinload(Subscription.sources))
@@ -139,8 +136,7 @@ async def update_subscription(subscription_id: int):
     data = await request.get_json()
 
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             result = await session.execute(
                 select(Subscription)
                 .options(selectinload(Subscription.sources))
@@ -179,8 +175,7 @@ async def update_subscription(subscription_id: int):
 async def delete_subscription(subscription_id: int):
     """Delete a subscription and all its sources."""
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             result = await session.execute(
                 select(Subscription).where(Subscription.id == subscription_id)
             )
@@ -201,8 +196,7 @@ async def delete_subscription(subscription_id: int):
 async def list_subscription_sources(subscription_id: int):
     """List all sources for a subscription."""
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             result = await session.execute(
                 select(Subscription)
                 .options(selectinload(Subscription.sources))
@@ -237,8 +231,7 @@ async def add_source_to_subscription(subscription_id: int):
         return jsonify({"error": f"Invalid platform. Must be one of: {', '.join(valid_platforms)}"}), 400
 
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             # Check subscription exists
             result = await session.execute(
                 select(Subscription).where(Subscription.id == subscription_id)
@@ -290,8 +283,7 @@ async def add_source_to_subscription(subscription_id: int):
 async def trigger_subscription_check(subscription_id: int):
     """Trigger download check for all enabled sources in a subscription."""
     async with current_app.db_engine.connect() as conn:
-        session = AsyncSession(bind=conn)
+        async with AsyncSession(bind=conn) as session:
-
             result = await session.execute(
                 select(Subscription)
                 .options(selectinload(Subscription.sources))