Files
Nexus/server/infrastructure/database/platform_node_repo.py
T
Your Name 99201f48fd fix: MissingGreenlet error — convert all middleware to pure ASGI
Root cause: BaseHTTPMiddleware.call_next() runs the endpoint in a
separate async task, which breaks SQLAlchemy's greenlet context.
After session.commit(), the connection is released to the pool.
When session.refresh() tries to acquire a new connection for a
SELECT, it fails with MissingGreenlet because the greenlet spawn
context is not available in the call_next() task.

Fix (two-part):
1. Convert all 4 middleware classes from BaseHTTPMiddleware to pure
   ASGI middleware — eliminates call_next() entirely so the entire
   request chain runs in the same async context.
2. Set expire_on_commit=False on the session factory — after commit,
   objects retain their in-memory values instead of being expired.
   This removes the need for session.refresh() entirely.

All session.refresh() calls removed from 11 repository files.
With expire_on_commit=False, post-commit attribute access no longer
triggers lazy loads that would also fail with MissingGreenlet.

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>
2026-05-25 15:24:15 +08:00

83 lines
2.8 KiB
Python

"""Nexus — Platform & Node Repository (Async SQLAlchemy)"""
from typing import Optional, List
from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession
from server.domain.models import Platform, Node
class PlatformRepositoryImpl:
def __init__(self, session: AsyncSession):
self.session = session
async def get_by_id(self, id: int) -> Optional[Platform]:
result = await self.session.execute(select(Platform).where(Platform.id == id))
return result.scalar_one_or_none()
async def get_all(self) -> List[Platform]:
result = await self.session.execute(select(Platform).order_by(Platform.id))
return list(result.scalars().all())
async def get_by_type(self, platform_type: str) -> Optional[Platform]:
result = await self.session.execute(select(Platform).where(Platform.type == platform_type))
return result.scalar_one_or_none()
async def create(self, platform: Platform) -> Platform:
self.session.add(platform)
await self.session.commit()
return platform
async def update(self, platform: Platform) -> Platform:
await self.session.commit()
return platform
async def delete(self, id: int) -> bool:
platform = await self.get_by_id(id)
if platform:
await self.session.delete(platform)
await self.session.commit()
return True
return False
class NodeRepositoryImpl:
def __init__(self, session: AsyncSession):
self.session = session
async def get_by_id(self, id: int) -> Optional[Node]:
result = await self.session.execute(select(Node).where(Node.id == id))
return result.scalar_one_or_none()
async def get_all(self) -> List[Node]:
result = await self.session.execute(select(Node).order_by(Node.sort_order, Node.id))
return list(result.scalars().all())
async def get_children(self, parent_id: int) -> List[Node]:
result = await self.session.execute(
select(Node).where(Node.parent_id == parent_id).order_by(Node.sort_order, Node.id)
)
return list(result.scalars().all())
async def get_root_nodes(self) -> List[Node]:
result = await self.session.execute(
select(Node).where(Node.parent_id.is_(None)).order_by(Node.sort_order, Node.id)
)
return list(result.scalars().all())
async def create(self, node: Node) -> Node:
self.session.add(node)
await self.session.commit()
return node
async def update(self, node: Node) -> Node:
await self.session.commit()
return node
async def delete(self, id: int) -> bool:
node = await self.get_by_id(id)
if node:
await self.session.delete(node)
await self.session.commit()
return True
return False