Spaces:
Running
Running
| """下载代理共用资源/有效价格/当前所有权核查，不把存储故障视为免费。""" | |
| from owned_thread import OwnedThreadGroup | |
| from models_sql import Ownership | |
| from purchase_transaction import effective_resource_price | |
| class ProxyAccessError(Exception): | |
| def __init__(self, status_code, message): | |
| self.status_code = status_code | |
| self.message = message | |
| super().__init__(message) | |
| def read_proxy_item(store, item_id): | |
| try: | |
| source = store.load_data('items.json', default_data=[], strict=True, skip_cache=True) | |
| if not isinstance(source, list): | |
| raise ValueError('invalid resource source') | |
| if any(not isinstance(item, dict) or not isinstance(item.get('id'), str) or not item['id'] for item in source): | |
| raise ValueError('invalid resource record') | |
| matches = [item for item in source if item.get('id') == item_id] | |
| if not matches: | |
| raise ProxyAccessError(404, '资源不存在') | |
| if len(matches) != 1: | |
| raise ValueError('ambiguous resource') | |
| item = matches[0] | |
| author = item.get('author') | |
| if not isinstance(author, str) or not author.strip(): | |
| raise ValueError('invalid resource author') | |
| effective_resource_price(item) | |
| return item | |
| except ProxyAccessError: | |
| raise | |
| except Exception: | |
| raise ProxyAccessError(503, '资源信息暂时无法核实，请稍后核对') from None | |
| def _authorized_proxy_item(store, session, item_id, account): | |
| try: | |
| item = read_proxy_item(store, item_id) | |
| author = item['author'] | |
| price = effective_resource_price(item) | |
| if price > 0 and account != author: | |
| # SQL会话仍留在调用线程；不用陈旧的身份/拥有缓存，也不授予已退款记录。 | |
| ownerships = session.query(Ownership).filter(Ownership.account == account, Ownership.item_id == item_id).populate_existing().all() | |
| if any(type(row.is_refunded) is not bool for row in ownerships): | |
| raise ValueError('invalid ownership refund state') | |
| rows = [row for row in ownerships if not row.is_refunded] | |
| if len(rows) > 1: | |
| raise ValueError('ambiguous ownership') | |
| if not rows: | |
| raise ProxyAccessError(403, '尚未获取该资源') | |
| return item | |
| except ProxyAccessError: | |
| raise | |
| except Exception: | |
| raise ProxyAccessError(503, '下载授权暂时无法核实，请稍后核对') from None | |
| finally: | |
| try: | |
| session.rollback() # 不让下载流长期持有所有权读取事务。 | |
| except Exception: | |
| raise ProxyAccessError(503, '下载授权暂时无法核实，请稍后核对') from None | |
| MAX_PROXY_ACCESS = 8 | |
| _proxy_access_io = OwnedThreadGroup(MAX_PROXY_ACCESS, | |
| lambda: ProxyAccessError(503, '下载授权暂时无法核实，请稍后核对')) | |
| start_proxy_access = _proxy_access_io.start | |
| stop_proxy_access = _proxy_access_io.stop | |
| close_proxy_access = _proxy_access_io.close | |
| async def authorized_proxy_item(store, session_factory, item_id, account): | |
| def execute(): | |
| try: | |
| with session_factory() as session: | |
| return _authorized_proxy_item(store, session, item_id, account) | |
| except ProxyAccessError: | |
| raise | |
| except Exception: | |
| raise ProxyAccessError(503, '下载授权暂时无法核实，请稍后核对') from None | |
| return await _proxy_access_io.run(execute) | |