1b074576fe
原先 OSError、ValueError、ValidationError 统一归并为「不可用 或字段不正确」，文件不存在和字段写错无法区分，排障困难。 拆分为两条消息分别指示故障类别，仍不回显文件内容与路径。 Co-Authored-By: Claude Code <noreply@anthropic.com>
116 lines
4.3 KiB
Python
116 lines
4.3 KiB
Python
"""T+ 只读 SQL Server 连接。
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T+ 是外部源库，业务接口不直接依赖它。连接采用延迟初始化，未配置或未启用
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时不会影响主业务服务启动；适配器执行查询时才建立连接池。
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"""
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import json
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from collections.abc import Generator
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from pathlib import Path
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from pydantic import BaseModel, ConfigDict, Field, SecretStr, ValidationError
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from sqlalchemy import Engine, create_engine, event
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from sqlalchemy.orm import Session, sessionmaker
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from app.core.config import Settings, get_settings
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_engine: Engine | None = None
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_session_factory: sessionmaker[Session] | None = None
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class _ConnectionFile(BaseModel):
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"""连接文件仅允许源库字段，密码不会出现在模型表示中。"""
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model_config = ConfigDict(extra="forbid", strict=True)
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host: str = Field(min_length=1, max_length=255)
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port: int = Field(ge=1, le=65535)
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database: str = Field(min_length=1, max_length=128)
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user: str = Field(min_length=1, max_length=128)
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password: SecretStr
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driver: str = Field(min_length=1, max_length=128)
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def resolve_tplus_settings(settings: Settings) -> Settings:
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"""解析显式配置的只读连接，返回副本，不修改应用全局配置。"""
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if not settings.t_plus_enabled:
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raise RuntimeError("T+ 数据源未启用，请设置 T_PLUS_ENABLED=true")
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resolved = settings
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if settings.t_plus_connection_file:
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try:
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path = Path(settings.t_plus_connection_file)
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if path.stat().st_size > 16384:
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raise ValueError("连接文件过大")
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config = _ConnectionFile.model_validate(
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json.loads(path.read_text(encoding="utf-8-sig"))
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)
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except OSError:
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# 消息只区分故障类别，不回显路径内容；路径本身可在应用配置中核对。
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raise RuntimeError("T+ 只读连接文件不存在或不可读") from None
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except (ValueError, ValidationError):
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raise RuntimeError("T+ 只读连接文件字段不正确") from None
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values = {
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"t_plus_" + key: getattr(config, key) for key in ("host", "port", "database", "user")
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}
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values.update(
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t_plus_password=config.password.get_secret_value(), t_plus_odbc_driver=config.driver
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)
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resolved = settings.model_copy(update=values)
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if resolved.t_plus_user.strip().casefold() == "sa":
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raise RuntimeError("应用必须使用 T+ 专用只读账号，不能使用 sa")
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if not resolved.t_plus_database or not resolved.t_plus_user or not resolved.t_plus_odbc_driver:
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raise RuntimeError("T+ 只读连接缺少数据库、账号或已验证的 ODBC 驱动")
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return resolved
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def get_tplus_engine() -> Engine:
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"""获取 T+ 只读引擎；未启用或缺少 ODBC 驱动时给出可读错误。"""
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global _engine, _session_factory
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if _engine is not None:
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return _engine
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settings = resolve_tplus_settings(get_settings())
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try:
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_engine = create_engine(
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settings.t_plus_database_url,
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pool_pre_ping=True,
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pool_recycle=1800,
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pool_timeout=settings.t_plus_connect_timeout,
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echo=False,
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hide_parameters=True,
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)
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except ModuleNotFoundError as exc:
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raise RuntimeError(
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"T+ 连接需要 pyodbc（uv sync --extra tplus）和已验证的 SQL Server ODBC 驱动"
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) from exc
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_session_factory = sessionmaker(_engine, expire_on_commit=False)
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def configure_timeout(connection, _record):
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connection.timeout = settings.t_plus_query_timeout
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event.listen(_engine, "connect", configure_timeout)
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return _engine
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def get_tplus_session_factory() -> sessionmaker[Session]:
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"""获取 T+ SQLAlchemy 会话工厂。"""
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get_tplus_engine()
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assert _session_factory is not None
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return _session_factory
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def get_tplus_db() -> Generator[Session, None, None]:
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"""提供只读 T+ 会话；调用方不得 commit 或执行写操作。"""
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factory = get_tplus_session_factory()
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with factory() as session:
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yield session
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def dispose_tplus_engine() -> None:
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"""释放 T+ 连接池。"""
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global _engine, _session_factory
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if _engine is not None:
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_engine.dispose()
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_engine = None
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_session_factory = None
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