Fix atexit handler for async drivers during shutdown (#86)

* Fix atexit handler for async drivers during shutdown

Use close=False when disposing engines in the atexit handler to avoid
MissingGreenlet errors with async drivers (e.g., aiosqlite) that require
an event loop context to close connections. The OS will clean up
connections when the process exits.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* Rename _dispose_sync to dispose_engines and make it public

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* Document dispose_engines method and engine lifecycle

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

Author: febus982

docs/manager/config.md

@@ -88,3 +88,23 @@ async with sa_manager.get_session() as session:
 
 Note that async implementation has several differences from the sync one, make sure
 to check [SQLAlchemy asyncio documentation](https://docs.sqlalchemy.org/en/20/orm/extensions/asyncio.html)
+
+## Bind engines lifecycle
+
+Engine disposal is handled automatically by `SQLAlchemyBindManager`. Engines are disposed when:
+
+* The manager instance is garbage collected
+* The Python interpreter shuts down (via an `atexit` handler)
+
+In some scenarios, such as automated tests, you may need to manually dispose engines to release database connections between tests. The `dispose_engines()` method is available for this purpose:
+
+```python
+sa_manager = SQLAlchemyBindManager(config)
+
+# ... use the manager ...
+
+# Manually dispose all engines
+sa_manager.dispose_engines()
+```
+
+This method disposes all engines synchronously, including async engines (using their underlying sync engine).

sqlalchemy_bind_manager/_bind_manager.py

@@ -91,7 +91,7 @@ def __init__(
             self.__init_bind(DEFAULT_BIND_NAME, config)
         SQLAlchemyBindManager._instances.add(self)
 
-    def _dispose_sync(self) -> None:
+    def dispose_engines(self) -> None:
         """Dispose all engines synchronously.
 
         This method is safe to call from any context, including __del__
@@ -105,7 +105,7 @@ def _dispose_sync(self) -> None:
                 bind.engine.dispose()
 
     def __del__(self) -> None:
-        self._dispose_sync()
+        self.dispose_engines()
 
     def __init_bind(self, name: str, config: SQLAlchemyConfig):
         if not isinstance(config, SQLAlchemyConfig):
@@ -232,4 +232,4 @@ def _cleanup_all_managers() -> None:
     called yet due to reference cycles or other GC timing issues.
     """
     for manager in list(SQLAlchemyBindManager._instances):
-        manager._dispose_sync()
+        manager.dispose_engines()

tests/test_sqlalchemy_bind_manager.py

@@ -115,8 +115,8 @@ def test_atexit_cleanup_disposes_all_managers(multiple_config):
 
     with patch.object(
         sa_manager,
-        "_dispose_sync",
-    ) as mocked_dispose_sync:
+        "dispose_engines",
+    ) as mocked_dispose_engines:
         _cleanup_all_managers()
 
-    mocked_dispose_sync.assert_called_once()
+    mocked_dispose_engines.assert_called_once()