Merge "Deprecate scoped_session usage with async sessions"

zzzeek · Gerrit Code Review · commit 5219a0e25ba7 · 2021-08-23T16:39:09.000Z
diff --git a/doc/build/changelog/unreleased_14/6746.rst b/doc/build/changelog/unreleased_14/6746.rst
@@ -0,0 +1,7 @@
+.. change::
+    :tags: orm
+    :tickets: 6746
+
+    Deprecate usage of :class:`_orm.scoped_session` with asyncio drivers.
+    When using Asyncio the :class:`_asyncio.async_scoped_session` should
+    be used instead.
diff --git a/lib/sqlalchemy/ext/asyncio/scoping.py b/lib/sqlalchemy/ext/asyncio/scoping.py
@@ -63,6 +63,8 @@ class async_scoped_session(ScopedSessionMixin):
 
     """
 
+    _support_async = True
+
     def __init__(self, session_factory, scopefunc):
         """Construct a new :class:`_asyncio.async_scoped_session`.
 
diff --git a/lib/sqlalchemy/ext/asyncio/session.py b/lib/sqlalchemy/ext/asyncio/session.py
@@ -53,6 +53,8 @@ class AsyncSession(ReversibleProxy):
 
     """
 
+    _is_asyncio = True
+
     __slots__ = (
         "binds",
         "bind",
diff --git a/lib/sqlalchemy/orm/scoping.py b/lib/sqlalchemy/orm/scoping.py
@@ -13,6 +13,7 @@
 from ..util import ScopedRegistry
 from ..util import ThreadLocalRegistry
 from ..util import warn
+from ..util import warn_deprecated
 
 __all__ = ["scoped_session", "ScopedSessionMixin"]
 
@@ -42,9 +43,16 @@ def __call__(self, **kw):
             else:
                 sess = self.session_factory(**kw)
                 self.registry.set(sess)
-                return sess
         else:
-            return self.registry()
+            sess = self.registry()
+        if not self._support_async and sess._is_asyncio:
+            warn_deprecated(
+                "Using `scoped_session` with asyncio is deprecated and "
+                "will raise an error in a future version. "
+                "Please use `async_scoped_session` instead.",
+                "1.4.23",
+            )
+        return sess
 
     def configure(self, **kwargs):
         """reconfigure the :class:`.sessionmaker` used by this
@@ -116,8 +124,16 @@ class scoped_session(ScopedSessionMixin):
 
     See :ref:`unitofwork_contextual` for a tutorial.
 
+    ..warning::
+
+       When using :ref:`asyncio_toplevel` the async
+       version :class:`_asyncio.async_scoped_session` should be
+       used instead.
+
     """
 
+    _support_async = False
+
     session_factory = None
     """The `session_factory` provided to `__init__` is stored in this
     attribute and may be accessed at a later time.  This can be useful when
diff --git a/lib/sqlalchemy/orm/session.py b/lib/sqlalchemy/orm/session.py
@@ -948,6 +948,8 @@ class Session(_SessionClassMethods):
 
     """
 
+    _is_asyncio = False
+
     @util.deprecated_params(
         autocommit=(
             "2.0",
diff --git a/test/orm/test_deprecations.py b/test/orm/test_deprecations.py
@@ -38,7 +38,9 @@
 from sqlalchemy.orm import mapper
 from sqlalchemy.orm import relation
 from sqlalchemy.orm import relationship
+from sqlalchemy.orm import scoped_session
 from sqlalchemy.orm import Session
+from sqlalchemy.orm import sessionmaker
 from sqlalchemy.orm import subqueryload
 from sqlalchemy.orm import synonym
 from sqlalchemy.orm import undefer
@@ -54,6 +56,7 @@
 from sqlalchemy.testing import AssertsCompiledSQL
 from sqlalchemy.testing import eq_
 from sqlalchemy.testing import eq_ignore_whitespace
+from sqlalchemy.testing import expect_deprecated
 from sqlalchemy.testing import fixtures
 from sqlalchemy.testing import is_
 from sqlalchemy.testing import is_true
@@ -5475,3 +5478,23 @@ def test_bind_base_table_concrete_sub_class(self):
         session = self._fixture({self.tables.base_table: base_class_bind})
 
         is_(session.get_bind(self.classes.ConcreteSubClass), testing.db)
+
+
+class DeprecationScopedSessionTest(fixtures.MappedTest):
+    def test_config_errors(self):
+        sm = sessionmaker()
+
+        def go():
+            s = sm()
+            s._is_asyncio = True
+            return s
+
+        Session = scoped_session(go)
+
+        with expect_deprecated(
+            "Using `scoped_session` with asyncio is deprecated and "
+            "will raise an error in a future version. "
+            "Please use `async_scoped_session` instead."
+        ):
+            Session()
+        Session.remove()
