- Fixed an issue in baked queries where the .get() method, used either

directly or within lazy loads, didn't consider the mapper's "get clause"
as part of the cache key, causing bound parameter mismatches if the
clause got re-generated.  This clause is cached by mappers
on the fly but in highly concurrent scenarios may be generated more
than once when first accessed.
fixes #3597

diff --git a/doc/build/changelog/changelog_10.rst b/doc/build/changelog/changelog_10.rst
index 7e289a526be0a866a027803cb3bf7b7b08d8e8ac..8d6dcd2a99ac09a858f34dc917339cb3dbed106d 100644 (file)
--- a/doc/build/changelog/changelog_10.rst
+++ b/doc/build/changelog/changelog_10.rst
@@ -18,6 +18,18 @@
 .. changelog::
     :version: 1.0.10
 
+    .. change::
+        :tags: bug, ext
+        :versions: 1.1.0b1
+        :tickets: 3597
+
+        Fixed an issue in baked queries where the .get() method, used either
+        directly or within lazy loads, didn't consider the mapper's "get clause"
+        as part of the cache key, causing bound parameter mismatches if the
+        clause got re-generated.  This clause is cached by mappers
+        on the fly but in highly concurrent scenarios may be generated more
+        than once when first accessed.
+
     .. change::
         :tags: feature, sql
         :versions: 1.1.0b1

diff --git a/lib/sqlalchemy/ext/baked.py b/lib/sqlalchemy/ext/baked.py
index ee9f6f9bbc7d222f7aa45d509522918d1628d07e..eb0c36805eb5aee615fc0fb0275ef550170aa2c5 100644 (file)
--- a/lib/sqlalchemy/ext/baked.py
+++ b/lib/sqlalchemy/ext/baked.py
@@ -354,6 +354,12 @@ class Result(object):
         # (remember, we can map to an OUTER JOIN)
         bq = self.bq
 
+        # add the clause we got from mapper._get_clause to the cache
+        # key so that if a race causes multiple calls to _get_clause,
+        # we've cached on ours
+        bq = bq._clone()
+        bq._cache_key += (_get_clause, )
+
         bq = bq.with_criteria(setup, tuple(elem is None for elem in ident))
 
         params = dict([

diff --git a/test/ext/test_baked.py b/test/ext/test_baked.py
index dcf333184c9c6d053a1d392051af658eb9b9957c..7004358fcfa83cd2a8089dc48116b73bd6007f4b 100644 (file)
--- a/test/ext/test_baked.py
+++ b/test/ext/test_baked.py
@@ -271,6 +271,30 @@ class LikeQueryTest(BakedTest):
             eq_(u2.name, 'chuck')
         self.assert_sql_count(testing.db, go, 0)
 
+    def test_get_includes_getclause(self):
+        # test issue #3597
+        User = self.classes.User
+
+        bq = self.bakery(lambda s: s.query(User))
+
+        for i in range(5):
+            sess = Session()
+            u1 = bq(sess).get(7)
+            eq_(u1.name, 'jack')
+
+        eq_(len(bq._bakery), 2)
+
+        # simulate race where mapper._get_clause
+        # may be generated more than once
+        from sqlalchemy import inspect
+        del inspect(User).__dict__['_get_clause']
+
+        for i in range(5):
+            sess = Session()
+            u1 = bq(sess).get(7)
+            eq_(u1.name, 'jack')
+        eq_(len(bq._bakery), 4)
+
 
 class ResultTest(BakedTest):
     __backend__ = True