Fix DBReferenceError and DBNonExistentTable with new PyMySQL version

PyMySQL 0.7.7 changed the string format of the error raised, making
oslo.db unable to catch the error:

(pymysql.err.IntegrityError) (1452, u'23000Cannot add or update a child row: a foreign key constraint fails (`vaceciqnzs`.`resource_entity`, CONSTRAINT `foo_fkey` FOREIGN KEY (`foo_id`) REFERENCES `resource_foo` (`id`))') [SQL: u'INSERT INTO resource_entity (id, foo_id) VALUES (%(id)s, %(foo_id)s)'] [parameters: {'foo_id': 2, 'id': 1}]

Change-Id: Ice7d7767842225951eaf48b71cedb2aabe5a84e4
(cherry picked from commit 1f3d509cab8c5d31f2ecd11561e1117d8c58316e)

2 files changed, 17 insertions, 40 deletions

diff --git a/oslo_db/sqlalchemy/exc_filters.py b/oslo_db/sqlalchemy/exc_filters.py
index 051d1f8..9e5a2e5 100644
--- a/oslo_db/sqlalchemy/exc_filters.py
+++ b/oslo_db/sqlalchemy/exc_filters.py
@@ -197,7 +197,7 @@ def _sqlite_dupe_key_error(integrity_error, match, engine_name, is_disconnect):
          "is (not present in|still referenced from) table "
          "\"(?P<key_table>[^\"]+)\".")
 @filters("mysql", sqla_exc.IntegrityError,
-         r".* u?'Cannot (add|delete) or update a (child|parent) row: "
+         r".*Cannot (add|delete) or update a (child|parent) row: "
          'a foreign key constraint fails \([`"].+[`"]\.[`"](?P<table>.+)[`"], '
          'CONSTRAINT [`"](?P<constraint>.+)[`"] FOREIGN KEY '
          '\([`"](?P<key>.+)[`"]\) REFERENCES [`"](?P<key_table>.+)[`"] ')
@@ -276,7 +276,7 @@ def _check_constraint_non_existing(
 @filters("sqlite", sqla_exc.OperationalError,
          r".* no such table: (?P<table>.+)")
 @filters("mysql", sqla_exc.InternalError,
-         r".*1051,.*\"Unknown table '(.+\.)?(?P<table>.+)'\"")
+         r".*1051,.*Unknown table '(.+\.)?(?P<table>.+)'\"")
 @filters("postgresql", sqla_exc.ProgrammingError,
          r".* table \"(?P<table>.+)\" does not exist")
 def _check_table_non_existing(
diff --git a/oslo_db/tests/sqlalchemy/test_exc_filters.py b/oslo_db/tests/sqlalchemy/test_exc_filters.py
index 17153a7..e31f8dd 100644
--- a/oslo_db/tests/sqlalchemy/test_exc_filters.py
+++ b/oslo_db/tests/sqlalchemy/test_exc_filters.py
@@ -512,16 +512,11 @@ class TestReferenceErrorMySQL(TestReferenceErrorSQLite,
             self.table_2.insert({'id': 1, 'foo_id': 2})
         )
 
-        self.assertInnerException(
-            matched,
-            "IntegrityError",
-            (1452, "Cannot add or update a child row: a "
-             "foreign key constraint fails (`{0}`.`resource_entity`, "
-             "CONSTRAINT `foo_fkey` FOREIGN KEY (`foo_id`) REFERENCES "
-             "`resource_foo` (`id`))".format(self.engine.url.database)),
-            "INSERT INTO resource_entity (id, foo_id) VALUES (%s, %s)",
-            (1, 2)
-        )
+        # NOTE(jd) Cannot check precisely with assertInnerException since MySQL
+        # error are not the same depending on its version…
+        self.assertIsInstance(matched.inner_exception,
+                              sqlalchemy.exc.IntegrityError)
+        self.assertEqual(matched.inner_exception.orig.args[0], 1452)
         self.assertEqual("resource_entity", matched.table)
         self.assertEqual("foo_fkey", matched.constraint)
         self.assertEqual("foo_id", matched.key)
@@ -540,19 +535,11 @@ class TestReferenceErrorMySQL(TestReferenceErrorSQLite,
                 self.table_2.insert({'id': 1, 'foo_id': 2})
             )
 
-        self.assertInnerException(
-            matched,
-            "IntegrityError",
-            (
-                1452,
-                'Cannot add or update a child row: a '
-                'foreign key constraint fails ("{0}"."resource_entity", '
-                'CONSTRAINT "foo_fkey" FOREIGN KEY ("foo_id") REFERENCES '
-                '"resource_foo" ("id"))'.format(self.engine.url.database)
-            ),
-            "INSERT INTO resource_entity (id, foo_id) VALUES (%s, %s)",
-            (1, 2)
-        )
+        # NOTE(jd) Cannot check precisely with assertInnerException since MySQL
+        # error are not the same depending on its version…
+        self.assertIsInstance(matched.inner_exception,
+                              sqlalchemy.exc.IntegrityError)
+        self.assertEqual(matched.inner_exception.orig.args[0], 1452)
         self.assertEqual("resource_entity", matched.table)
         self.assertEqual("foo_fkey", matched.constraint)
         self.assertEqual("foo_id", matched.key)
@@ -567,21 +554,11 @@ class TestReferenceErrorMySQL(TestReferenceErrorSQLite,
             self.engine.execute,
             self.table_1.delete()
         )
-        self.assertInnerException(
-            matched,
-            "IntegrityError",
-            (
-                1451,
-                "Cannot delete or update a parent row: a foreign key "
-                "constraint fails (`{0}`.`resource_entity`, "
-                "constraint `foo_fkey` "
-                "foreign key (`foo_id`) references "
-                "`resource_foo` (`id`))".format(self.engine.url.database)
-            ),
-            "DELETE FROM resource_foo",
-            (),
-        )
-
+        # NOTE(jd) Cannot check precisely with assertInnerException since MySQL
+        # error are not the same depending on its version…
+        self.assertIsInstance(matched.inner_exception,
+                              sqlalchemy.exc.IntegrityError)
+        self.assertEqual(1451, matched.inner_exception.orig.args[0])
         self.assertEqual("resource_entity", matched.table)
         self.assertEqual("foo_fkey", matched.constraint)
         self.assertEqual("foo_id", matched.key)