Merge "DB locks shouldn't squelch errors"

swift/common/db.py

@@ -581,16 +581,15 @@ class DatabaseBroker(object):
         conn.execute('BEGIN IMMEDIATE')
         try:
             yield True
-        except (Exception, Timeout):
-            pass
-        try:
-            conn.execute('ROLLBACK')
-            conn.isolation_level = orig_isolation_level
-            self.conn = conn
-        except (Exception, Timeout):
-            logging.exception(
-                _('Broker error trying to rollback locked connection'))
-            conn.close()
+        finally:
+            try:
+                conn.execute('ROLLBACK')
+                conn.isolation_level = orig_isolation_level
+                self.conn = conn
+            except (Exception, Timeout):
+                logging.exception(
+                    _('Broker error trying to rollback locked connection'))
+                conn.close()
 
     def _new_db_id(self):
         device_name = os.path.basename(self.get_device_path())

test/unit/common/test_db.py

@@ -914,13 +914,27 @@ class TestDatabaseBroker(unittest.TestCase):
             pass
         with broker.lock():
             pass
+
+        with self.assertRaises(RuntimeError) as raised, broker.lock():
+            raise RuntimeError('boom!')
+        self.assertEqual(raised.exception.args[0], 'boom!')
+
         broker2 = DatabaseBroker(os.path.join(self.testdir, '1.db'),
                                  timeout=.1)
         broker2._initialize = stub
         with broker.lock():
-            with self.assertRaises(LockTimeout) as raised, \
-                    broker2.lock():
-                pass
+            # broker2 raises the timeout
+            with self.assertRaises(LockTimeout) as raised:
+                with broker2.lock():
+                    pass
+        self.assertEqual(str(raised.exception),
+                         '0.1 seconds: %s' % broker.db_file)
+
+        # and the timeout bubbles up out of broker.lock()
+        with self.assertRaises(LockTimeout) as raised:
+            with broker.lock():
+                with broker2.lock():
+                    pass
         self.assertEqual(str(raised.exception),
                          '0.1 seconds: %s' % broker.db_file)