DRAC get_bios_config() passthru causes exception

The DRAC driver's (pxe_drac) get_bios_config() vendor passthru method
raises an AttributeError exception. It no longer returns the current
BIOS configuration. This is a regression from stable/mitaka.

Triage found that get_bios_config() mistakenly treats the value returned
by python-dracclient's list_bios_settings() as containing named tuples.
When it calls the namedtuple _asdict() method, an AttributeError
exception is raised.

Revert get_bios_config()'s handling of the return value to use __dict__.
Remove the comment that is not consistent with the implementation.

Also revert the unit test case for a successful call to use mock to
create the return value. Use mock.NonCallableMock with an empty
specification (spec) to catch this type of bug in the future.

Change-Id: I94afaa72a1ef25efc1b622e29e3a92a5d27f1892
Closes-Bug: #1637671

3 files changed, 12 insertions, 10 deletions

diff --git a/ironic/drivers/modules/drac/vendor_passthru.py b/ironic/drivers/modules/drac/vendor_passthru.py
index 07b08135e..be45ef61c 100644
--- a/ironic/drivers/modules/drac/vendor_passthru.py
+++ b/ironic/drivers/modules/drac/vendor_passthru.py
@@ -65,9 +65,7 @@ class DracVendorPassthru(base.VendorInterface):
         """
         bios_attrs = {}
         for name, bios_attr in drac_bios.get_config(task.node).items():
-            # NOTE(ifarkas): call from python-dracclient returns list of
-            #                namedtuples, converting it to dict here.
-            bios_attrs[name] = bios_attr._asdict()
+            bios_attrs[name] = bios_attr.__dict__
 
         return bios_attrs
 
diff --git a/ironic/tests/unit/drivers/modules/drac/test_bios.py b/ironic/tests/unit/drivers/modules/drac/test_bios.py
index 6561e3c35..b9933ce08 100644
--- a/ironic/tests/unit/drivers/modules/drac/test_bios.py
+++ b/ironic/tests/unit/drivers/modules/drac/test_bios.py
@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 #
-# Copyright 2015 Dell, Inc.
+# Copyright (c) 2015-2016 Dell Inc. or its subsidiaries.
 # All Rights Reserved.
 #
 #    Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -28,7 +28,6 @@ from ironic.drivers.modules.drac import common as drac_common
 from ironic.tests.unit.conductor import mgr_utils
 from ironic.tests.unit.db import base as db_base
 from ironic.tests.unit.db import utils as db_utils
-from ironic.tests.unit.drivers.modules.drac import utils as test_utils
 from ironic.tests.unit.objects import utils as obj_utils
 
 INFO_DICT = db_utils.get_test_drac_info()
@@ -51,15 +50,13 @@ class DracBIOSConfigurationTestCase(db_base.DbTestCase):
         self.addCleanup(patch_get_drac_client.stop)
 
         proc_virt_attr = {
-            'name': 'ProcVirtualization',
             'current_value': 'Enabled',
             'pending_value': None,
             'read_only': False,
             'possible_values': ['Enabled', 'Disabled']}
-        self.bios_attrs = {
-            'ProcVirtualization': test_utils.dict_to_namedtuple(
-                values=proc_virt_attr)
-        }
+        mock_proc_virt_attr = mock.NonCallableMock(spec=[], **proc_virt_attr)
+        mock_proc_virt_attr.name = 'ProcVirtualization'
+        self.bios_attrs = {'ProcVirtualization': mock_proc_virt_attr}
 
     def test_get_config(self):
         self.mock_client.list_bios_settings.return_value = self.bios_attrs
diff --git a/releasenotes/notes/drac-fix-get_bios_config-vendor-passthru-causes-exception-1e1dbeeb3e924f29.yaml b/releasenotes/notes/drac-fix-get_bios_config-vendor-passthru-causes-exception-1e1dbeeb3e924f29.yaml
new file mode 100644
index 000000000..f57b556f8
--- /dev/null
+++ b/releasenotes/notes/drac-fix-get_bios_config-vendor-passthru-causes-exception-1e1dbeeb3e924f29.yaml
@@ -0,0 +1,7 @@
+---
+fixes:
+  - Fixes an issue which caused the DRAC driver (``pxe_drac``)
+    ``get_bios_config()`` vendor passthru method to unintentionally raise an
+    ``AttributeError`` exception. That method once again returns the current
+    BIOS configuration. For more information, see
+    https://bugs.launchpad.net/ironic/+bug/1637671.