Fix the --help flag for printing help on twistd-based services

nova/flags.py

@@ -90,6 +90,12 @@ class FlagValues(gflags.FlagValues):
         self.ClearDirty()
         return args
 
+    def Reset(self):
+        gflags.FlagValues.Reset(self)
+        self.__dict__['__dirty'] = []
+        self.__dict__['__was_already_parsed'] = False
+        self.__dict__['__stored_argv'] = []
+
     def SetDirty(self, name):
         """Mark a flag as dirty so that accessing it will case a reparse."""
         self.__dict__['__dirty'].append(name)

nova/tests/flags_unittest.py

@@ -20,6 +20,8 @@ from nova import exception
 from nova import flags
 from nova import test
 
+FLAGS = flags.FLAGS
+flags.DEFINE_string('flags_unittest', 'foo', 'for testing purposes only')
 
 class FlagsTestCase(test.TrialTestCase):
     def setUp(self):
@@ -85,3 +87,13 @@ class FlagsTestCase(test.TrialTestCase):
 
         self.assert_('runtime_answer' in self.global_FLAGS)
         self.assertEqual(self.global_FLAGS.runtime_answer, 60)
+
+    def test_flag_leak_left(self):
+        self.assertEqual(FLAGS.flags_unittest, 'foo')
+        FLAGS.flags_unittest = 'bar'
+        self.assertEqual(FLAGS.flags_unittest, 'bar')
+
+    def test_flag_leak_right(self):
+        self.assertEqual(FLAGS.flags_unittest, 'foo')
+        FLAGS.flags_unittest = 'bar'
+        self.assertEqual(FLAGS.flags_unittest, 'bar')

nova/tests/twistd_unittest.py

@@ -0,0 +1,53 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright 2010 United States Government as represented by the
+# Administrator of the National Aeronautics and Space Administration.
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+import StringIO
+import sys
+
+from nova import twistd
+from nova import exception
+from nova import flags
+from nova import test
+
+
+FLAGS = flags.FLAGS
+
+
+class TwistdTestCase(test.TrialTestCase):
+    def setUp(self):
+        super(TwistdTestCase, self).setUp()
+        self.Options = twistd.WrapTwistedOptions(twistd.TwistdServerOptions)
+        sys.stdout = StringIO.StringIO()
+
+    def tearDown(self):
+        super(TwistdTestCase, self).tearDown()
+        sys.stdout = sys.__stdout__
+
+    def test_basic(self):
+        options = self.Options()
+        argv = options.parseOptions()
+
+    def test_logfile(self):
+        options = self.Options()
+        argv = options.parseOptions(['--logfile=foo'])
+        self.assertEqual(FLAGS.logfile, 'foo')
+
+    def test_help(self):
+        options = self.Options()
+        self.assertRaises(SystemExit, options.parseOptions, ['--help'])
+        self.assert_('pidfile' in sys.stdout.getvalue())

nova/twistd.py

@@ -51,6 +51,8 @@ class TwistdServerOptions(ServerOptions):
 
 
 class FlagParser(object):
+    # this is a required attribute for gflags
+    syntactic_help = ''
     def __init__(self, parser):
         self.parser = parser
 
@@ -81,6 +83,8 @@ def WrapTwistedOptions(wrapped):
             reflect.accumulateClassList(self.__class__, 'optFlags', twistd_flags)
             for flag in twistd_flags:
                 key = flag[0].replace('-', '_')
+                if hasattr(FLAGS, key):
+                    continue
                 flags.DEFINE_boolean(key, None, str(flag[-1]))
 
         def _absorbParameters(self):
@@ -88,6 +92,8 @@ def WrapTwistedOptions(wrapped):
             reflect.accumulateClassList(self.__class__, 'optParameters', twistd_params)
             for param in twistd_params:
                 key = param[0].replace('-', '_')
+                if hasattr(FLAGS, key):
+                    continue
                 if len(param) > 4:
                     flags.DEFINE(FlagParser(param[4]),
                                  key, param[2], str(param[3]),

run_tests.py

@@ -61,6 +61,7 @@ from nova.tests.quota_unittest import *
 from nova.tests.rpc_unittest import *
 from nova.tests.scheduler_unittest import *
 from nova.tests.service_unittest import *
+from nova.tests.twistd_unittest import *
 from nova.tests.validator_unittest import *
 from nova.tests.virt_unittest import *
 from nova.tests.volume_unittest import *