Added script to find unused config options.

The script analyze_opts.py is added to identify unused options
and options which are set to default values in the nova.conf file.

Change-Id: Iec42781a56f73b7d0960bdd569f5dd06edbb88df
(cherry picked from commit c5d724ff57)

tools/conf/README

@@ -1,4 +1,4 @@
-This tool is used to generate etc/nova/nova.conf.sample
+This generate_sample.sh tool is used to generate etc/nova/nova.conf.sample
 
 Run it from the top-level working directory i.e.
 
@@ -7,3 +7,14 @@ Run it from the top-level working directory i.e.
 Watch out for warnings about modules like libvirt, qpid and zmq not
 being found - these warnings are significant because they result
 in options not appearing in the generated config file.
+
+
+The analyze_opts.py tool is used to find options which appear in
+/etc/nova/nova.conf but not in etc/nova/nova.conf.sample
+This helps identify options in the nova.conf file which are not used by nova.
+The tool also identifies any options which are set to the default value.
+
+Run it from the top-level working directory i.e.
+
+  $> ./tools/conf/analyze_opts.py
+

tools/conf/analyze_opts.py

@@ -0,0 +1,80 @@
+#!/usr/bin/env python
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright (c) 2012, Cloudscaling
+# 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.
+'''
+find_unused_options.py
+
+Compare the nova.conf file with the nova.conf.sample file to find any unused
+options or default values in nova.conf
+'''
+import argparse
+import os
+import sys
+
+sys.path.append(os.getcwd())
+from nova.openstack.common import iniparser
+
+
+class PropertyCollecter(iniparser.BaseParser):
+    def __init__(self):
+        super(PropertyCollecter, self).__init__()
+        self.key_value_pairs = {}
+
+    def assignment(self, key, value):
+        self.key_value_pairs[key] = value
+
+    def new_section(self, section):
+        pass
+
+    @classmethod
+    def collect_properties(cls, lineiter, sample_format=False):
+        def clean_sample(f):
+            for line in f:
+                if line.startswith("# ") and line != '# nova.conf sample #\n':
+                    line = line[2:]
+                yield line
+        pc = cls()
+        if sample_format:
+            lineiter = clean_sample(lineiter)
+        pc.parse(lineiter)
+        return pc.key_value_pairs
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(description='''Compare the nova.conf
+    file with the nova.conf.sample file to find any unused options or
+    default values in nova.conf''')
+
+    parser.add_argument('-c', action='store',
+                        default='/etc/nova/nova.conf',
+                        help='path to nova.conf\
+                        (defaults to /etc/nova/nova.conf)')
+    parser.add_argument('-s', default='./etc/nova/nova.conf.sample',
+                        help='path to nova.conf.sample\
+                        (defaults to ./etc/nova/nova.conf.sample')
+    options = parser.parse_args()
+
+    conf_file_options = PropertyCollecter.collect_properties(open(options.c))
+    sample_conf_file_options = PropertyCollecter.collect_properties(
+        open(options.s), sample_format=True)
+
+    for k, v in sorted(conf_file_options.items()):
+        if k not in sample_conf_file_options:
+            print "Unused:", k
+    for k, v in sorted(conf_file_options.items()):
+        if k in sample_conf_file_options and v == sample_conf_file_options[k]:
+            print "Default valued:", k