Allow multiple same options in nova.conf

In python3 SafeConfigParser was renamed to ConfigParser and the default
for duplicate options default to true. In case of nova it is valid to
have duplicate option lines, e.g. pci_alias can be specified more then
once in nova.conf and results in an error like seen in
https://bugs.launchpad.net/tripleo/+bug/1827775

https://docs.python.org/3/library/configparser.html#configparser.ConfigParser

Closes-Bug: #1827775

Change-Id: I410af66d8dceb6dde84828c9bd1969aa623bf34c
(cherry picked from commit bbd2d94483)

container_config_scripts/nova_wait_for_compute_service.py

@@ -16,6 +16,7 @@
 import logging
 from optparse import OptionParser
 import os
+import six
 import socket
 import sys
 import time
@@ -26,7 +27,17 @@ from keystoneauth1 import session
 
 from novaclient import client
 
+# In python3 SafeConfigParser was renamed to ConfigParser and the default
+# for duplicate options default to true. In case of nova it is valid to
+# have duplicate option lines, e.g. passthrough_whitelist which leads to
+# issues reading the nova.conf
+# https://bugs.launchpad.net/tripleo/+bug/1827775
+if six.PY3:
+    from six.moves.configparser import ConfigParser
+    config = ConfigParser(strict=False)
+else:
     from six.moves.configparser import SafeConfigParser
+    config = SafeConfigParser()
 
 debug = os.getenv('__OS_DEBUG', 'false')
 
@@ -55,8 +66,10 @@ if __name__ == '__main__':
               options.insecure)
 
     if os.path.isfile(nova_cfg):
-        config = SafeConfigParser()
+        try:
             config.read(nova_cfg)
+        except Exception as e:
+            LOG.exception('Error while reading nova.conf:')
     else:
         LOG.error('Nova configuration file %s does not exist', nova_cfg)
         sys.exit(1)

container_config_scripts/nova_wait_for_placement_service.py

@@ -22,6 +22,7 @@ from __future__ import print_function
 import logging
 import os
 import re
+import six
 import sys
 import time
 
@@ -29,7 +30,18 @@ from keystoneauth1.identity import v3
 from keystoneauth1 import session
 from keystoneclient.v3 import client
 import requests
+
+# In python3 SafeConfigParser was renamed to ConfigParser and the default
+# for duplicate options default to true. In case of nova it is valid to
+# have duplicate option lines, e.g. passthrough_whitelist which leads to
+# issues reading the nova.conf
+# https://bugs.launchpad.net/tripleo/+bug/1827775
+if six.PY3:
+    from six.moves.configparser import ConfigParser
+    config = ConfigParser(strict=False)
+else:
     from six.moves.configparser import SafeConfigParser
+    config = SafeConfigParser()
 
 
 debug = os.getenv('__OS_DEBUG', 'false')
@@ -48,8 +60,10 @@ nova_cfg = '/etc/nova/nova.conf'
 
 if __name__ == '__main__':
     if os.path.isfile(nova_cfg):
-        config = SafeConfigParser()
+        try:
             config.read(nova_cfg)
+        except Exception as e:
+            LOG.exception('Error while reading nova.conf:')
     else:
         LOG.error('Nova configuration file %s does not exist', nova_cfg)
         sys.exit(1)