From 0366529cc9f018fdcce4b2f56e884f332278ef35 Mon Sep 17 00:00:00 2001
From: Sean Dague <sean@dague.net>
Date: Tue, 17 Jan 2017 09:03:50 -0500
Subject: [PATCH] initial take at merging local.conf code

---
 devstack/cmd.py    | 22 +++++++++++++++++++---
 devstack/dsconf.py | 24 ++++++++++++++++++++++++
 2 files changed, 43 insertions(+), 3 deletions(-)

diff --git a/devstack/cmd.py b/devstack/cmd.py
index da8a502..5e54219 100644
--- a/devstack/cmd.py
+++ b/devstack/cmd.py
@@ -50,6 +50,11 @@ def setlc_conf(local_conf, args):
     local_conf.set(args.group, args.conf, args.section, args.name, args.value)
 
 
+def merge(local_conf, args):
+    for source in args.sources:
+        local_conf.merge_lc(source)
+
+
 def parse_args(argv):
     parser = argparse.ArgumentParser(prog='dsconf')
     subparsers = parser.add_subparsers(title='commands',
@@ -120,14 +125,25 @@ def parse_args(argv):
     parser_setlc_conf.add_argument('name')
     parser_setlc_conf.add_argument('value')
 
-    return parser.parse_args()
+    parser_merge = subparsers.add_parser(
+        'merge_lc', help='merge local.conf files')
+    parser_merge.set_defaults(func=merge)
+    parser_merge.add_argument('local_conf')
+    parser_merge.add_argument('sources', nargs='+')
+
+    return parser.parse_args(), parser
 
 
 def main(argv=None):
-    args = parse_args(argv or sys.argv)
+    args, parser = parse_args(argv or sys.argv)
     if hasattr(args, 'inifile'):
         f = devstack.dsconf.IniFile(args.inifile)
     elif hasattr(args, 'local_conf'):
         f = devstack.dsconf.LocalConf(args.local_conf)
-    args.func(f, args)
+
+    if hasattr(args, 'func'):
+        args.func(f, args)
+    else:
+        parser.print_help()
+        return 1
     return
diff --git a/devstack/dsconf.py b/devstack/dsconf.py
index 9e9ff6c..66071cd 100644
--- a/devstack/dsconf.py
+++ b/devstack/dsconf.py
@@ -145,6 +145,17 @@ class LocalConf(object):
                 if m2:
                     yield current_section, m2.group(1), m2.group(2)
 
+    def groups(self):
+        """Return a list of all groups in the local.conf"""
+        groups = []
+        with open(self.fname) as reader:
+            for line in reader.readlines():
+                m = re.match(r"\[\[([^\[\]]+)\|([^\[\]]+)\]\]", line)
+                if m:
+                    group = (m.group(1), m.group(2))
+                    groups.append(group)
+        return groups
+
     def _section(self, group, conf):
         """Yield all the lines out of a meta section."""
         in_section = False
@@ -283,3 +294,16 @@ class LocalConf(object):
         def _do_set(writer, line):
             writer.write("%s = %s\n" % (name, value))
         self._at_insert_point(group, conf, section, name, _do_set)
+
+    def merge_lc(self, lcfile):
+        lc = LocalConf(lcfile)
+        groups = lc.groups()
+        for group, conf in groups:
+            if group == "local":
+                for line in lc._section(group, conf):
+                    m = re.match(r"(\w+)\s*\=\s*(.+)", line)
+                    if m:
+                        self.set_local(m.group(1), m.group(2))
+            else:
+                for section, name, value in lc._conf(group, conf):
+                    lc.set(group, conf, section, name, value)