System config niceness!

1. Move out the old helpers that provided oop access/reading/writing
   to various standard conf files and place those in parsers instead.
2. Unify the 'update_hostname' which varied very little	between	distros
   and make it generic so that subclasses can only provide a couple of 
   functions to	obtain the hostname updating functionality
3. Implement that new set of functions in rhel/debian    
4. Use the new parsers chop_comment function for similar use 
   cases as well as add a new utils make header	function that
   can be used for configuration files that are	newly generated
   to use (less	duplication here of this same thing being done
   in multiple places.
5. Add in a distro '_apply_hostname' which calls out to	the 'hostname'
   program to set the system hostname (more duplication	elimination).
6. Make the 'constant' filenames being written to for configuration
   by the various distros be instance members instead of string
   constants 'sprinkled' throughout the code

1 files changed, 10 insertions, 5 deletions

diff --git a/cloudinit/util.py b/cloudinit/util.py
index 79676305..918deba2 100644
--- a/cloudinit/util.py
+++ b/cloudinit/util.py
@@ -52,6 +52,7 @@ from cloudinit import importer
 from cloudinit import log as logging
 from cloudinit import safeyaml
 from cloudinit import url_helper as uhelp
+from cloudinit import version
 
 from cloudinit.settings import (CFG_BUILTIN)
 
@@ -272,11 +273,7 @@ def uniq_merge(*lists):
             # Kickout the empty ones
             a_list = [a for a in a_list if len(a)]
         combined_list.extend(a_list)
-    uniq_list = []
-    for i in combined_list:
-        if i not in uniq_list:
-            uniq_list.append(i)
-    return uniq_list
+    return uniq_list(combined_list)
 
 
 def clean_filename(fn):
@@ -1429,6 +1426,14 @@ def subp(args, data=None, rcs=None, env=None, capture=True, shell=False,
     return (out, err)
 
 
+def make_header(comment_char="#", base='created'):
+    ci_ver = version.version_string()
+    header = str(comment_char)
+    header += " %s by cloud-init v. %s" % (base.title(), ci_ver)
+    header += " on %s" % time_rfc2822()
+    return header
+
+
 def abs_join(*paths):
     return os.path.abspath(os.path.join(*paths))