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authorJoshua Harlow <harlowja@yahoo-inc.com>2012-06-07 12:42:38 -0700
committerJoshua Harlow <harlowja@yahoo-inc.com>2012-06-07 12:42:38 -0700
commit8900f9cba622eeaf3810003c5a6ff7522312277b (patch)
tree96dd5295a29c69eabfede0630f697325149926f3 /cloudinit/handlers/cc_update_hostname.py
parent87ebd91af8c230b8f1deed8e734297e40397eea0 (diff)
downloadvyos-cloud-init-8900f9cba622eeaf3810003c5a6ff7522312277b.tar.gz
vyos-cloud-init-8900f9cba622eeaf3810003c5a6ff7522312277b.zip
1. Adding some new helper files that split off file inclusion, templating, importing, constant usage.
1. Move all datasources to a new sources directory 1. Rename some files to be more consistent with python file/module naming.
Diffstat (limited to 'cloudinit/handlers/cc_update_hostname.py')
-rw-r--r--cloudinit/handlers/cc_update_hostname.py101
1 files changed, 101 insertions, 0 deletions
diff --git a/cloudinit/handlers/cc_update_hostname.py b/cloudinit/handlers/cc_update_hostname.py
new file mode 100644
index 00000000..b9d1919a
--- /dev/null
+++ b/cloudinit/handlers/cc_update_hostname.py
@@ -0,0 +1,101 @@
+# vi: ts=4 expandtab
+#
+# Copyright (C) 2011 Canonical Ltd.
+# Copyright (C) 2012 Hewlett-Packard Development Company, L.P.
+#
+# Author: Scott Moser <scott.moser@canonical.com>
+# Author: Juerg Haefliger <juerg.haefliger@hp.com>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 3, as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+import cloudinit.util as util
+import subprocess
+import errno
+from cloudinit.CloudConfig import per_always
+
+frequency = per_always
+
+
+def handle(_name, cfg, cloud, log, _args):
+ if util.get_cfg_option_bool(cfg, "preserve_hostname", False):
+ log.debug("preserve_hostname is set. not updating hostname")
+ return
+
+ (hostname, _fqdn) = util.get_hostname_fqdn(cfg, cloud)
+ try:
+ prev = "%s/%s" % (cloud.get_cpath('data'), "previous-hostname")
+ update_hostname(hostname, prev, log)
+ except Exception:
+ log.warn("failed to set hostname\n")
+ raise
+
+
+# read hostname from a 'hostname' file
+# allow for comments and stripping line endings.
+# if file doesn't exist, or no contents, return default
+def read_hostname(filename, default=None):
+ try:
+ fp = open(filename, "r")
+ lines = fp.readlines()
+ fp.close()
+ for line in lines:
+ hpos = line.find("#")
+ if hpos != -1:
+ line = line[0:hpos]
+ line = line.rstrip()
+ if line:
+ return line
+ except IOError as e:
+ if e.errno != errno.ENOENT:
+ raise
+ return default
+
+
+def update_hostname(hostname, prev_file, log):
+ etc_file = "/etc/hostname"
+
+ hostname_prev = None
+ hostname_in_etc = None
+
+ try:
+ hostname_prev = read_hostname(prev_file)
+ except Exception as e:
+ log.warn("Failed to open %s: %s" % (prev_file, e))
+
+ try:
+ hostname_in_etc = read_hostname(etc_file)
+ except:
+ log.warn("Failed to open %s" % etc_file)
+
+ update_files = []
+ if not hostname_prev or hostname_prev != hostname:
+ update_files.append(prev_file)
+
+ if (not hostname_in_etc or
+ (hostname_in_etc == hostname_prev and hostname_in_etc != hostname)):
+ update_files.append(etc_file)
+
+ try:
+ for fname in update_files:
+ util.write_file(fname, "%s\n" % hostname, 0644)
+ log.debug("wrote %s to %s" % (hostname, fname))
+ except:
+ log.warn("failed to write hostname to %s" % fname)
+
+ if hostname_in_etc and hostname_prev and hostname_in_etc != hostname_prev:
+ log.debug("%s differs from %s. assuming user maintained" %
+ (prev_file, etc_file))
+
+ if etc_file in update_files:
+ log.debug("setting hostname to %s" % hostname)
+ subprocess.Popen(['hostname', hostname]).communicate()