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author | Joshua Harlow <harlowja@yahoo-inc.com> | 2012-06-07 12:42:38 -0700 |
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committer | Joshua Harlow <harlowja@yahoo-inc.com> | 2012-06-07 12:42:38 -0700 |
commit | 8900f9cba622eeaf3810003c5a6ff7522312277b (patch) | |
tree | 96dd5295a29c69eabfede0630f697325149926f3 /cloudinit/handlers/cc_update_hostname.py | |
parent | 87ebd91af8c230b8f1deed8e734297e40397eea0 (diff) | |
download | vyos-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.py | 101 |
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() |