ansible/system/host
2013-09-19 20:09:38 +02:00

211 lines
6.7 KiB
Python

#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# (c) 2013, René Moser <mail@renemoser.net>
#
# This file is part of Ansible
#
# Ansible is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Ansible 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 Ansible. If not, see <http://www.gnu.org/licenses/>.
DOCUMENTATION = '''
---
module: host
author: René Moser
version_added: "1.4"
short_description: Add or remove entries in /etc/hosts
requirements:
description:
- Manage entries in /etc/hosts
options:
ip:
required: false
description:
- IP address. Required on state "present".
hostname:
required: false
description:
- name of host. Required on state "present".
aliases:
required: false
description:
- list of alias hostnames, comma separated.
state:
required: false
default: "present"
choices: [ present, absent ]
description:
- Whether the entries should be present or not in /etc/hosts.
'''
EXAMPLES = '''
# Example host command from Ansible Playbooks
- host: ip=127.0.0.1 hostname=localhost aliases=foobar.com,localhost.foobar.com
- host: ip=127.0.0.1 hostname=localhost state=present
- host: ip=192.168.1.1 state=absent
- host: hostname=localhost state=absent
- host: ip=::1 hostname=localhost aliases=ip6-localhost,ip6-loopback
'''
import os
import tempfile
import fileinput
import syslog
class Host(object):
HOSTSFILE = '/etc/hosts'
def __init__(self, module):
self.module = module
self.state = module.params['state']
self.ip = module.params['ip']
self.hostname = module.params['hostname']
self.aliases = module.params['aliases']
self.changed = False
self.ip_matches = False
self.hostname_matches = False
self.aliases_matches = False
self.has_aliases = False
self.found_on_line = -1
self.syslogging = False
def validate_has_hostname_on_present(self):
err = ''
if self.state == 'present' and not (self.hostname and self.ip):
err = "Error: No param 'hostnames' or 'ip' given in state 'present'."
return err
def validate_has_ip_or_hostname_on_absent(self):
err = ''
if self.state == 'absent':
if not (self.hostname or self.ip):
err = "Error: Either param 'hostnames' or 'ip' must be given in state 'absent'."
if self.hostname and self.ip:
err = "Error: Either param 'hostnames' or 'ip' must be given in state 'absent'."
return err
def log(self, msg):
if self.syslogging:
syslog.openlog('ansible-%s' % os.path.basename(__file__))
syslog.syslog(syslog.LOG_NOTICE, '' + msg)
def proceed_hosts_entries(self):
f = open(self.HOSTSFILE,'rb')
self.lines = f.readlines()
f.close()
for lineno, line in enumerate(self.lines):
if line.startswith("#"):
continue
ip = line.split()[0:1]
hostname = line.split()[1:2]
aliases = ','.join(line.split()[2:])
if self.ip and self.ip in ip:
self.ip_matches = True
self.found_on_line = lineno
self.log(self.ip + ' found on line')
if self.hostname and self.hostname in hostname:
self.hostname_matches = True
self.found_on_line = lineno
self.log(self.hostname + ' found on line')
# only look at aliases if we found hostname or ip
if self.hostname_matches or self.ip_matches:
if aliases:
self.log('aliases: ' + aliases)
self.has_aliases = True
if self.aliases and self.aliases == aliases:
self.aliases_matches = True
break
def full_entry_exists(self):
if self.has_aliases and not self.aliases_matches:
return False
return self.ip_matches and self.hostname_matches
def entry_exists(self):
return self.ip_matches or self.hostname_matches
def remove_entry(self):
self.lines.pop(self.found_on_line)
def add_entry(self):
aliases = ''
if self.aliases:
aliases = self.aliases.replace(',',' ')
host_entry = self.ip + " " + self.hostname + " " + aliases + "\n"
if self.entry_exists():
self.lines[self.found_on_line] = host_entry
else:
self.lines.extend(host_entry)
def write_changes(self):
tmpfd, tmpfile = tempfile.mkstemp()
f = os.fdopen(tmpfd,'wb')
f.writelines(self.lines)
f.close()
self.module.atomic_move(tmpfile, self.HOSTSFILE)
self.changed = True
def main():
module = AnsibleModule(
argument_spec = dict(
state=dict(default='present', choices=['present', 'absent'], type='str'),
ip=dict(default=None, type='str'),
hostname=dict(default=None, type='str'),
aliases=dict(default=None, type='str'),
),
supports_check_mode=True
)
result = {}
host = Host(module)
result['state'] = host.state
err = host.validate_has_hostname_on_present()
if err:
module.fail_json(msg=err)
err = host.validate_has_ip_or_hostname_on_absent()
if err:
module.fail_json(msg=err)
host.proceed_hosts_entries()
if host.state == 'present':
if not host.full_entry_exists():
host.log('Entry does not fully exist or may be missing.')
if module.check_mode:
module.exit_json(changed=True)
host.log('Adding or replacing entry.')
host.add_entry()
host.write_changes()
elif host.state == 'absent':
if host.entry_exists():
host.log('IP entry exists, removing.')
if module.check_mode:
module.exit_json(changed=True)
host.remove_entry()
host.write_changes()
result['changed'] = host.changed
module.exit_json(**result)
# include magic from lib/ansible/module_common.py
#<<INCLUDE_ANSIBLE_MODULE_COMMON>>
main()