ansible/library/system/cron
2014-04-01 21:09:08 +10:00

521 lines
16 KiB
Python

#!/usr/bin/python
# -*- coding: utf-8 -*-
#
# (c) 2012, Dane Summers <dsummers@pinedesk.biz>
# (c) 2013, Mike Grozak <mike.grozak@gmail.com>
# (c) 2013, Patrick Callahan <pmc@patrickcallahan.com>
#
# 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/>.
#
# Cron Plugin: The goal of this plugin is to provide an indempotent method for
# setting up cron jobs on a host. The script will play well with other manually
# entered crons. Each cron job entered will be preceded with a comment
# describing the job so that it can be found later, which is required to be
# present in order for this plugin to find/modify the job.
#
# This module is based on python-crontab by Martin Owens.
#
DOCUMENTATION = """
---
module: cron
short_description: Manage cron.d and crontab entries.
description:
- Use this module to manage crontab entries. This module allows you to create named
crontab entries, update, or delete them.
- 'The module includes one line with the description of the crontab entry C("#Ansible: <name>")
corresponding to the "name" passed to the module, which is used by future ansible/module calls
to find/check the state.'
version_added: "0.9"
options:
name:
description:
- Description of a crontab entry.
required: false
default: null
user:
description:
- The specific user who's crontab should be modified.
required: false
default: root
job:
description:
- The command to execute. Required if state=present.
required: false
default: null
state:
description:
- Whether to ensure the job is present or absent.
required: false
default: present
choices: [ "present", "absent" ]
cron_file:
description:
- If specified, uses this file in cron.d instead of an individual user's crontab.
required: false
default: null
backup:
description:
- If set, create a backup of the crontab before it is modified.
The location of the backup is returned in the C(backup) variable by this module.
required: false
default: false
minute:
description:
- Minute when the job should run ( 0-59, *, */2, etc )
required: false
default: "*"
hour:
description:
- Hour when the job should run ( 0-23, *, */2, etc )
required: false
default: "*"
day:
description:
- Day of the month the job should run ( 1-31, *, */2, etc )
required: false
default: "*"
aliases: [ "dom" ]
month:
description:
- Month of the year the job should run ( 1-12, *, */2, etc )
required: false
default: "*"
weekday:
description:
- Day of the week that the job should run ( 0-7 for Sunday - Saturday, *, etc )
required: false
default: "*"
aliases: [ "dow" ]
reboot:
description:
- If the job should be run at reboot. This option is deprecated. Users should use special_time.
version_added: "1.0"
required: false
default: "no"
choices: [ "yes", "no" ]
special_time:
description:
- Special time specification nickname.
version_added: "1.3"
required: false
default: null
choices: [ "reboot", "yearly", "annually", "monthly", "weekly", "daily", "hourly" ]
requirements:
- cron
author: Dane Summers
updates: [ 'Mike Grozak', 'Patrick Callahan' ]
"""
EXAMPLES = '''
# Ensure a job that runs at 2 and 5 exists.
# Creates an entry like "* 5,2 * * ls -alh > /dev/null"
- cron: name="check dirs" hour="5,2" job="ls -alh > /dev/null"
# Ensure an old job is no longer present. Removes any job that is prefixed
# by "#Ansible: an old job" from the crontab
- cron: name="an old job" state=absent
# Creates an entry like "@reboot /some/job.sh"
- cron: name="a job for reboot" special_time=reboot job="/some/job.sh"
# Creates a cron file under /etc/cron.d
- cron: name="yum autoupdate" weekday="2" minute=0 hour=12
user="root" job="YUMINTERACTIVE=0 /usr/sbin/yum-autoupdate"
cron_file=ansible_yum-autoupdate
# Removes a cron file from under /etc/cron.d
- cron: cron_file=ansible_yum-autoupdate state=absent
'''
import os
import re
import tempfile
import platform
import pipes
CRONCMD = "/usr/bin/crontab"
class CronTabError(Exception):
pass
class CronTab(object):
"""
CronTab object to write time based crontab file
user - the user of the crontab (defaults to root)
cron_file - a cron file under /etc/cron.d
"""
def __init__(self, module, user=None, cron_file=None):
self.module = module
self.user = user
self.root = (os.getuid() == 0)
self.lines = None
self.ansible = "#Ansible: "
# select whether we dump additional debug info through syslog
self.syslogging = False
if cron_file:
self.cron_file = '/etc/cron.d/%s' % cron_file
else:
self.cron_file = None
self.read()
def read(self):
# Read in the crontab from the system
self.lines = []
if self.cron_file:
# read the cronfile
try:
f = open(self.cron_file, 'r')
self.lines = f.read().splitlines()
f.close()
except IOError, e:
# cron file does not exist
return
except:
raise CronTabError("Unexpected error:", sys.exc_info()[0])
else:
# using safely quoted shell for now, but this really should be two non-shell calls instead. FIXME
(rc, out, err) = self.module.run_command(self._read_user_execute(), use_unsafe_shell=True)
if rc != 0 and rc != 1: # 1 can mean that there are no jobs.
raise CronTabError("Unable to read crontab")
lines = out.splitlines()
count = 0
for l in lines:
if count > 2 or (not re.match( r'# DO NOT EDIT THIS FILE - edit the master and reinstall.', l) and
not re.match( r'# \(/tmp/.*installed on.*\)', l) and
not re.match( r'# \(.*version.*\)', l)):
self.lines.append(l)
count += 1
def log_message(self, message):
if self.syslogging:
syslog.syslog(syslog.LOG_NOTICE, 'ansible: "%s"' % message)
def is_empty(self):
if len(self.lines) == 0:
return True
else:
return False
def write(self, backup_file=None):
"""
Write the crontab to the system. Saves all information.
"""
if backup_file:
fileh = open(backup_file, 'w')
elif self.cron_file:
fileh = open(self.cron_file, 'w')
else:
filed, path = tempfile.mkstemp(prefix='crontab')
fileh = os.fdopen(filed, 'w')
fileh.write(self.render())
fileh.close()
# return if making a backup
if backup_file:
return
# Add the entire crontab back to the user crontab
if not self.cron_file:
# quoting shell args for now but really this should be two non-shell calls. FIXME
(rc, out, err) = self.module.run_command(self._write_execute(path), use_unsafe_shell=True)
os.unlink(path)
if rc != 0:
self.module.fail_json(msg=err)
def add_job(self, name, job):
# Add the comment
self.lines.append("%s%s" % (self.ansible, name))
# Add the job
self.lines.append("%s" % (job))
def update_job(self, name, job):
return self._update_job(name, job, self.do_add_job)
def do_add_job(self, lines, comment, job):
lines.append(comment)
lines.append("%s" % (job))
def remove_job(self, name):
return self._update_job(name, "", self.do_remove_job)
def do_remove_job(self, lines, comment, job):
return None
def remove_job_file(self):
try:
os.unlink(self.cron_file)
return True
except OSError, e:
# cron file does not exist
return False
except:
raise CronTabError("Unexpected error:", sys.exc_info()[0])
def find_job(self, name):
comment = None
for l in self.lines:
if comment is not None:
if comment == name:
return [comment, l]
else:
comment = None
elif re.match( r'%s' % self.ansible, l):
comment = re.sub( r'%s' % self.ansible, '', l)
return []
def get_cron_job(self,minute,hour,day,month,weekday,job,special):
if special:
if self.cron_file:
return "@%s %s %s" % (special, self.user, job)
else:
return "@%s %s" % (special, job)
else:
if self.cron_file:
return "%s %s %s %s %s %s %s" % (minute,hour,day,month,weekday,self.user,job)
else:
return "%s %s %s %s %s %s" % (minute,hour,day,month,weekday,job)
return None
def get_jobnames(self):
jobnames = []
for l in self.lines:
if re.match( r'%s' % self.ansible, l):
jobnames.append(re.sub( r'%s' % self.ansible, '', l))
return jobnames
def _update_job(self, name, job, addlinesfunction):
ansiblename = "%s%s" % (self.ansible, name)
newlines = []
comment = None
for l in self.lines:
if comment is not None:
addlinesfunction(newlines, comment, job)
comment = None
elif l == ansiblename:
comment = l
else:
newlines.append(l)
self.lines = newlines
if len(newlines) == 0:
return True
else:
return False # TODO add some more error testing
def render(self):
"""
Render this crontab as it would be in the crontab.
"""
crons = []
for cron in self.lines:
crons.append(cron)
result = '\n'.join(crons)
if result and result[-1] not in ['\n', '\r']:
result += '\n'
return result
def _read_user_execute(self):
"""
Returns the command line for reading a crontab
"""
user = ''
if self.user:
if platform.system() == 'SunOS':
return "su %s -c '%s -l'" % (pipes.quote(self.user), pipes.quote(CRONCMD))
elif platform.system() == 'HP-UX':
return "%s %s %s" % (CRONCMD , '-l', pipes.quote(self.user))
else:
user = '-u %s' % pipes.quote(self.user)
return "%s %s %s" % (CRONCMD , user, '-l')
def _write_execute(self, path):
"""
Return the command line for writing a crontab
"""
user = ''
if self.user:
if platform.system() in ['SunOS', 'HP-UX']:
return "chown %s %s ; su '%s' -c '%s %s'" % (pipes.quote(self.user), pipes.quote(path), pipes.quote(self.user), CRONCMD, pipes.quote(path))
else:
user = '-u %s' % pipes.quote(self.user)
return "%s %s %s" % (CRONCMD , user, pipes.quote(path))
#==================================================
def main():
# The following example playbooks:
#
# - cron: name="check dirs" hour="5,2" job="ls -alh > /dev/null"
#
# - name: do the job
# cron: name="do the job" hour="5,2" job="/some/dir/job.sh"
#
# - name: no job
# cron: name="an old job" state=absent
#
# Would produce:
# # Ansible: check dirs
# * * 5,2 * * ls -alh > /dev/null
# # Ansible: do the job
# * * 5,2 * * /some/dir/job.sh
module = AnsibleModule(
argument_spec = dict(
name=dict(required=False),
user=dict(required=False),
job=dict(required=False),
cron_file=dict(required=False),
state=dict(default='present', choices=['present', 'absent']),
backup=dict(default=False, type='bool'),
minute=dict(default='*'),
hour=dict(default='*'),
day=dict(aliases=['dom'], default='*'),
month=dict(default='*'),
weekday=dict(aliases=['dow'], default='*'),
reboot=dict(required=False, default=False, type='bool'),
special_time=dict(required=False,
default=None,
choices=["reboot", "yearly", "annually", "monthly", "weekly", "daily", "hourly"],
type='str')
),
supports_check_mode = False,
)
name = module.params['name']
user = module.params['user']
job = module.params['job']
cron_file = module.params['cron_file']
state = module.params['state']
backup = module.params['backup']
minute = module.params['minute']
hour = module.params['hour']
day = module.params['day']
month = module.params['month']
weekday = module.params['weekday']
reboot = module.params['reboot']
special_time = module.params['special_time']
do_install = state == 'present'
changed = False
res_args = dict()
# Ensure all files generated are only writable by the owning user. Primarily relevant for the cron_file option.
os.umask(022)
crontab = CronTab(module, user, cron_file)
if crontab.syslogging:
syslog.openlog('ansible-%s' % os.path.basename(__file__))
syslog.syslog(syslog.LOG_NOTICE, 'cron instantiated - name: "%s"' % name)
# --- user input validation ---
if (special_time or reboot) and \
(True in [(x != '*') for x in [minute, hour, day, month, weekday]]):
module.fail_json(msg="You must specify time and date fields or special time.")
if cron_file and do_install:
if not user:
module.fail_json(msg="To use file=... parameter you must specify user=... as well")
if reboot and special_time:
module.fail_json(msg="reboot and special_time are mutually exclusive")
if name is None and do_install:
module.fail_json(msg="You must specify 'name' to install a new cron job")
if job is None and do_install:
module.fail_json(msg="You must specify 'job' to install a new cron job")
if job and name is None and not do_install:
module.fail_json(msg="You must specify 'name' to remove a cron job")
if reboot:
if special_time:
module.fail_json(msg="reboot and special_time are mutually exclusive")
else:
special_time = "reboot"
# if requested make a backup before making a change
if backup:
(backuph, backup_file) = tempfile.mkstemp(prefix='crontab')
crontab.write(backup_file)
if crontab.cron_file and not name and not do_install:
changed = crontab.remove_job_file()
module.exit_json(changed=changed,cron_file=cron_file,state=state)
job = crontab.get_cron_job(minute, hour, day, month, weekday, job, special_time)
old_job = crontab.find_job(name)
if do_install:
if len(old_job) == 0:
crontab.add_job(name, job)
changed = True
if len(old_job) > 0 and old_job[1] != job:
crontab.update_job(name, job)
changed = True
else:
if len(old_job) > 0:
crontab.remove_job(name)
changed = True
res_args = dict(
jobs = crontab.get_jobnames(), changed = changed
)
if changed:
crontab.write()
# retain the backup only if crontab or cron file have changed
if backup:
if changed:
res_args['backup_file'] = backup_file
else:
os.unlink(backup_file)
if cron_file:
res_args['cron_file'] = cron_file
module.exit_json(**res_args)
# --- should never get here
module.exit_json(msg="Unable to execute cron task.")
# import module snippets
from ansible.module_utils.basic import *
main()