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#!/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>
# (c) 2015, Evan Kaufman <evan@digitalflophouse.com>
# (c) 2015, Luca Berruti <nadirio@gmail.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 idempotent 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 and environment variables entries. This module allows
you to create environment variables and named crontab entries, update, or delete them.
- 'When crontab jobs are managed: 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. The "name"
parameter should be unique, and changing the "name" value will result in a new cron
task being created (or a different one being removed).'
- 'When environment variables are managed: no comment line is added, but, when the module
needs to find/check the state, it uses the "name" parameter to find the environment
variable definition line.'
- 'When using symbols such as %, they must be properly escaped.'
version_added: "0.9"
options:
name:
description:
- Description of a crontab entry or, if env is set, the name of environment variable.
Required if state=absent. Note that if name is not set and state=present, then a
new crontab entry will always be created, regardless of existing ones.
default: null
required: false
user:
description:
- The specific user whose crontab should be modified.
required: false
default: root
job:
description:
- The command to execute or, if env is set, the value of environment variable.
Required if state=present.
required: false
aliases: ['value']
default: null
state:
description:
- Whether to ensure the job or environment variable is present or absent.
required: false
default: present
choices: [ "present", "absent" ]
cron_file:
description:
- If specified, uses this file instead of an individual user's crontab.
If this is a relative path, it is interpreted with respect to
/etc/cron.d. (If it is absolute, it will typically be /etc/crontab).
To use the C(cron_file) parameter you must specify the C(user) as well.
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_file) variable by this module.
required: false
choices: [ "yes", "no" ]
default: no
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 ( 0-6 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" ]
disabled:
description:
- If the job should be disabled (commented out) in the crontab. Only has effect if state=present
version_added: "2.0"
required: false
default: false
env:
description:
- If set, manages a crontab's environment variable. New variables are added on top of crontab.
"name" and "value" parameters are the name and the value of environment variable.
version_added: "2.1"
required: false
default: "no"
choices: [ "yes", "no" ]
insertafter:
description:
- Used with C(state=present) and C(env). If specified, the environment variable will be
inserted after the declaration of specified environment variable.
version_added: "2.1"
required: false
default: null
insertbefore:
description:
- Used with C(state=present) and C(env). If specified, the environment variable will be
inserted before the declaration of specified environment variable.
version_added: "2.1"
required: false
default: null
requirements:
- cron
author:
- "Dane Summers (@dsummersl)"
- 'Mike Grozak'
- 'Patrick Callahan'
- 'Evan Kaufman (@EvanK)'
- 'Luca Berruti (@lberruti)'
"""
EXAMPLES = '''
# Ensure a job that runs at 2 and 5 exists.
# Creates an entry like "0 5,2 * * ls -alh > /dev/null"
- cron: name="check dirs" minute="0" 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 an entry like "PATH=/opt/bin" on top of crontab
- cron: name=PATH env=yes value=/opt/bin
# Creates an entry like "APP_HOME=/srv/app" and insert it after PATH
# declaration
- cron: name=APP_HOME env=yes value=/srv/app insertafter=PATH
# 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: name="yum autoupdate" cron_file=ansible_yum-autoupdate state=absent
# Removes "APP_HOME" environment variable from crontab
- cron: name=APP_HOME env=yes state=absent
'''
import os
import pwd
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, or an absolute path
"""
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: "
if cron_file:
if os.path.isabs(cron_file):
self.cron_file = cron_file
else:
self.cron_file = os.path.join('/etc/cron.d', 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:
# 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 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')
os.chmod(path, int('0644', 8))
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 add_env(self, decl, insertafter=None, insertbefore=None):
if not (insertafter or insertbefore):
self.lines.insert(0, decl)
return
if insertafter:
other_name = insertafter
elif insertbefore:
other_name = insertbefore
other_decl = self.find_env(other_name)
if len(other_decl) > 0:
if insertafter:
index = other_decl[0]+1
elif insertbefore:
index = other_decl[0]
self.lines.insert(index, decl)
return
self.module.fail_json(msg="Variable named '%s' not found." % other_name)
def update_env(self, name, decl):
return self._update_env(name, decl, self.do_add_env)
def do_add_env(self, lines, decl):
lines.append(decl)
def remove_env(self, name):
return self._update_env(name, '', self.do_remove_env)
def do_remove_env(self, lines, decl):
return None
def remove_job_file(self):
try:
os.unlink(self.cron_file)
return True
except OSError:
# 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 find_env(self, name):
for index, l in enumerate(self.lines):
if re.match( r'^%s=' % name, l):
return [index, l]
return []
def get_cron_job(self,minute,hour,day,month,weekday,job,special,disabled):
# normalize any leading/trailing newlines (ansible/ansible-modules-core#3791)
if job:
job = job.strip('\r\n')
else:
job = ''
if disabled:
disable_prefix = '#'
else:
disable_prefix = ''
if special:
if self.cron_file:
return "%s@%s %s %s" % (disable_prefix, special, self.user, job)
else:
return "%s@%s %s" % (disable_prefix, special, job)
else:
if self.cron_file:
return "%s%s %s %s %s %s %s %s" % (disable_prefix,minute,hour,day,month,weekday,self.user,job)
else:
return "%s%s %s %s %s %s %s" % (disable_prefix,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 get_envnames(self):
envnames = []
for l in self.lines:
if re.match( r'^\S+=' , l):
envnames.append(l.split('=')[0])
return envnames
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 _update_env(self, name, decl, addenvfunction):
newlines = []
for l in self.lines:
if re.match( r'^%s=' % name, l):
addenvfunction(newlines, decl)
else:
newlines.append(l)
self.lines = newlines
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() == 'AIX':
return "%s -l %s" % (pipes.quote(CRONCMD), pipes.quote(self.user))
elif platform.system() == 'HP-UX':
return "%s %s %s" % (CRONCMD , '-l', pipes.quote(self.user))
elif pwd.getpwuid(os.getuid())[0] != self.user:
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', 'AIX']:
return "chown %s %s ; su '%s' -c '%s %s'" % (pipes.quote(self.user), pipes.quote(path), pipes.quote(self.user), CRONCMD, pipes.quote(path))
elif pwd.getpwuid(os.getuid())[0] != self.user:
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
#
# - name: sets env
# cron: name="PATH" env=yes value="/bin:/usr/bin"
#
# Would produce:
# PATH=/bin:/usr/bin
# # 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, aliases=['value']),
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'),
disabled=dict(default=False, type='bool'),
env=dict(required=False, type='bool'),
insertafter=dict(required=False),
insertbefore=dict(required=False),
),
supports_check_mode = True,
mutually_exclusive=[
['reboot', 'special_time'],
['insertafter', 'insertbefore'],
]
)
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']
disabled = module.params['disabled']
env = module.params['env']
insertafter = module.params['insertafter']
insertbefore = module.params['insertbefore']
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(int('022', 8))
crontab = CronTab(module, user, cron_file)
module.debug('cron instantiated - name: "%s"' % name)
if module._diff:
diff = dict()
diff['before'] = crontab.render()
if crontab.cron_file:
diff['before_header'] = crontab.cron_file
else:
if crontab.user:
diff['before_header'] = 'crontab for user "%s"' % crontab.user
else:
diff['before_header'] = 'crontab'
# --- 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 cron_file=... parameter you must specify user=... as well")
if job is None and do_install:
module.fail_json(msg="You must specify 'job' to install a new cron job or variable")
if (insertafter or insertbefore) and not env and do_install:
module.fail_json(msg="Insertafter and insertbefore parameters are valid only with env=yes")
if reboot:
special_time = "reboot"
# if requested make a backup before making a change
if backup and not module.check_mode:
(backuph, backup_file) = tempfile.mkstemp(prefix='crontab')
crontab.write(backup_file)
if crontab.cron_file and not name and not do_install:
if module._diff:
diff['after'] = ''
diff['after_header'] = '/dev/null'
else:
diff = dict()
if module.check_mode:
changed = os.path.isfile(crontab.cron_file)
else:
changed = crontab.remove_job_file()
module.exit_json(changed=changed,cron_file=cron_file,state=state,diff=diff)
if env:
if ' ' in name:
module.fail_json(msg="Invalid name for environment variable")
decl = '%s="%s"' % (name, job)
old_decl = crontab.find_env(name)
if do_install:
if len(old_decl) == 0:
crontab.add_env(decl, insertafter, insertbefore)
changed = True
if len(old_decl) > 0 and old_decl[1] != decl:
crontab.update_env(name, decl)
changed = True
else:
if len(old_decl) > 0:
crontab.remove_env(name)
changed = True
else:
job = crontab.get_cron_job(minute, hour, day, month, weekday, job, special_time, disabled)
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(),
envs = crontab.get_envnames(),
changed = changed
)
if changed:
if not module.check_mode:
crontab.write()
if module._diff:
diff['after'] = crontab.render()
if crontab.cron_file:
diff['after_header'] = crontab.cron_file
else:
if crontab.user:
diff['after_header'] = 'crontab for user "%s"' % crontab.user
else:
diff['after_header'] = 'crontab'
res_args['diff'] = diff
# retain the backup only if crontab or cron file have changed
if backup:
if changed:
res_args['backup_file'] = backup_file
else:
if not module.check_mode:
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()
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