/collections/ansible_collections/community/general/plugins/modules/system/cronvar.py
Python | 423 lines | 392 code | 13 blank | 18 comment | 11 complexity | 5fb9cfb93a87f3b5f5cde63b28522cff MD5 | raw file
- #!/usr/bin/python
- # -*- coding: utf-8 -*-
- # Copyright: (c) 2017, Ansible Project
- # GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
- # Cronvar Plugin: The goal of this plugin is to provide an idempotent
- # method for set cron variable values. It should play well with the
- # existing cron module as well as allow for manually added variables.
- # Each variable entered will be preceded with a comment describing the
- # variable so that it can be found later. This is required to be
- # present in order for this plugin to find/modify the variable
- # This module is based on the crontab module.
- from __future__ import absolute_import, division, print_function
- __metaclass__ = type
- DOCUMENTATION = r'''
- ---
- module: cronvar
- short_description: Manage variables in crontabs
- description:
- - Use this module to manage crontab variables.
- - This module allows you to create, update, or delete cron variable definitions.
- options:
- name:
- description:
- - Name of the crontab variable.
- type: str
- required: yes
- value:
- description:
- - The value to set this variable to.
- - Required if C(state=present).
- type: str
- insertafter:
- description:
- - If specified, the variable will be inserted after the variable specified.
- - Used with C(state=present).
- type: str
- insertbefore:
- description:
- - Used with C(state=present). If specified, the variable will be inserted
- just before the variable specified.
- type: str
- state:
- description:
- - Whether to ensure that the variable is present or absent.
- type: str
- choices: [ absent, present ]
- default: present
- user:
- description:
- - The specific user whose crontab should be modified.
- - This parameter defaults to C(root) when unset.
- type: str
- cron_file:
- description:
- - If specified, uses this file instead of an individual user's crontab.
- - Without a leading C(/), this is assumed to be in I(/etc/cron.d).
- - With a leading C(/), this is taken as absolute.
- type: str
- 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.
- type: bool
- default: no
- requirements:
- - cron
- author:
- - Doug Luce (@dougluce)
- '''
- EXAMPLES = r'''
- - name: Ensure entry like "EMAIL=doug@ansibmod.con.com" exists
- community.general.cronvar:
- name: EMAIL
- value: doug@ansibmod.con.com
- - name: Ensure a variable does not exist. This may remove any variable named "LEGACY"
- community.general.cronvar:
- name: LEGACY
- state: absent
- - name: Add a variable to a file under /etc/cron.d
- community.general.cronvar:
- name: LOGFILE
- value: /var/log/yum-autoupdate.log
- user: root
- cron_file: ansible_yum-autoupdate
- '''
- import os
- import platform
- import pwd
- import re
- import shlex
- import sys
- import tempfile
- from ansible.module_utils.basic import AnsibleModule
- from ansible.module_utils.six.moves import shlex_quote
- class CronVarError(Exception):
- pass
- class CronVar(object):
- """
- CronVar object to write variables to crontabs.
- 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.lines = None
- self.wordchars = ''.join(chr(x) for x in range(128) if chr(x) not in ('=', "'", '"',))
- self.cron_cmd = self.module.get_bin_path('crontab', required=True)
- if cron_file:
- self.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 Exception:
- raise CronVarError("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 CronVarError("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):
- self.module.debug('ansible: "%s"' % message)
- 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 remove_variable_file(self):
- try:
- os.unlink(self.cron_file)
- return True
- except OSError:
- # cron file does not exist
- return False
- except Exception:
- raise CronVarError("Unexpected error:", sys.exc_info()[0])
- def parse_for_var(self, line):
- lexer = shlex.shlex(line)
- lexer.wordchars = self.wordchars
- varname = lexer.get_token()
- is_env_var = lexer.get_token() == '='
- value = ''.join(lexer)
- if is_env_var:
- return (varname, value)
- raise CronVarError("Not a variable.")
- def find_variable(self, name):
- for l in self.lines:
- try:
- (varname, value) = self.parse_for_var(l)
- if varname == name:
- return value
- except CronVarError:
- pass
- return None
- def get_var_names(self):
- var_names = []
- for l in self.lines:
- try:
- var_name, dummy = self.parse_for_var(l)
- var_names.append(var_name)
- except CronVarError:
- pass
- return var_names
- def add_variable(self, name, value, insertbefore, insertafter):
- if insertbefore is None and insertafter is None:
- # Add the variable to the top of the file.
- self.lines.insert(0, "%s=%s" % (name, value))
- else:
- newlines = []
- for l in self.lines:
- try:
- varname, dummy = self.parse_for_var(l) # Throws if not a var line
- if varname == insertbefore:
- newlines.append("%s=%s" % (name, value))
- newlines.append(l)
- elif varname == insertafter:
- newlines.append(l)
- newlines.append("%s=%s" % (name, value))
- else:
- raise CronVarError # Append.
- except CronVarError:
- newlines.append(l)
- self.lines = newlines
- def remove_variable(self, name):
- self.update_variable(name, None, remove=True)
- def update_variable(self, name, value, remove=False):
- newlines = []
- for l in self.lines:
- try:
- varname, dummy = self.parse_for_var(l) # Throws if not a var line
- if varname != name:
- raise CronVarError # Append.
- if not remove:
- newlines.append("%s=%s" % (name, value))
- except CronVarError:
- newlines.append(l)
- self.lines = newlines
- def render(self):
- """
- Render a proper crontab
- """
- result = '\n'.join(self.lines)
- 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'" % (shlex_quote(self.user), shlex_quote(self.cron_cmd))
- elif platform.system() == 'AIX':
- return "%s -l %s" % (shlex_quote(self.cron_cmd), shlex_quote(self.user))
- elif platform.system() == 'HP-UX':
- return "%s %s %s" % (self.cron_cmd, '-l', shlex_quote(self.user))
- elif pwd.getpwuid(os.getuid())[0] != self.user:
- user = '-u %s' % shlex_quote(self.user)
- return "%s %s %s" % (self.cron_cmd, 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'" % (
- shlex_quote(self.user), shlex_quote(path), shlex_quote(self.user), self.cron_cmd, shlex_quote(path))
- elif pwd.getpwuid(os.getuid())[0] != self.user:
- user = '-u %s' % shlex_quote(self.user)
- return "%s %s %s" % (self.cron_cmd, user, shlex_quote(path))
- # ==================================================
- def main():
- # The following example playbooks:
- #
- # - community.general.cronvar: name="SHELL" value="/bin/bash"
- #
- # - name: Set the email
- # community.general.cronvar: name="EMAILTO" value="doug@ansibmod.con.com"
- #
- # - name: Get rid of the old new host variable
- # community.general.cronvar: name="NEW_HOST" state=absent
- #
- # Would produce:
- # SHELL = /bin/bash
- # EMAILTO = doug@ansibmod.con.com
- module = AnsibleModule(
- argument_spec=dict(
- name=dict(type='str', required=True),
- value=dict(type='str'),
- user=dict(type='str'),
- cron_file=dict(type='str'),
- insertafter=dict(type='str'),
- insertbefore=dict(type='str'),
- state=dict(type='str', default='present', choices=['absent', 'present']),
- backup=dict(type='bool', default=False),
- ),
- mutually_exclusive=[['insertbefore', 'insertafter']],
- supports_check_mode=False,
- )
- name = module.params['name']
- value = module.params['value']
- user = module.params['user']
- cron_file = module.params['cron_file']
- insertafter = module.params['insertafter']
- insertbefore = module.params['insertbefore']
- state = module.params['state']
- backup = module.params['backup']
- ensure_present = 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))
- cronvar = CronVar(module, user, cron_file)
- module.debug('cronvar instantiated - name: "%s"' % name)
- # --- user input validation ---
- if name is None and ensure_present:
- module.fail_json(msg="You must specify 'name' to insert a new cron variable")
- if value is None and ensure_present:
- module.fail_json(msg="You must specify 'value' to insert a new cron variable")
- if name is None and not ensure_present:
- module.fail_json(msg="You must specify 'name' to remove a cron variable")
- # if requested make a backup before making a change
- if backup:
- dummy, backup_file = tempfile.mkstemp(prefix='cronvar')
- cronvar.write(backup_file)
- if cronvar.cron_file and not name and not ensure_present:
- changed = cronvar.remove_job_file()
- module.exit_json(changed=changed, cron_file=cron_file, state=state)
- old_value = cronvar.find_variable(name)
- if ensure_present:
- if old_value is None:
- cronvar.add_variable(name, value, insertbefore, insertafter)
- changed = True
- elif old_value != value:
- cronvar.update_variable(name, value)
- changed = True
- else:
- if old_value is not None:
- cronvar.remove_variable(name)
- changed = True
- res_args = {
- "vars": cronvar.get_var_names(),
- "changed": changed
- }
- if changed:
- cronvar.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)
- if __name__ == '__main__':
- main()