From 3d65d6159fc0e6de2d17f13707d9daaaff103f60 Mon Sep 17 00:00:00 2001 From: Dane Summers Date: Fri, 5 Oct 2012 21:35:37 -0400 Subject: [PATCH] cron feature (w/o tests) --- library/cron | 222 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 222 insertions(+) create mode 100644 library/cron diff --git a/library/cron b/library/cron new file mode 100644 index 00000000000..71c3b832803 --- /dev/null +++ b/library/cron @@ -0,0 +1,222 @@ +#!/usr/bin/python +# -*- coding: utf-8 -*- +# +# (c) 2012, Dane Summers +# +# 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 . + +# 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. + +import re +import tempfile + +def get_jobs_file(user,tmpfile): + cmd = "crontab -l %s > %s" % (user,tmpfile) + cmd = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE) + (out, err) = cmd.communicate() + rc = cmd.returncode + return (rc, out, err) + +def install_jobs(user,tmpfile): + cmd = "crontab %s %s" % (user,tmpfile) + cmd = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE) + (out, err) = cmd.communicate() + rc = cmd.returncode + return (rc, out, err) + +def get_jobs(tmpfile): + lines = open(tmpfile).read().splitlines() + comment = None + jobs = [] + for l in lines: + if comment is not None: + jobs.append([comment,l]) + comment = None + elif re.match( r'#Ansible: ',l): + comment = re.sub( r'#Ansible: ', '', l) + return jobs + +def find_job(name,tmpfile): + jobs = get_jobs(tmpfile) + for j in jobs: + if j[0] == name: + return j + return [] + +def add_job(name,job,tmpfile): + cmd = "echo \"#Ansible: %s\n%s\" >> %s" % (name,job,tmpfile) + cmd = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE) + (out, err) = cmd.communicate() + rc = cmd.returncode + return (rc, out, err) + + +def update_job(name,job,tmpfile): + return _update_job(name,job,tmpfile,do_add_job) + +def do_add_job (lines, comment, job): + lines.append(comment) + lines.append(job) + +def remove_job(name,tmpfile): + return _update_job(name,"",tmpfile,do_remove_job) + +def do_remove_job(lines,comment,job): + return None + +def _update_job(name,job,tmpfile,addlinesfunction): + ansiblename="#Ansible: %s" % (name) + f = open(tmpfile) + lines = f.read().splitlines() + newlines = [] + comment = None + for l in lines: + if comment is not None: + addlinesfunction(newlines,comment,job) + comment = None + elif l == ansiblename: + comment = l + else: + newlines.append(l) + f.close() + f = open(tmpfile,'w') + for l in newlines: + f.write(l) + f.write('\n') + f.close() + return (0,"","") # TODO add some more error testing + +def main(): + # Options: + # name = name of cron job ( added as comment) + # user = defaults to the user of your connection + # job = cron time and command + # minute = minute when the job would run ( 0-59, *, */2, etc) + # hour = hour when the job would run ( 0-23, *, */2, etc) + # day = day of the month ( 1-31, *, */2, etc) + # month = month of the year ( 1-12, *, */2, etc) + # weekday = day of the week ( 0-7 Sunday thru Saturday, or 'mon', 'tue', etc) + # state = absent|present ( defaults to present) + # backup = make a backup of the cron before changing it. + # + # The minute/hour/day/month/weekday default to '*'. + # + # The following example playbooks: + # - action: cron name="check dirs" hour="5,2" job="ls -alh > /dev/null" + # - name: do the job + # action: name="do the job" cron hour="5,2" job="/some/dir/job.sh" + # - name: no job + # action: name="an old job" cron job="/some/dir/job.sh" state=absent + # + # Would produce: + # # Ansible: check dirs + # * * 5,2 * * ls -alh > /dev/null + # # Ansible: do the job + # * * 5,2 * * /some/dir/job.sh + + # Function: + # 1. dump the existing cron: + # crontab -l -u > /tmp/tmpfile + # 2. search for comment "^# Ansible: " followed by a cron. + # 3. if absent: remove if present (and say modified), otherwise return with no mod. + # 4. if present: if the same return no mod, if not present add (and say mod), if different add (and say mod) + # 5. Install new cron (if mod): + # crontab -u /tmp/tmpfile + # 6. return mod + + module = AnsibleModule( + argument_spec = dict( + name=dict(required=True), + user=dict(required=False), + job=dict(required=False), + state=dict(default='present', choices=['present', 'absent']), + backup=dict(default=False, choices=BOOLEANS), + minute=dict(default='*'), + hour=dict(default='*'), + day=dict(default='*'), + month=dict(default='*'), + weekday=dict(default='*') + ) + ) + + backup = module.boolean(module.params.get('backup', False)) + name = module.params['name'] + user = module.params['user'] + job = module.params['job'] + minute = module.params['minute'] + hour = module.params['hour'] + day = module.params['day'] + month = module.params['month'] + weekday = module.params['weekday'] + do_install = module.params['state'] == 'present' + changed = False + job = "%s %s %s %s %s %s" % (minute,hour,day,month,weekday,job) + + if not user: + user = "" + else: + user = "-u %s" % (user) + + rc, out, err, status = (0, None, None, None) + + if job is None and do_install: + module.fail_json(msg="You must specify 'job' to install a new cron job") + tmpfile = tempfile.NamedTemporaryFile() + (rc, out, err) = get_jobs_file(user,tmpfile.name) + if rc != 0 and rc != 1: # 1 can mean that there are no jobs. + module.fail_json(msg=err) + backupfile = tempfile.NamedTemporaryFile(prefix='crontab',delete=False) + (rc, out, err) = get_jobs_file(user,backupfile.name) + if rc != 0 and rc != 1: + module.fail_json(msg=err) + old_job = find_job(name,backupfile.name) + if do_install: + if len(old_job) == 0: + (rc, out, err) = add_job(name,job,tmpfile.name) + changed = True + if len(old_job) > 0 and old_job[1] != job: + (rc, out, err) = update_job(name,job,tmpfile.name) + changed = True + else: + if len(old_job) > 0: + (rc, out, err) = remove_job(name,tmpfile.name) + changed = True + if (rc != 0): + module.fail_json(msg=err) + if changed: + if backup: + module.backup_local(backupfile.name) + (rc, out, err) = install_jobs(user,tmpfile.name) + if (rc != 0): + module.fail_json(msg=err) + + jobnames = [] + for j in get_jobs(tmpfile.name): + jobnames.append(j[0]) + tmpfile.close() + backupfile.close() + if not backup: + module.exit_json(changed=changed,jobs=jobnames) + else: + module.exit_json(changed=changed,jobs=jobnames,backup=backupfile.name) + +# include magic from lib/ansible/module_common.py +#<> +main()