#!/usr/bin/python # -*- coding: utf-8 -*- # (c) 2013, Darryl Stoflet # GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt) from __future__ import absolute_import, division, print_function __metaclass__ = type from collections import namedtuple DOCUMENTATION = ''' --- module: monit short_description: Manage the state of a program monitored via Monit description: - Manage the state of a program monitored via I(Monit) options: name: description: - The name of the I(monit) program/process to manage required: true state: description: - The state of service required: true choices: [ "present", "started", "stopped", "restarted", "monitored", "unmonitored", "reloaded" ] timeout: description: - If there are pending actions for the service monitored by monit, then Ansible will check for up to this many seconds to verify the requested action has been performed. Ansible will sleep for five seconds between each check. default: 300 author: "Darryl Stoflet (@dstoflet)" ''' EXAMPLES = ''' - name: Manage the state of program httpd to be in started state community.general.monit: name: httpd state: started ''' import time import re from ansible.module_utils.basic import AnsibleModule STATE_COMMAND_MAP = { 'stopped': 'stop', 'started': 'start', 'monitored': 'monitor', 'unmonitored': 'unmonitor', 'restarted': 'restart' } MIN_VERSION = (5, 21) ALL_STATUS = [ 'missing', 'ok', 'not_monitored', 'initializing', 'does_not_exist' ] class StatusValue(namedtuple("Status", "value, is_pending")): MISSING = 0 OK = 1 NOT_MONITORED = 2 INITIALIZING = 3 DOES_NOT_EXIST = 4 def __new__(cls, value, is_pending=False): return super(StatusValue, cls).__new__(cls, value, is_pending) def pending(self): return StatusValue(self.value, True) def __getattr__(self, item): if item in ('is_%s' % status for status in ALL_STATUS): return self.value == getattr(self, item[3:].upper()) class Status(object): MISSING = StatusValue(StatusValue.MISSING) OK = StatusValue(StatusValue.OK) NOT_MONITORED = StatusValue(StatusValue.NOT_MONITORED) INITIALIZING = StatusValue(StatusValue.INITIALIZING) DOES_NOT_EXIST = StatusValue(StatusValue.DOES_NOT_EXIST) class Monit(object): def __init__(self, module, monit_bin_path, service_name, timeout): self.module = module self.monit_bin_path = monit_bin_path self.process_name = service_name self.timeout = timeout self._monit_version = None self._sleep_time = 5 def monit_version(self): if self._monit_version is None: rc, out, err = self.module.run_command('%s -V' % self.monit_bin_path, check_rc=True) version_line = out.split('\n')[0] version = re.search(r"[0-9]+\.[0-9]+", version_line).group().split('.') # Use only major and minor even if there are more these should be enough self._monit_version = int(version[0]), int(version[1]) return self._monit_version def check_version(self): if self.monit_version() < MIN_VERSION: min_version = '.'.join(str(v) for v in MIN_VERSION) self.module.fail_json(msg='Monit version not compatible with module. Install version >= %s' % min_version) def get_status(self): """Return the status of the process in monit.""" command = '%s status %s -B' % (self.monit_bin_path, self.process_name) rc, out, err = self.module.run_command(command, check_rc=True) return self._parse_status(out) def _parse_status(self, output): if "Process '%s'" % self.process_name not in output: return Status.MISSING status_val = re.findall(r"^\s*status\s*([\w\- ]+)", output, re.MULTILINE) if not status_val: self.module.fail_json(msg="Unable to find process status") status_val = status_val[0].strip().upper() if ' - ' not in status_val: status_val = status_val.replace(' ', '_') return getattr(Status, status_val) else: status_val, substatus = status_val.split(' - ') action, state = substatus.split() if action in ['START', 'INITIALIZING', 'RESTART', 'MONITOR']: status = Status.OK else: status = Status.NOT_MONITORED if state == 'pending': status = status.pending() return status def is_process_present(self): rc, out, err = self.module.run_command('%s summary -B' % (self.monit_bin_path), check_rc=True) return bool(re.findall(r'\b%s\b' % self.process_name, out)) def is_process_running(self): return self.get_status().is_ok def run_command(self, command): """Runs a monit command, and returns the new status.""" return self.module.run_command('%s %s %s' % (self.monit_bin_path, command, self.process_name), check_rc=True) def wait_for_monit_to_stop_pending(self, state): """Fails this run if there is no status or it's pending/initializing for timeout""" timeout_time = time.time() + self.timeout running_status = self.get_status() waiting_status = [ StatusValue.MISSING, StatusValue.INITIALIZING, StatusValue.DOES_NOT_EXIST, ] while running_status.is_pending or (running_status.value in waiting_status): if time.time() >= timeout_time: self.module.fail_json( msg='waited too long for "pending", or "initiating" status to go away ({0})'.format( running_status ), state=state ) if self._sleep_time: time.sleep(self._sleep_time) running_status = self.get_status() def reload(self): rc, out, err = self.module.run_command('%s reload' % self.monit_bin_path) if rc != 0: self.module.fail_json(msg='monit reload failed', stdout=out, stderr=err) self.wait_for_monit_to_stop_pending('reloaded') self.module.exit_json(changed=True, name=self.process_name, state='reloaded') def present(self): self.run_command('reload') if not self.is_process_present(): self.wait_for_monit_to_stop_pending('present') self.module.exit_json(changed=True, name=self.process_name, state='present') def change_state(self, state, expected_status, invert_expected=None): self.run_command(STATE_COMMAND_MAP[state]) status = self.get_status() status_match = status.value == expected_status.value if invert_expected: status_match = not status_match if status_match: self.module.exit_json(changed=True, name=self.process_name, state=state) self.module.fail_json(msg='%s process not %s' % (self.process_name, state), status=repr(status)) def stop(self): self.change_state('stopped', Status.NOT_MONITORED) def unmonitor(self): self.change_state('unmonitored', Status.NOT_MONITORED) def restart(self): self.change_state('restarted', Status.OK) def start(self): self.change_state('started', Status.OK) def monitor(self): self.change_state('monitored', Status.NOT_MONITORED, invert_expected=True) def main(): arg_spec = dict( name=dict(required=True), timeout=dict(default=300, type='int'), state=dict(required=True, choices=['present', 'started', 'restarted', 'stopped', 'monitored', 'unmonitored', 'reloaded']) ) module = AnsibleModule(argument_spec=arg_spec, supports_check_mode=True) name = module.params['name'] state = module.params['state'] timeout = module.params['timeout'] monit = Monit(module, module.get_bin_path('monit', True), name, timeout) monit.check_version() def exit_if_check_mode(): if module.check_mode: module.exit_json(changed=True) if state == 'reloaded': exit_if_check_mode() monit.reload() present = monit.is_process_present() if not present and not state == 'present': module.fail_json(msg='%s process not presently configured with monit' % name, name=name, state=state) if state == 'present': if present: module.exit_json(changed=False, name=name, state=state) exit_if_check_mode() monit.present() monit.wait_for_monit_to_stop_pending(state) running = monit.is_process_running() if running and state in ['started', 'monitored']: module.exit_json(changed=False, name=name, state=state) if running and state == 'stopped': exit_if_check_mode() monit.stop() if running and state == 'unmonitored': exit_if_check_mode() monit.unmonitor() elif state == 'restarted': exit_if_check_mode() monit.restart() elif not running and state == 'started': exit_if_check_mode() monit.start() elif not running and state == 'monitored': exit_if_check_mode() monit.monitor() module.exit_json(changed=False, name=name, state=state) if __name__ == '__main__': main()