#!/usr/bin/python # -*- coding: utf-8 -*- # Copyright: (c) 2018, Martin Migasiewicz # 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 DOCUMENTATION = r''' --- module: launchd author: - Martin Migasiewicz (@martinm82) short_description: Manage macOS services version_added: 1.0.0 description: - Manage launchd services on target macOS hosts. options: name: description: - Name of the service. type: str required: true state: description: - C(started)/C(stopped) are idempotent actions that will not run commands unless necessary. - Launchd does not support C(restarted) nor C(reloaded) natively. These will trigger a stop/start (restarted) or an unload/load (reloaded). - C(restarted) unloads and loads the service before start to ensure that the latest job definition (plist) is used. - C(reloaded) unloads and loads the service to ensure that the latest job definition (plist) is used. Whether a service is started or stopped depends on the content of the definition file. type: str choices: [ reloaded, restarted, started, stopped, unloaded ] enabled: description: - Whether the service should start on boot. - B(At least one of state and enabled are required.) type: bool force_stop: description: - Whether the service should not be restarted automatically by launchd. - Services might have the 'KeepAlive' attribute set to true in a launchd configuration. In case this is set to true, stopping a service will cause that launchd starts the service again. - Set this option to C(yes) to let this module change the 'KeepAlive' attribute to false. type: bool default: no notes: - A user must privileged to manage services using this module. requirements: - A system managed by launchd - The plistlib python library ''' EXAMPLES = r''' - name: Make sure spotify webhelper is started community.general.launchd: name: com.spotify.webhelper state: started - name: Deploy custom memcached job definition template: src: org.memcached.plist.j2 dest: /Library/LaunchDaemons/org.memcached.plist - name: Run memcached community.general.launchd: name: org.memcached state: started - name: Stop memcached community.general.launchd: name: org.memcached state: stopped - name: Stop memcached community.general.launchd: name: org.memcached state: stopped force_stop: yes - name: Restart memcached community.general.launchd: name: org.memcached state: restarted - name: Unload memcached community.general.launchd: name: org.memcached state: unloaded ''' RETURN = r''' status: description: Metadata about service status returned: always type: dict sample: { "current_pid": "-", "current_state": "stopped", "previous_pid": "82636", "previous_state": "running" } ''' import os import plistlib from abc import ABCMeta, abstractmethod from time import sleep from ansible.module_utils.basic import AnsibleModule from ansible.module_utils._text import to_native class ServiceState: UNKNOWN = 0 LOADED = 1 STOPPED = 2 STARTED = 3 UNLOADED = 4 @staticmethod def to_string(state): strings = { ServiceState.UNKNOWN: 'unknown', ServiceState.LOADED: 'loaded', ServiceState.STOPPED: 'stopped', ServiceState.STARTED: 'started', ServiceState.UNLOADED: 'unloaded' } return strings[state] class Plist: def __init__(self, module, service): self.__changed = False self.__service = service state, pid, dummy, dummy = LaunchCtlList(module, self.__service).run() # Check if readPlist is available or not self.old_plistlib = hasattr(plistlib, 'readPlist') self.__file = self.__find_service_plist(self.__service) if self.__file is None: msg = 'Unable to infer the path of %s service plist file' % self.__service if pid is None and state == ServiceState.UNLOADED: msg += ' and it was not found among active services' module.fail_json(msg=msg) self.__update(module) @staticmethod def __find_service_plist(service_name): """Finds the plist file associated with a service""" launchd_paths = [ os.path.join(os.getenv('HOME'), 'Library/LaunchAgents'), '/Library/LaunchAgents', '/Library/LaunchDaemons', '/System/Library/LaunchAgents', '/System/Library/LaunchDaemons' ] for path in launchd_paths: try: files = os.listdir(path) except OSError: continue filename = '%s.plist' % service_name if filename in files: return os.path.join(path, filename) return None def __update(self, module): self.__handle_param_enabled(module) self.__handle_param_force_stop(module) def __read_plist_file(self, module): service_plist = {} if self.old_plistlib: return plistlib.readPlist(self.__file) # readPlist is deprecated in Python 3 and onwards try: with open(self.__file, 'rb') as plist_fp: service_plist = plistlib.load(plist_fp) except Exception as e: module.fail_json(msg="Failed to read plist file " "%s due to %s" % (self.__file, to_native(e))) return service_plist def __write_plist_file(self, module, service_plist=None): if not service_plist: service_plist = {} if self.old_plistlib: plistlib.writePlist(service_plist, self.__file) return # writePlist is deprecated in Python 3 and onwards try: with open(self.__file, 'wb') as plist_fp: plistlib.dump(service_plist, plist_fp) except Exception as e: module.fail_json(msg="Failed to write to plist file " " %s due to %s" % (self.__file, to_native(e))) def __handle_param_enabled(self, module): if module.params['enabled'] is not None: service_plist = self.__read_plist_file(module) # Enable/disable service startup at boot if requested # Launchctl does not expose functionality to set the RunAtLoad # attribute of a job definition. So we parse and modify the job # definition plist file directly for this purpose. if module.params['enabled'] is not None: enabled = service_plist.get('RunAtLoad', False) if module.params['enabled'] != enabled: service_plist['RunAtLoad'] = module.params['enabled'] # Update the plist with one of the changes done. if not module.check_mode: self.__write_plist_file(module, service_plist) self.__changed = True def __handle_param_force_stop(self, module): if module.params['force_stop'] is not None: service_plist = self.__read_plist_file(module) # Set KeepAlive to false in case force_stop is defined to avoid # that the service gets restarted when stopping was requested. if module.params['force_stop'] is not None: keep_alive = service_plist.get('KeepAlive', False) if module.params['force_stop'] and keep_alive: service_plist['KeepAlive'] = not module.params['force_stop'] # Update the plist with one of the changes done. if not module.check_mode: self.__write_plist_file(module, service_plist) self.__changed = True def is_changed(self): return self.__changed def get_file(self): return self.__file class LaunchCtlTask(object): __metaclass__ = ABCMeta WAITING_TIME = 5 # seconds def __init__(self, module, service, plist): self._module = module self._service = service self._plist = plist self._launch = self._module.get_bin_path('launchctl', True) def run(self): """Runs a launchd command like 'load', 'unload', 'start', 'stop', etc. and returns the new state and pid. """ self.runCommand() return self.get_state() @abstractmethod def runCommand(self): pass def get_state(self): rc, out, err = self._launchctl("list") if rc != 0: self._module.fail_json( msg='Failed to get status of %s' % (self._launch)) state = ServiceState.UNLOADED service_pid = "-" status_code = None for line in out.splitlines(): if line.strip(): pid, last_exit_code, label = line.split('\t') if label.strip() == self._service: service_pid = pid status_code = last_exit_code # From launchctl man page: # If the number [...] is negative, it represents the # negative of the signal which killed the job. Thus, # "-15" would indicate that the job was terminated with # SIGTERM. if last_exit_code not in ['0', '-2', '-3', '-9', '-15']: # Something strange happened and we have no clue in # which state the service is now. Therefore we mark # the service state as UNKNOWN. state = ServiceState.UNKNOWN elif pid != '-': # PID seems to be an integer so we assume the service # is started. state = ServiceState.STARTED else: # Exit code is 0 and PID is not available so we assume # the service is stopped. state = ServiceState.STOPPED break return (state, service_pid, status_code, err) def start(self): rc, out, err = self._launchctl("start") # Unfortunately launchd does not wait until the process really started. sleep(self.WAITING_TIME) return (rc, out, err) def stop(self): rc, out, err = self._launchctl("stop") # Unfortunately launchd does not wait until the process really stopped. sleep(self.WAITING_TIME) return (rc, out, err) def restart(self): # TODO: check for rc, out, err self.stop() return self.start() def reload(self): # TODO: check for rc, out, err self.unload() return self.load() def load(self): return self._launchctl("load") def unload(self): return self._launchctl("unload") def _launchctl(self, command): service_or_plist = self._plist.get_file() if command in [ 'load', 'unload'] else self._service if command in ['start', 'stop'] else "" rc, out, err = self._module.run_command( '%s %s %s' % (self._launch, command, service_or_plist)) if rc != 0: msg = "Unable to %s '%s' (%s): '%s'" % ( command, self._service, self._plist.get_file(), err) self._module.fail_json(msg=msg) return (rc, out, err) class LaunchCtlStart(LaunchCtlTask): def __init__(self, module, service, plist): super(LaunchCtlStart, self).__init__(module, service, plist) def runCommand(self): state, dummy, dummy, dummy = self.get_state() if state in (ServiceState.STOPPED, ServiceState.LOADED): self.reload() self.start() elif state == ServiceState.STARTED: # In case the service is already in started state but the # job definition was changed we need to unload/load the # service and start the service again. if self._plist.is_changed(): self.reload() self.start() elif state == ServiceState.UNLOADED: self.load() self.start() elif state == ServiceState.UNKNOWN: # We are in an unknown state, let's try to reload the config # and start the service again. self.reload() self.start() class LaunchCtlStop(LaunchCtlTask): def __init__(self, module, service, plist): super(LaunchCtlStop, self).__init__(module, service, plist) def runCommand(self): state, dummy, dummy, dummy = self.get_state() if state == ServiceState.STOPPED: # In case the service is stopped and we might later decide # to start it, we need to reload the job definition by # forcing an unload and load first. # Afterwards we need to stop it as it might have been # started again (KeepAlive or RunAtLoad). if self._plist.is_changed(): self.reload() self.stop() elif state in (ServiceState.STARTED, ServiceState.LOADED): if self._plist.is_changed(): self.reload() self.stop() elif state == ServiceState.UNKNOWN: # We are in an unknown state, let's try to reload the config # and stop the service gracefully. self.reload() self.stop() class LaunchCtlReload(LaunchCtlTask): def __init__(self, module, service, plist): super(LaunchCtlReload, self).__init__(module, service, plist) def runCommand(self): state, dummy, dummy, dummy = self.get_state() if state == ServiceState.UNLOADED: # launchd throws an error if we do an unload on an already # unloaded service. self.load() else: self.reload() class LaunchCtlUnload(LaunchCtlTask): def __init__(self, module, service, plist): super(LaunchCtlUnload, self).__init__(module, service, plist) def runCommand(self): state, dummy, dummy, dummy = self.get_state() self.unload() class LaunchCtlRestart(LaunchCtlReload): def __init__(self, module, service, plist): super(LaunchCtlRestart, self).__init__(module, service, plist) def runCommand(self): super(LaunchCtlRestart, self).runCommand() self.start() class LaunchCtlList(LaunchCtlTask): def __init__(self, module, service): super(LaunchCtlList, self).__init__(module, service, None) def runCommand(self): # Do nothing, the list functionality is done by the # base class run method. pass def main(): module = AnsibleModule( argument_spec=dict( name=dict(type='str', required=True), state=dict(type='str', choices=['reloaded', 'restarted', 'started', 'stopped', 'unloaded']), enabled=dict(type='bool'), force_stop=dict(type='bool', default=False), ), supports_check_mode=True, required_one_of=[ ['state', 'enabled'], ], ) service = module.params['name'] action = module.params['state'] rc = 0 out = err = '' result = { 'name': service, 'changed': False, 'status': {}, } # We will tailor the plist file in case one of the options # (enabled, force_stop) was specified. plist = Plist(module, service) result['changed'] = plist.is_changed() # Gather information about the service to be controlled. state, pid, dummy, dummy = LaunchCtlList(module, service).run() result['status']['previous_state'] = ServiceState.to_string(state) result['status']['previous_pid'] = pid # Map the actions to specific tasks tasks = { 'started': LaunchCtlStart(module, service, plist), 'stopped': LaunchCtlStop(module, service, plist), 'restarted': LaunchCtlRestart(module, service, plist), 'reloaded': LaunchCtlReload(module, service, plist), 'unloaded': LaunchCtlUnload(module, service, plist) } status_code = '0' # Run the requested task if not module.check_mode: state, pid, status_code, err = tasks[action].run() result['status']['current_state'] = ServiceState.to_string(state) result['status']['current_pid'] = pid result['status']['status_code'] = status_code result['status']['error'] = err if (result['status']['current_state'] != result['status']['previous_state'] or result['status']['current_pid'] != result['status']['previous_pid']): result['changed'] = True if module.check_mode: result['changed'] = True module.exit_json(**result) if __name__ == '__main__': main()