class TimeWindow(SimplePredicate):
"""
Predicate for comparing current time to start/stop times.
It will set the 'met' value based on start > current_time > stop.
"""
def __init__(self,
comp_name,
begin=None,
end=None,
weekdays=None,
operational=False,
parent=None,
interval=5):
"""
:type comp_name: str
:type begin: str or None
:type end: str or None
:type weekdays: str or None
:type operational: bool
:type parent: str or None
:type interval: int or float
"""
SimplePredicate.__init__(self,
comp_name,
operational=operational,
parent=parent)
self.begin = self.get_datetime_object(begin)
self.end = self.get_datetime_object(end)
self.day_range = self.parse_range(weekdays)
self.interval = interval
self._log = logging.getLogger(
'sent.{0}.pred.timewin'.format(comp_name))
self._log.info('Registered {0}'.format(self))
self._operate = ThreadSafeObject(True)
self._thread = Thread(target=self._run_loop, name=str(self))
self._thread.daemon = True
self._started = False
def weekday(self):
"""
:rtype: int
0=Monday, 1=Tuesday, etc.
"""
return datetime.date.today().weekday()
def start(self):
if self._started is False:
self._log.debug('Starting {0}'.format(self))
self._started = True
self._thread.start()
self._block_until_started()
else:
self._log.debug('Already started {0}'.format(self))
def stop(self):
if self._started is True:
self._log.info('Stopping {0}'.format(self))
self._started = False
self._operate.set_value(False)
self._thread.join()
self._log.info('{0} stopped'.format(self))
else:
self._log.debug('Already stopped {0}'.format(self))
def _run_loop(self):
while self._operate == True:
self._process_met()
sleep(self.interval)
self._log.info('Done comparing times.')
def _process_met(self):
results = []
if self.begin is not None:
compare_to_begin = self._get_comparison(self.begin)
results.append(self.begin < compare_to_begin)
if self.end is not None:
compare_to_end = self._get_comparison(self.end)
results.append(compare_to_end < self.end)
if self.day_range is not None:
results.append(self.weekday() in self.day_range)
if not results:
results.append(False)
self.set_met(all(results)) # every comparison returned True
def _get_comparison(self, obj):
if isinstance(obj, datetime.datetime):
return datetime.datetime.now()
elif isinstance(obj, datetime.time):
return datetime.datetime.now().time()
@staticmethod
def get_datetime_object(data):
"""
Create datetime object from string value
:type data: str or None
:rtype: datetime.datetime or datetime.time or None
"""
if data is None:
return
dt_object = None
dt_dict = TimeWindow.create_datetime_dict(data)
try:
# All of year, month and day are not None
if all([
dt_dict.get(i, None) is not None
for i in ('year', 'month', 'day')
]):
dt_object = datetime.datetime(year=dt_dict['year'],
month=dt_dict['month'],
day=dt_dict['day'],
hour=dt_dict['hour'],
minute=dt_dict['minute'],
microsecond=0)
if dt_dict['second'] is not None:
dt_object = dt_object.replace(second=dt_dict['second'])
# both hour and minute are not None
elif all(
[dt_dict.get(i, None) is not None
for i in ('hour', 'minute')]):
dt_object = datetime.time(hour=dt_dict['hour'],
minute=dt_dict['minute'],
microsecond=0)
if dt_dict.get('second', None) is not None:
dt_object = dt_object.replace(second=dt_dict['second'])
else:
logging.getLogger('PredicateTime').error(
'data "{0}" did not match regex. This will result in the '
'paramter returning as None. The predicate will never be '
'met for this parameter. '.format(data))
except (ValueError, TypeError) as ex:
logging.getLogger('PredicateTime').error(
'Problem with parsing data "{0}": {1}'.format(data, ex))
finally:
return dt_object
@staticmethod
def create_datetime_dict(datetime_string):
"""
:type datetime_string: str
:rtype: dict
"""
datetime_regex = (
"^((?P<year>\d{4})\-(?P<month>\d{2})\-(?P<day>\d{2})\s)?"
"(?P<hour>\d{1,2}):(?P<minute>\d{2})(:(?P<second>\d{2}))?")
regex_dict = dict()
match = re.search(datetime_regex, datetime_string)
if match:
regex_dict = dict(year=match.group('year'),
month=match.group('month'),
day=match.group('day'),
hour=match.group('hour'),
minute=match.group('minute'),
second=match.group('second'))
# convert all values to integers
for k, v in regex_dict.iteritems():
if v is not None:
regex_dict[k] = int(v)
logging.getLogger('PredicateTime').debug(
'datetime_dict returning {0}'.format(regex_dict))
return regex_dict
@staticmethod
def parse_range(astr):
"""
https://www.darklaunch.com/2012/11/05/python-parse-range-and-parse-group-range
Return a range list given a string.
As this is for weekdays, only return 0-6
:type astr: str or None
:rtype: list or None
"""
if astr is None:
return None
try:
result = set()
for part in astr.split(','):
x = part.split('-')
result.update(range(int(x[0]), int(x[-1]) + 1))
# only accept 0-6
return [i for i in sorted(result) if 0 <= i <= 6]
except ValueError:
logging.warning('Error parsing day range. Returning [].')
return []
def __repr__(self):
return ('{0}(component={1}, parent={2}, begin="{3}", '
'end="{4}", days={5}, started={6}, operational={7}, met={8})'.
format(self.__class__.__name__, self._comp_name, self._parent,
self.begin, self.end, self.day_range, self.started,
self._operational, self._met))
def __eq__(self, other):
return all([
type(self) == type(other),
self.begin == getattr(other, 'begin', None),
self.end == getattr(other, 'end', None),
self.day_range == getattr(other, 'day_range', None),
self.interval == getattr(other, 'interval', None)
])
def __ne__(self, other):
return any([
type(self) != type(other),
self.begin != getattr(other, 'begin', None),
self.end != getattr(other, 'end', None),
self.day_range != getattr(other, 'day_range', None),
self.interval != getattr(other, 'interval', None)
])
class ZookeeperGoodUntilTime(SimplePredicate):
def __init__(self, comp_name, zkclient, nodepath,
operational=False, parent=None, interval=5):
"""
:type comp_name: str
:type zkclient: kazoo.client.KazooClient
:type nodepath: str
:type operational: bool
:type parent: str or None
:type interval: int or float
"""
SimplePredicate.__init__(self, comp_name, operational=operational, parent=parent)
self.node = nodepath
self.zkclient = zkclient
self.interval = interval
self._start = None
self._stop = None
self._log = logging.getLogger('sent.{0}.pred.gut'.format(comp_name))
self._log.info('Registered {0}'.format(self))
self._operate = ThreadSafeObject(True)
self._thread = Thread(target=self._run_loop, name=str(self))
self._thread.daemon = True
self._started = False
self._datetime_regex = (
"^((?P<year>\d{4})\-(?P<month>\d{2})\-(?P<day>\d{2})\s)?"
"(?P<hour>\d{2}):(?P<minute>\d{2})(:(?P<second>\d{2}))?"
)
@property
def current_time(self):
return datetime.datetime.now().time()
@property
def current_datetime(self):
return datetime.datetime.now()
def start(self):
if self._started is False:
self._log.debug('Starting {0}'.format(self))
self._started = True
self._watch_node()
self._thread.start()
self._block_until_started()
else:
self._log.debug('Already started {0}'.format(self))
def stop(self):
if self._started is True:
self._log.info('Stopping {0}'.format(self))
self._started = False
self._operate.set_value(False)
self._thread.join()
self._log.info('{0} stopped'.format(self))
else:
self._log.debug('Already stopped {0}'.format(self))
def _run_loop(self):
while self._operate == True:
self._process_met()
sleep(self.interval)
self._log.info('Done comparing guts.')
def _process_met(self):
results = []
if self._start is not None:
compare_to_start = self._get_comparison(self._start)
results.append(self._start < compare_to_start)
if self._stop is not None:
compare_to_stop = self._get_comparison(self._stop)
results.append(compare_to_stop < self._stop)
if not results:
results.append(False)
self.set_met(all(results)) # every comparison returned True
def _get_comparison(self, obj):
if isinstance(obj, datetime.datetime):
return self.current_datetime
elif isinstance(obj, datetime.time):
return self.current_time
def _parse_data(self, gut_data):
"""
:type gut_data: dict
"""
start_data = gut_data.get(u'start', None)
self._log.debug('raw start from zk is "{0}"'.format(start_data))
if start_data is not None:
self._start = TimeWindow.get_datetime_object(start_data)
stop_data = gut_data.get(u'stop', None)
self._log.debug('raw stop from zk is "{0}"'.format(stop_data))
if stop_data is not None:
self._stop = TimeWindow.get_datetime_object(stop_data)
if start_data is None and stop_data is None:
self._log.error('Start and Stop time not specified!')
self._log.info('The current time is: {0}. Start time is: {1}. '
'Stop time is: {2}'
.format(self.current_time, self._start, self._stop))
@connected
def _watch_node(self, event=None):
"""
:type event: kazoo.protocol.states.WatchedEvent or None
"""
try:
exists = self.zkclient.exists(self.node, watch=self._watch_node)
if exists:
data, stat = self.zkclient.get(self.node,
watch=self._watch_node)
j = json.loads(data)
self._parse_data(j)
else:
self._log.info('No gut node was found. Watcher is set at {0}'
.format(self.node))
except ValueError as ex:
self._log.error('Invalid GUT JSON object: {0}'.format(ex))
finally:
self._process_met()
def __repr__(self):
return ('{0}(component={1}, parent={2}, start="{3}", stop="{4}", '
'zkpath={5}, started={6}, operational={7}, met={8})'
.format(self.__class__.__name__,
self._comp_name,
self._parent,
self._start,
self._stop,
self.node,
self.started,
self._operational,
self._met))
def __eq__(self, other):
return all([
type(self) == type(other),
self.node == getattr(other, 'node', None)
])
def __ne__(self, other):
return any([
type(self) != type(other),
self.node != getattr(other, 'node', None)
])
class ChildProcess(object):
"""
Wraps a threading.Thread, providing a Queue for communication between
the SentinelDaemon and the ChildProcess.
"""
def __init__(self, config, system, settings):
"""
:type config: xml.etree.ElementTree.Element
:type system: zoom.common.types.PlatformType
:type settings: dict
"""
self._log = logging.getLogger('sent.child')
self._action_queue = UniqueQueue()
self._cancel_flag = ThreadSafeObject(False)
self.name = verify_attribute(config, 'id')
self._application_type = verify_attribute(config, 'type')
self._config = config
self._system = system # Linux or Windows
self._settings = settings
self._process = self._create_process()
def add_work(self, work, immediate=False):
"""
:type work: zoom.agent.task.task.Task
:type immediate: bool
:rtype: bool
"""
return self._action_queue.append_unique(work,
sender=str(self),
first=immediate)
def cancel_current_task(self):
"""
Set the cancel flag that is used in the process client.
"""
# this seems like a hack. There must be a better way of cancelling while
# still allowing the agent to report up/down status
DONT_REMOVE = ('register', 'unregister')
self._log.info('Setting Cancel Flag and clearing queue.')
self._cancel_flag.set_value(True)
for i in list(self._action_queue):
if i.name not in DONT_REMOVE:
self._action_queue.remove(i)
self._log.info('Removing task {0}'.format(i))
def stop(self):
"""
Stops the Process/Thread
"""
try:
self._log.info('Terminating {0} child process'.format(self.name))
self.cancel_current_task()
self.add_work(Task('terminate', block=True), immediate=True)
except Exception as e:
self._log.warning(
'Exception with stopping {0} child process: {1}'.format(
self.name, e))
def join(self):
"""
Block until underlying process completes.
"""
self._process.join()
self._log.info('{0} stopped.'.format(self))
def _create_process(self):
"""
:rtype: threading.Thread
"""
self._log.debug('Starting worker process for %s' % self.name)
if self._application_type == ApplicationType.APPLICATION:
s = Application(self._config, self._settings, self._action_queue,
self._system, self._application_type,
self._cancel_flag)
elif self._application_type == ApplicationType.JOB:
s = Job(self._config, self._settings, self._action_queue,
self._system, self._application_type, self._cancel_flag)
t = Thread(target=s.run, name=self.name)
t.daemon = True
t.start()
return t
def __str__(self):
return 'ChildProcess(name={0}, type={1})'.format(
self.name, self._application_type)
class PredicateProcess(SimplePredicate):
def __init__(self,
comp_name,
proc_client,
interval,
operational=False,
parent=None):
"""
:type comp_name: str
:type proc_client: zoom.agent.client.process_client.ProcessClient
:type interval: int or float
:type operational: bool
:type parent: str or None
"""
SimplePredicate.__init__(self,
comp_name,
operational=operational,
parent=parent)
self._log = logging.getLogger(
'sent.{0}.pred.process'.format(comp_name))
self._proc_client = proc_client
# lock for synchronous decorator
if proc_client:
self.process_client_lock = proc_client.process_client_lock
else:
self.process_client_lock = Lock()
self.interval = interval
self._operate = ThreadSafeObject(True)
self._thread = Thread(target=self._run_loop, name=str(self))
self._thread.daemon = True
self._started = False
def running(self):
"""
With the synchronous decorator, this shares a Lock object with the
ProcessClient. While ProcessClient.start is running, this will not
return.
:rtype: bool
"""
return self._proc_client.running()
def start(self):
if self._started is False:
self._log.debug('Starting {0}'.format(self))
self._started = True
self._thread.start()
self._block_until_started()
else:
self._log.debug('Already started {0}'.format(self))
def stop(self):
if self._started is True:
self._log.info('Stopping {0}'.format(self))
self._started = False
self._operate.set_value(False)
self._thread.join()
self._log.info('{0} stopped'.format(self))
else:
self._log.debug('Already stopped {0}'.format(self))
def _run_loop(self):
cancel_counter = 0
while self._operate == True:
if self._proc_client.cancel_flag == False:
self.set_met(self.running())
cancel_counter = 0
elif cancel_counter > 1:
self._log.info('Waited long enough. Resetting cancel flag.')
self._proc_client.cancel_flag.set_value(False)
cancel_counter = 0
else:
cancel_counter += 1
self._log.info('Cancel Flag detected, skipping status check.')
sleep(self.interval)
self._log.info('Done watching process.')
def __repr__(self):
return ('{0}(component={1}, parent={2}, interval={3}, started={4}, '
'operational={5}, met={6})'.format(
self.__class__.__name__, self._comp_name, self._parent,
self.interval, self.started, self._operational, self._met))
def __eq__(self, other):
return all([
type(self) == type(other),
self.interval == getattr(other, 'interval', None)
])
def __ne__(self, other):
return any([
type(self) != type(other),
self.interval != getattr(other, 'interval', None)
])
class PredicateHealth(SimplePredicate):
def __init__(self,
comp_name,
command,
interval,
system,
operational=False,
parent=None):
"""
:type comp_name: str
:type command: str
:type interval: int or float
:type system: zoom.common.types.PlatformType
:type operational: bool
:type parent: str or None
"""
SimplePredicate.__init__(self,
comp_name,
operational=operational,
parent=parent)
self._log = logging.getLogger('sent.{0}.pred.health'.format(comp_name))
self.interval = interval
self.rawcmd = command
self._runcmd = str()
self._system = system
self._verify()
self._operate = ThreadSafeObject(True)
self._thread = Thread(target=self._run_loop, name=str(self))
self._thread.daemon = True
self._log.info('Registered {0}'.format(self))
self._started = False
def start(self):
if self._started is False:
self._log.debug('Starting {0}'.format(self))
self._started = True
self._thread.start()
self._block_until_started()
else:
self._log.debug('Already started {0}'.format(self))
def stop(self):
if self._started is True:
self._log.info('Stopping {0}'.format(self))
self._started = False
self._operate.set_value(False)
self._thread.join()
self._log.info('{0} stopped'.format(self))
else:
self._log.debug('Already stopped {0}'.format(self))
def _verify(self):
if self._system == PlatformType.LINUX:
self._runcmd = shlex.split(self.rawcmd)
elif self._system == PlatformType.WINDOWS:
self._runcmd = self.rawcmd
else:
self._runcmd = ""
exe = shlex.split(self.rawcmd)[0]
exists = os.path.exists(exe)
if not exists:
searchpath = os.environ['PATH']
for i in searchpath.split(':'):
newpath = os.path.join(i, exe)
if os.path.exists(newpath):
exists = True
break
if not exists:
err = ('Cannot register check "{0}". The path does not exist.'.
format(exe))
self._log.error(err)
raise OSError(err)
def _run(self):
"""
Run the check as a subprocess and return the results as a bool based on
return code. (Non-zero equals failure)
:rtype: bool
"""
p = Popen(self._runcmd, stdout=PIPE, stderr=PIPE)
out, err = p.communicate()
if err:
self._log.error(
'There was some error with the check "{0}"\n{1}'.format(
self.rawcmd, err))
self.set_met(False)
if p.returncode != 0:
self._log.error('Check "{0}" has failed.'.format(self.rawcmd))
self.set_met(False)
else:
self._log.debug('Check "{0}" has succeeded.'.format(self.rawcmd))
self.set_met(True)
def _run_loop(self):
while self._operate == True:
self._run()
sleep(self.interval)
self._log.info('Done running {0}'.format(self))
def __repr__(self):
return ('{0}(component={1}, parent={2}, cmd="{3}", interval={4} '
'started={5}, operational={6}, met={7})'.format(
self.__class__.__name__, self._comp_name, self._parent,
self.rawcmd, self.interval, self.started,
self._operational, self._met))
def __eq__(self, other):
return all([
type(self) == type(other),
self.rawcmd == getattr(other, 'rawcmd', None),
self.interval == getattr(other, 'interval', None)
])
def __ne__(self, other):
return any([
type(self) != type(other),
self.rawcmd != getattr(other, 'rawcmd', None),
self.interval != getattr(other, 'interval', None)
])
class PredicateProcess(SimplePredicate):
def __init__(self, comp_name, settings, proc_client, interval, parent=None):
"""
:type comp_name: str
:type settings: zoom.agent.entities.thread_safe_object.ThreadSafeObject
:type proc_client: zoom.agent.client.process_client.ProcessClient
:type interval: int or float
:type parent: str or None
"""
SimplePredicate.__init__(self, comp_name, settings, parent=parent)
self._log = logging.getLogger('sent.{0}.pred.process'.format(comp_name))
self._proc_client = proc_client
# lock for synchronous decorator
if proc_client:
self.process_client_lock = proc_client.process_client_lock
else:
self.process_client_lock = Lock()
self.interval = interval
self._operate = ThreadSafeObject(True)
self._thread = Thread(target=self._run_loop, name=str(self))
self._thread.daemon = True
self._started = False
def running(self):
"""
With the synchronous decorator, this shares a Lock object with the
ProcessClient. While ProcessClient.start is running, this will not
return.
:rtype: bool
"""
return self._proc_client.running()
def start(self):
if self._started is False:
self._log.debug('Starting {0}'.format(self))
self._started = True
self._thread.start()
else:
self._log.debug('Already started {0}'.format(self))
def stop(self):
if self._started is True:
self._log.info('Stopping {0}'.format(self))
self._started = False
self._operate.set_value(False)
self._thread.join()
self._log.info('{0} stopped'.format(self))
else:
self._log.debug('Already stopped {0}'.format(self))
def _run_loop(self):
while self._operate == True:
self.set_met(self.running())
sleep(self.interval)
self._log.info('Done watching process.')
def __repr__(self):
return ('{0}(component={1}, parent={2}, interval={3}, started={4}, '
'met={5})'
.format(self.__class__.__name__,
self._comp_name,
self._parent,
self.interval,
self.started,
self._met)
)
def __eq__(self, other):
return all([
type(self) == type(other),
self.interval == getattr(other, 'interval', None)
])
def __ne__(self, other):
return any([
type(self) != type(other),
self.interval != getattr(other, 'interval', None)
])
class PredicateHoliday(SimplePredicate):
def __init__(self,
comp_name,
zkclient,
path,
operational=False,
parent=None,
interval=10):
"""
:type comp_name: str
:type zkclient: kazoo.client.KazooClient
:type path: str or None
:type operational: bool
:type parent: str or None
:type interval: int or float
"""
SimplePredicate.__init__(self,
comp_name,
operational=operational,
parent=parent)
self.zkclient = zkclient
self.interval = interval
self.path = path
self._log = logging.getLogger('sent.{0}.holiday'.format(comp_name))
self._log.info('Registered {0}'.format(self))
self._operate = ThreadSafeObject(True)
self._thread = Thread(target=self._run_loop, name=str(self))
self._thread.daemon = True
self._started = False
self._holidays = list()
@property
def date_string(self):
"""
:rtype: str
Example: 20140101
"""
return datetime.date.today().strftime('%Y%m%d')
def start(self):
if self._started is False:
self._log.debug('Starting {0}'.format(self))
self._started = True
self._watch_node()
self._thread.start()
self._block_until_started()
else:
self._log.debug('Already started {0}'.format(self))
def stop(self):
if self._started is True:
self._log.info('Stopping {0}'.format(self))
self._started = False
self._operate.set_value(False)
self._thread.join()
self._log.info('{0} stopped'.format(self))
else:
self._log.debug('Already stopped {0}'.format(self))
def _run_loop(self):
while self._operate == True:
self._process_met()
sleep(self.interval)
self._log.info('Done checking for holiday.')
def _process_met(self):
self.set_met(self.date_string in self._holidays)
@connected
def _watch_node(self, event=None):
"""
:type event: kazoo.protocol.states.WatchedEvent or None
"""
if self.path is None:
self._log.warning('No zookeeper path given. This predicate will'
' nevr be met.')
return
exists = self.zkclient.exists(self.path, watch=self._watch_node)
if exists:
self._holidays = self.zkclient.get_children(self.path,
watch=self._watch_node)
self._log.info('Got holidays {0}'.format(self._holidays))
self._process_met()
else:
self._log.info(
'No gut node was found. Watcher is set at {0}'.format(
self.path))
def __repr__(self):
return ('{0}(component={1}, parent={2}, started={3}, '
'operational={4}, met={5})'.format(self.__class__.__name__,
self._comp_name,
self._parent, self.started,
self._operational,
self._met))
def __eq__(self, other):
return type(self) == type(other)
def __ne__(self, other):
return type(self) != type(other)
class TimeWindow(SimplePredicate):
"""
Predicate for comparing current time to start/stop times.
It will set the 'met' value based on start > current_time > stop.
"""
def __init__(self, comp_name, begin=None, end=None,
weekdays=None, operational=False, parent=None, interval=5):
"""
:type comp_name: str
:type begin: str or None
:type end: str or None
:type weekdays: str or None
:type operational: bool
:type parent: str or None
:type interval: int or float
"""
SimplePredicate.__init__(self, comp_name, operational=operational, parent=parent)
self.begin = self.get_datetime_object(begin)
self.end = self.get_datetime_object(end)
self.day_range = self.parse_range(weekdays)
self.interval = interval
self._log = logging.getLogger('sent.{0}.pred.timewin'.format(comp_name))
self._log.info('Registered {0}'.format(self))
self._operate = ThreadSafeObject(True)
self._thread = Thread(target=self._run_loop, name=str(self))
self._thread.daemon = True
self._started = False
def weekday(self):
"""
:rtype: int
0=Monday, 1=Tuesday, etc.
"""
return datetime.date.today().weekday()
def start(self):
if self._started is False:
self._log.debug('Starting {0}'.format(self))
self._started = True
self._thread.start()
self._block_until_started()
else:
self._log.debug('Already started {0}'.format(self))
def stop(self):
if self._started is True:
self._log.info('Stopping {0}'.format(self))
self._started = False
self._operate.set_value(False)
self._thread.join()
self._log.info('{0} stopped'.format(self))
else:
self._log.debug('Already stopped {0}'.format(self))
def _run_loop(self):
while self._operate == True:
self._process_met()
sleep(self.interval)
self._log.info('Done comparing times.')
def _process_met(self):
results = []
if self.begin is not None:
compare_to_begin = self._get_comparison(self.begin)
results.append(self.begin < compare_to_begin)
if self.end is not None:
compare_to_end = self._get_comparison(self.end)
results.append(compare_to_end < self.end)
if self.day_range is not None:
results.append(self.weekday() in self.day_range)
if not results:
results.append(False)
self.set_met(all(results)) # every comparison returned True
def _get_comparison(self, obj):
if isinstance(obj, datetime.datetime):
return datetime.datetime.now()
elif isinstance(obj, datetime.time):
return datetime.datetime.now().time()
@staticmethod
def get_datetime_object(data):
"""
Create datetime object from string value
:type data: str or None
:rtype: datetime.datetime or datetime.time or None
"""
if data is None:
return
dt_object = None
dt_dict = TimeWindow.create_datetime_dict(data)
try:
# All of year, month and day are not None
if all([dt_dict.get(i, None) is not None
for i in ('year', 'month', 'day')]):
dt_object = datetime.datetime(year=dt_dict['year'],
month=dt_dict['month'],
day=dt_dict['day'],
hour=dt_dict['hour'],
minute=dt_dict['minute'],
microsecond=0)
if dt_dict['second'] is not None:
dt_object = dt_object.replace(second=dt_dict['second'])
# both hour and minute are not None
elif all([dt_dict.get(i, None) is not None
for i in ('hour', 'minute')]):
dt_object = datetime.time(hour=dt_dict['hour'],
minute=dt_dict['minute'],
microsecond=0)
if dt_dict.get('second', None) is not None:
dt_object = dt_object.replace(second=dt_dict['second'])
else:
logging.getLogger('PredicateTime').error(
'data "{0}" did not match regex. This will result in the '
'paramter returning as None. The predicate will never be '
'met for this parameter. '.format(data))
except (ValueError, TypeError) as ex:
logging.getLogger('PredicateTime').error(
'Problem with parsing data "{0}": {1}'.format(data, ex))
finally:
return dt_object
@staticmethod
def create_datetime_dict(datetime_string):
"""
:type datetime_string: str
:rtype: dict
"""
datetime_regex = (
"^((?P<year>\d{4})\-(?P<month>\d{2})\-(?P<day>\d{2})\s)?"
"(?P<hour>\d{1,2}):(?P<minute>\d{2})(:(?P<second>\d{2}))?"
)
regex_dict = dict()
match = re.search(datetime_regex, datetime_string)
if match:
regex_dict = dict(year=match.group('year'),
month=match.group('month'),
day=match.group('day'),
hour=match.group('hour'),
minute=match.group('minute'),
second=match.group('second'))
# convert all values to integers
for k, v in regex_dict.iteritems():
if v is not None:
regex_dict[k] = int(v)
logging.getLogger('PredicateTime').debug(
'datetime_dict returning {0}'.format(regex_dict))
return regex_dict
@staticmethod
def parse_range(astr):
"""
https://www.darklaunch.com/2012/11/05/python-parse-range-and-parse-group-range
Return a range list given a string.
As this is for weekdays, only return 0-6
:type astr: str or None
:rtype: list or None
"""
if astr is None:
return None
try:
result = set()
for part in astr.split(','):
x = part.split('-')
result.update(range(int(x[0]), int(x[-1]) + 1))
# only accept 0-6
return [i for i in sorted(result) if 0 <= i <= 6]
except ValueError:
logging.warning('Error parsing day range. Returning [].')
return []
def __repr__(self):
return ('{0}(component={1}, parent={2}, begin="{3}", '
'end="{4}", days={5}, started={6}, operational={7}, met={8})'
.format(self.__class__.__name__,
self._comp_name,
self._parent,
self.begin,
self.end,
self.day_range,
self.started,
self._operational,
self._met))
def __eq__(self, other):
return all([
type(self) == type(other),
self.begin == getattr(other, 'begin', None),
self.end == getattr(other, 'end', None),
self.day_range == getattr(other, 'day_range', None),
self.interval == getattr(other, 'interval', None)
])
def __ne__(self, other):
return any([
type(self) != type(other),
self.begin != getattr(other, 'begin', None),
self.end != getattr(other, 'end', None),
self.day_range != getattr(other, 'day_range', None),
self.interval != getattr(other, 'interval', None)
])
class APIPredicate(SimplePredicate):
"""
Predicate that polls a url for a specific code.
"""
def __init__(self, comp_name, url, verb='GET', expected_code=200,
interval=5.0, operational=False, parent=None):
"""
:type comp_name: str
:type url: str
:type verb: str
:type expected_code: int
:type interval: int or float
:type operational: bool
:type parent: str or None
"""
SimplePredicate.__init__(self, comp_name, operational=operational, parent=parent)
self._log = logging.getLogger('sent.{0}.pred.api'.format(comp_name))
logging.getLogger('requests.packages.urllib3.connectionpool').setLevel(logging.WARNING)
self.url = url
self.verb = verb
self.expected_code = expected_code
self.interval = interval
self._operate = ThreadSafeObject(True)
self._thread = Thread(target=self._run_loop, name=str(self))
self._thread.daemon = True
self._log.info('Registered {0}'.format(self))
self._started = False
def start(self):
if self._started is False:
self._log.debug('Starting {0}'.format(self))
self._started = True
self._thread.start()
self._block_until_started()
else:
self._log.debug('Already started {0}'.format(self))
def stop(self):
if self._started is True:
self._log.info('Stopping {0}'.format(self))
self._started = False
self._operate.set_value(False)
self._thread.join()
self._log.info('{0} stopped'.format(self))
else:
self._log.debug('Already stopped {0}'.format(self))
def _run(self):
"""
Query the given url, and report whether we get the expected code.
"""
try:
r = requests.request(self.verb, self.url, timeout=2)
self.set_met(r.status_code == self.expected_code)
except requests.ConnectionError:
self._log.debug('URL {0} is not available.'.format(self.url))
self.set_met(False)
except requests.Timeout:
self._log.debug('Timed out to URL {0}.'.format(self.url))
self.set_met(False)
def _run_loop(self):
while self._operate == True:
self._run()
sleep(self.interval)
self._log.info('Done querying {0}'.format(self.url))
def __repr__(self):
return ('{0}(component={1}, parent={2}, url="{3}", verb={4}, '
'interval={5} started={6}, operational={7}, met={8})'
.format(self.__class__.__name__,
self._comp_name,
self._parent,
self.url,
self.verb,
self.interval,
self.started,
self._operational,
self._met))
def __eq__(self, other):
return all([
type(self) == type(other),
self.url == getattr(other, 'url', None),
self.verb == getattr(other, 'verb', None),
self.interval == getattr(other, 'interval', None)
])
def __ne__(self, other):
return any([
type(self) != type(other),
self.url != getattr(other, 'url', None),
self.verb != getattr(other, 'verb', None),
self.interval != getattr(other, 'interval', None)
])
class APIPredicate(SimplePredicate):
"""
Predicate that polls a url for a specific code.
"""
def __init__(self,
comp_name,
url,
verb='GET',
expected_code=200,
interval=5.0,
operational=False,
parent=None):
"""
:type comp_name: str
:type url: str
:type verb: str
:type expected_code: int
:type interval: int or float
:type operational: bool
:type parent: str or None
"""
SimplePredicate.__init__(self,
comp_name,
operational=operational,
parent=parent)
self._log = logging.getLogger('sent.{0}.pred.api'.format(comp_name))
logging.getLogger('requests.packages.urllib3.connectionpool').setLevel(
logging.WARNING)
self.url = url
self.verb = verb
self.expected_code = expected_code
self.interval = interval
self._operate = ThreadSafeObject(True)
self._thread = Thread(target=self._run_loop, name=str(self))
self._thread.daemon = True
self._log.info('Registered {0}'.format(self))
self._started = False
def start(self):
if self._started is False:
self._log.debug('Starting {0}'.format(self))
self._started = True
self._thread.start()
self._block_until_started()
else:
self._log.debug('Already started {0}'.format(self))
def stop(self):
if self._started is True:
self._log.info('Stopping {0}'.format(self))
self._started = False
self._operate.set_value(False)
self._thread.join()
self._log.info('{0} stopped'.format(self))
else:
self._log.debug('Already stopped {0}'.format(self))
def _run(self):
"""
Query the given url, and report whether we get the expected code.
"""
try:
r = requests.request(self.verb, self.url, timeout=2)
self.set_met(r.status_code == self.expected_code)
except requests.ConnectionError:
self._log.debug('URL {0} is not available.'.format(self.url))
self.set_met(False)
except requests.Timeout:
self._log.debug('Timed out to URL {0}.'.format(self.url))
self.set_met(False)
def _run_loop(self):
while self._operate == True:
self._run()
sleep(self.interval)
self._log.info('Done querying {0}'.format(self.url))
def __repr__(self):
return ('{0}(component={1}, parent={2}, url="{3}", verb={4}, '
'interval={5} started={6}, operational={7}, met={8})'.format(
self.__class__.__name__, self._comp_name, self._parent,
self.url, self.verb, self.interval, self.started,
self._operational, self._met))
def __eq__(self, other):
return all([
type(self) == type(other), self.url == getattr(other, 'url', None),
self.verb == getattr(other, 'verb', None),
self.interval == getattr(other, 'interval', None)
])
def __ne__(self, other):
return any([
type(self) != type(other), self.url != getattr(other, 'url', None),
self.verb != getattr(other, 'verb', None),
self.interval != getattr(other, 'interval', None)
])
class ChildProcess(object):
"""
Wraps a threading.Thread, providing a Queue for communication between
the SentinelDaemon and the ChildProcess.
"""
def __init__(self, config, system, settings):
"""
:type config: xml.etree.ElementTree.Element
:type system: zoom.common.types.PlatformType
:type settings: dict
"""
self._log = logging.getLogger("sent.child")
self._action_queue = UniqueQueue()
self._cancel_flag = ThreadSafeObject(False)
self.name = verify_attribute(config, "id")
self._application_type = verify_attribute(config, "type")
self._config = config
self._system = system # Linux or Windows
self._settings = settings
self._process = self._create_process()
def add_work(self, work, immediate=False):
"""
:type work: zoom.agent.task.task.Task
:type immediate: bool
:rtype: bool
"""
return self._action_queue.append_unique(work, sender=str(self), first=immediate)
def cancel_current_task(self):
"""
Set the cancel flag that is used in the process client.
"""
# this seems like a hack. There must be a better way of cancelling while
# still allowing the agent to report up/down status
DONT_REMOVE = ("register", "unregister")
self._log.info("Setting Cancel Flag and clearing queue.")
self._cancel_flag.set_value(True)
for i in list(self._action_queue):
if i.name not in DONT_REMOVE:
self._action_queue.remove(i)
self._log.info("Removing task {0}".format(i))
def stop(self):
"""
Stops the Process/Thread
"""
try:
self._log.info("Terminating {0} child process".format(self.name))
self.cancel_current_task()
self.add_work(Task("terminate", block=True), immediate=True)
except Exception as e:
self._log.warning("Exception with stopping {0} child process: {1}".format(self.name, e))
def join(self):
"""
Block until underlying process completes.
"""
self._process.join()
self._log.info("{0} stopped.".format(self))
def _create_process(self):
"""
:rtype: threading.Thread
"""
self._log.debug("Starting worker process for %s" % self.name)
if self._application_type == ApplicationType.APPLICATION:
s = Application(
self._config,
self._settings,
self._action_queue,
self._system,
self._application_type,
self._cancel_flag,
)
elif self._application_type == ApplicationType.JOB:
s = Job(
self._config,
self._settings,
self._action_queue,
self._system,
self._application_type,
self._cancel_flag,
)
t = Thread(target=s.run, name=self.name)
t.daemon = True
t.start()
return t
def __str__(self):
return "ChildProcess(name={0}, type={1})".format(self.name, self._application_type)
class Application(object):
"""
Service object to represent an deployed service.
"""
def __init__(self, config, settings, queue, system, application_type,
cancel_flag):
"""
:type config: dict (xml)
:type settings: dict
:type queue: zoom.agent.entities.unique_queue.UniqueQueue
:type system: zoom.common.types.PlatformType
:type application_type: zoom.common.types.ApplicationType
:type cancel_flag: zoom.agent.entities.thread_safe_object.ThreadSafeObject
"""
self.config = config
self._settings = settings
self.name = verify_attribute(self.config, 'id', none_allowed=False)
self._log = logging.getLogger('sent.{0}.app'.format(self.name))
# informational attributes
self._host = socket.getfqdn()
self._system = system
self._predicates = list()
self._running = True # used to manually stop the run loop
self._prev_state = None
self._actions = dict() # created in _reset_watches on zk connect
self._env = os.environ.get('EnvironmentToUse', 'Staging')
self._apptype = application_type
self._restart_on_crash = \
verify_attribute(self.config, 'restart_on_crash', none_allowed=True)
self._post_stop_sleep = verify_attribute(self.config, 'post_stop_sleep',
none_allowed=True, cast=int,
default=5)
# tool-like attributes
self.listener_lock = Lock()
self._action_queue = queue
self._mode = ApplicationMode(
ApplicationMode.MANUAL,
callback=self._update_agent_node_with_app_details)
self._state = ThreadSafeObject(
ApplicationState.OK,
callback=self._update_agent_node_with_app_details)
self._start_stop_time = '' # Default to empty string for comparison
self._login_user = '******' # Default to Zoom
self._user_set_in_react = False
self._run_check_mode = False
self._pd_svc_key = verify_attribute(config, 'pagerduty_service',
none_allowed=True)
restartmax = verify_attribute(config, 'restartmax', none_allowed=True,
cast=int, default=3)
self._rl = RestartLogic(
self.name,
restartmax,
count_callback=self._update_agent_node_with_app_details)
self._read_only = False
self._paths = self._init_paths(self.config, settings, application_type)
# clients
self.zkclient = KazooClient(
hosts=get_zk_conn_string(),
timeout=60.0,
handler=SequentialThreadingHandler(),
logger=logging.getLogger('kazoo.app.{0}'.format(self.name)))
self.zkclient.add_listener(self._zk_listener)
self._proc_client = self._init_proc_client(self.config,
application_type,
cancel_flag)
self._actions = self._init_actions(settings)
self._work_manager = self._init_work_manager(self._action_queue)
def app_details(self):
return {'name': self.name,
'host': self._host,
'platform': self._system,
'mode': self._mode.value,
'state': self._state.value,
'start_stop_time': self._start_stop_time,
'login_user': self._login_user,
'read_only': self._read_only,
'restart_count': self._rl.count}
def run(self):
"""
- Start the zookeeper client
- Check for already running instances.
- Start main loop, periodically checking whether the process has failed.
"""
try:
self.zkclient.start()
# make all action objects start processing predicates
self._log.info('Starting to process Actions.')
map(lambda x: x.start(), self._actions.values()) # start actions
started = all([i.started for i in self._actions.values()])
if not started:
self._log.critical('All actions are not started!')
else:
self._log.info('All actions started.'.format(started))
self._check_mode() # get global mode AFTER starting actions
while self._running:
sleep(5)
self.uninitialize()
except Exception as ex:
self._log.critical('There was an exception in the main loop. '
'In a bad state. ({0})'.format(ex))
@catch_exception(NodeExistsError)
@connected
def register(self, **kwargs):
"""
Add entry to the state tree
"""
action_name = kwargs.get('action_name', 'register')
if not self.zkclient.exists(self._paths['zk_state_path']):
if self._action_is_ready(action_name):
self._log.info('Registering %s in state tree.' % self.name)
self.zkclient.create(self._paths['zk_state_path'],
ephemeral=True,
makepath=True)
# resolve any pager duty alarms
self._create_alert_node(AlertActionType.RESOLVE,
AlertReason.RESOLVED)
# reset restart counters, etc
self._proc_client.reset_counters()
self._state.set_value(ApplicationState.STARTED)
else:
self._log.info('Action {0} is not ready. Not registering.'
.format(action_name))
else:
self._log.info('Already registered (node exists).')
return 0
@catch_exception(NoNodeError)
@connected
def unregister(self, **kwargs):
"""Remove entry from state tree"""
action_name = kwargs.get('action_name', 'unregister')
if self._action_is_ready(action_name):
self._log.info('Un-registering %s from state tree.' % self.name)
self.zkclient.delete(self._paths['zk_state_path'])
return 0
@catch_exception(RuntimeError)
def uninitialize(self):
"""
Gracefully stop this Zookeeper session, then free any resentinels
held by the client.
"""
self._log.info('Stopping Zookeeper client')
self._work_manager.stop()
map(lambda x: x.stop(), self._actions.values()) # stop actions
del self._predicates[:] # make sure we delete old predicates
self.zkclient.stop()
self.zkclient.close()
return 0
@time_this
def start(self, **kwargs):
"""
Start actual process
:param kwargs: passed from zoom.handlers.control_agent_handlers
"""
# Restart from UI: ran_stop=True, stay_down=False
# Stop from UI: ran_stop=True, stay_down=True
# Crash: ran_stop=False, stay_down=False
if self._proc_client.restart_logic.ran_stop \
and self._proc_client.restart_logic.stay_down \
and self._apptype == ApplicationType.APPLICATION:
self._log.info('Not starting. App was stopped with Zoom.')
# set to OK just in case we're staggered
self._state.set_value(ApplicationState.OK)
return 0
elif self._proc_client.restart_logic.crashed and \
not self._restart_on_crash:
self._log.info('Not starting. The application has crashed.')
self._state.set_value(ApplicationState.NOTIFY)
return 0
else:
self._log.debug('Start allowed.')
if kwargs.get('reset', True):
self._proc_client.reset_counters()
if kwargs.get('pause', False):
self.ignore()
pd_enabled = kwargs.get('pd_enabled', True)
self._start_stop_time = self._get_current_time()
# set login user if not set in react
if not self._user_set_in_react:
self._login_user = kwargs.get('login_user', 'Zoom')
self._state.set_value(ApplicationState.STARTING)
result = self._proc_client.start()
if self._run_check_mode: # Reset to global mode if restart with dep
self._check_mode()
self._run_check_mode = False
if result == 0 or result == ApplicationStatus.CANCELLED:
self._state.set_value(ApplicationState.STARTED)
else:
self._state.set_value(ApplicationState.ERROR)
if pd_enabled:
self._create_alert_node(AlertActionType.TRIGGER,
AlertReason.FAILEDTOSTART)
else:
self._log.debug('PD is disabled, not sending alert.')
return result
@time_this
def stop(self, **kwargs):
"""
Stop actual process
:param kwargs: Passed from:
zoom.www.handlers.control_agent_handler.ControlAgentHandler,
zoom.agent.action.action.Action
"""
if kwargs.get('reset', True):
self._proc_client.reset_counters()
if kwargs.get('pause', False):
self.ignore()
self._start_stop_time = self._get_current_time()
self._login_user = kwargs.get('login_user', 'Zoom')
self._state.set_value(ApplicationState.STOPPING)
result = self._proc_client.stop(**kwargs)
if result != ApplicationStatus.CANCELLED:
# give everything time to catch up, not sure why anymore...
self._log.info('Sleeping for the configured {0}s after stop.'
.format(self._post_stop_sleep))
sleep(self._post_stop_sleep)
# reset this value back to False
self._user_set_in_react = False
if result == ApplicationStatus.CANCELLED:
self._state.set_value(ApplicationState.STOPPED)
elif result != 0:
self._state.set_value(ApplicationState.ERROR)
else:
self._state.set_value(ApplicationState.STOPPED)
return result
def status(self):
"""
Log out the status of each configured action.
:rtype: str
"""
out = '\n'
out += '#' * 40 + ' STATUS ' + '#' * 40
out += '\n{0}'.format(self)
out += '\n'
for i in self._actions.values():
out += '\n{0}'.format(i.status)
out += '\n'
out += '#' * 40 + ' STATUS ' + '#' * 40
out += '\n'
self._log.info(out)
return out
def restart(self, **kwargs):
"""
:param kwargs: passed from zoom.handlers.control_agent_handlers
"""
# if not self._action_is_ready('restart', allow_undefined=True):
# self._log.info('Restart action not ready.')
# return
self._log.info('Running Restart. Queuing stop, unregister, start.')
self._action_queue.clear()
self._action_queue.append_unique(Task('stop', kwargs=kwargs))
self._action_queue.append_unique(Task('unregister'))
self._action_queue.append_unique(Task('start', kwargs=kwargs))
return 0
def dep_restart(self, **kwargs):
self._run_check_mode = True # only used in self.start()
self._action_queue.append(Task('start_if_ready', kwargs=kwargs))
return 0
def start_if_ready(self, **kwargs):
if self._action_is_ready('start'):
self.start(**kwargs)
# if start action doesn't exist, a.k.a. read only
elif self._actions.get('start', None) is None:
self.start(**kwargs)
else:
self._action_queue.append(Task('react', kwargs=kwargs))
return 0
@time_this
@connected
def ignore(self, **kwargs):
"""
:param kwargs: passed from zoom.handlers.control_agent_handlers
"""
self._mode.set_value(ApplicationMode.MANUAL)
self._log.info('Mode is now "{0}"'.format(self._mode))
return 0
@time_this
@connected
def react(self, **kwargs):
"""
:param kwargs: passed from zoom.handlers.control_agent_handlers
"""
self._mode.set_value(ApplicationMode.AUTO)
self._log.info('Mode is now "{0}"'.format(self._mode))
# when react is called through "restart with dependencies" command
self._user_set_in_react = True
self._login_user = kwargs.get('login_user', 'Zoom')
return 0
@time_this
@connected
def notify(self, **kwargs):
"""
Send notification based on arbitrary predicates
"""
action_name = kwargs.get('action_name', 'notify')
pd_enabled = kwargs.get('pd_enabled', True)
pd_reason = kwargs.get('pd_reason', None)
if pd_reason is None:
pd_reason = AlertReason.CRASHED
if not self._action_is_ready(action_name):
self._log.info('notify action not defined or not ready.')
return 1
self._state.set_value(ApplicationState.NOTIFY)
if pd_enabled:
self._create_alert_node(AlertActionType.TRIGGER, pd_reason)
else:
self._log.debug('PD is disabled, not sending alert.')
return 0
@time_this
@connected
def ensure_running(self, **kwargs):
"""
Essentially a clone of `notify`, but tailored for process monitoring.
"""
# Application failed to start. Already sent PD alert
if self._state == ApplicationState.ERROR:
return 1
action_name = kwargs.get('action_name', 'ensure_running')
pd_enabled = kwargs.get('pd_enabled', True)
pd_reason = kwargs.get('pd_reason', None)
if pd_reason is None:
pd_reason = AlertReason.CRASHED
if not self._action_is_ready(action_name):
self._log.info('notify action not defined or not ready.')
return
if not self._proc_client.restart_logic.ran_stop:
# the application has crashed
self._state.set_value(ApplicationState.NOTIFY)
if pd_enabled:
self._create_alert_node(AlertActionType.TRIGGER, pd_reason)
else:
self._log.debug('PD is disabled, not sending alert.')
else:
self._log.debug("Service shut down gracefully")
return 0
def terminate(self):
"""Terminate child thread/process"""
self._running = False
return 0
def _action_is_ready(self, action_name, allow_undefined=False):
"""
Check if a configured action's predicates are met
:type action_name: str
:type allow_undefined: bool
:rtype: bool
"""
action = self._actions.get(action_name, None)
if allow_undefined:
if action is None:
return True
return action is not None and action.ready
@catch_exception(NoNodeError)
@connected
def _update_agent_node_with_app_details(self, event=None):
"""
Register app data with the agent in the state tree.
:type event: kazoo.protocol.states.WatchedEvent or None
"""
if self._running and \
not self.zkclient.exists(self._paths['zk_state_base']):
self.zkclient.create(self._paths['zk_state_base'], makepath=True)
data, stat = self.zkclient.get(self._paths['zk_state_base'])
try:
agent_apps = json.loads(data)
except ValueError:
agent_apps = dict()
# check for config conflict
other_host = agent_apps.get('host')
if other_host is not None and self._host != other_host:
self._log.error('There is a config conflict with {0}. Updates '
'will no longer be sent until it is resolved.'
.format(other_host))
self._state.set_value(ApplicationState.CONFIG_ERROR,
run_callback=False)
# make sure data is the most recent
if self.app_details() != agent_apps:
self.zkclient.set(self._paths['zk_state_base'],
json.dumps(self.app_details()))
self._log.debug('Registering app data {0}'
.format(self.app_details()))
# set watch
if self._state != ApplicationState.CONFIG_ERROR:
self.zkclient.get(
self._paths['zk_state_base'],
watch=self._update_agent_node_with_app_details)
else:
self._log.error('Shutting down because of config error.')
self.terminate()
def _init_paths(self, config, settings, atype):
"""
:rtype: dict
"""
paths = dict()
paths['zk_state_base'] = verify_attribute(
config,
'registrationpath',
none_allowed=True,
default=self._pathjoin(settings.get('zookeeper', {}).get('state'), atype, self.name)
)
paths['zk_state_path'] = \
self._pathjoin(paths['zk_state_base'], self._host)
paths['zk_config_path'] = \
self._pathjoin(settings.get('zookeeper', {}).get('config'), atype, self.name)
paths['zk_agent_path'] = \
self._pathjoin(settings.get('zookeeper', {}).get('agent_state'), self._host)
return paths
def _init_proc_client(self, config, atype, cancel_flag):
"""Create the process client."""
start_cmd = verify_attribute(config, 'start_cmd', none_allowed=True)
stop_cmd = verify_attribute(config, 'stop_cmd', none_allowed=True)
status_cmd = verify_attribute(config, 'status_cmd', none_allowed=True)
script = verify_attribute(config, 'script', none_allowed=True)
g_names = self._get_graphite_metric_names()
return ProcessClient(name=self.name,
start_cmd=start_cmd,
stop_cmd=stop_cmd,
status_cmd=status_cmd,
script=script,
apptype=atype,
restart_logic=self._rl,
graphite_metric_names=g_names,
cancel_flag=cancel_flag)
def _init_actions(self, settings):
"""
:rtype: dict
"""
action_factory = ActionFactory(component=self,
zkclient=self.zkclient,
proc_client=self._proc_client,
action_queue=self._action_queue,
mode=self._mode,
system=self._system,
pred_list=self._predicates,
app_state=self._state,
settings=settings)
actions = action_factory.create(self.config)
self._determine_read_only(actions)
return actions
def _determine_read_only(self, actions):
start_action = actions.get('start', None)
if start_action is None:
self._read_only = True
elif start_action.disabled is True:
self._read_only = True
else:
self._read_only = False
def _init_work_manager(self, queue):
"""
:rtype: zoom.agent.entities.work_manager.WorkManager
"""
acceptable_work = dict()
# actions have additional logic, so use those if available
for k, v in self._actions.iteritems():
acceptable_work[k] = v.run
# if action is not available, add public methods
for attribute in [a for a in dir(self) if not a.startswith('_')]:
obj = getattr(self, attribute)
if hasattr(obj, '__call__'):
if attribute not in acceptable_work:
acceptable_work[attribute] = obj
else:
self._log.debug('Method {0} already assigned to action.'
.format(attribute))
manager = WorkManager(self.name, queue, acceptable_work)
manager.start()
return manager
@connected
def _check_mode(self, event=None):
"""
Check global run mode for the agents.
:type event: kazoo.protocol.states.WatchedEvent or None
"""
global_path = self._settings.get('zookeeper', {}).get('global_config')
if global_path is None:
self._log.warning('Received no global config path. Zoom will be '
'unable to change the global mode.')
return
modepath = self._pathjoin(global_path, 'mode')
try:
data, stat = self.zkclient.get(modepath, watch=self._check_mode)
j = json.loads(data)
self._log.info('Getting mode from Zookeeper from path: {0}'.
format(modepath))
self._mode.set_value(str(j.get(u'mode', ApplicationMode.MANUAL)))
self._log.info('Setting mode to "{0}"'.format(self._mode))
except NoNodeError:
self._log.info('ZK path {0} does not exist. Assuming mode "manual"'
.format(modepath))
except Exception:
self._log.exception('An uncaught exception has occurred.')
def _pathjoin(self, *args):
"""
Helper function to join paths. Uses string joining if it is a Windows
box.
:rtype: str
"""
if self._system == PlatformType.LINUX:
return os.path.join(*args)
elif self._system == PlatformType.WINDOWS:
return '/'.join(args)
def _get_graphite_metric_names(self):
"""
splits the state path at 'application' and returns the latter index
:rtype: dict
"""
names = {"result": None, "runtime": None, "updown": None}
type_path = self._paths.get('zk_state_base')\
.split(self._settings.get('zookeeper', {}).get('state') + '/', 1)[1]
type_metric = type_path.replace('/', '.')
graphite = self._settings.get('graphite')
if graphite is not None:
result_path = str(graphite.get('result'))
runtime_path = str(graphite.get('runtime'))
updown_path = str(graphite.get('updown'))
names["result"] = result_path.format(type_metric)
names["runtime"] = runtime_path.format(type_metric)
names["updown"] = updown_path.format(type_metric)
return names
def _get_current_time(self):
return datetime.now().strftime("%Y-%m-%d %H:%M:%S")
def _get_alert_details(self, alert_action, reason):
return {
"action": alert_action,
"service_key": self._pd_svc_key,
"incident_key": self._pathjoin('sentinel', self.name, self._host),
"description": ('Sentinel Error: name={0}, host={1}, issue="{2}".'
.format(self.name, self._host, reason)),
"details": ('Sentinel Error: name={0}, host={1}, issue="{2}".\n'
'Review the application log and contact the appropriate'
' development group.'
.format(self.name, self._host, reason))
}
@catch_exception(NoNodeError)
@connected
def _create_alert_node(self, alert_action, reason):
"""
Create Node in ZooKeeper that will result in a PagerDuty alarm
:type alert_action: zoom.common.types.AlertActionType
"""
alert_details = self._get_alert_details(alert_action, reason)
# path example: /foo/sentinel.bar.baz.HOSTFOO
alert = self._settings.get('zookeeper', {}).get('alert')
if alert is None:
self._log.warning('Was given no alert path. This sentinel will be '
'unable to forward alerts to Zoom.')
return
alert_path = self._pathjoin(alert, re.sub('/', '.', alert_details['incident_key']))
if self._env in self._settings.get('pagerduty', {}).get('enabled_environments', []):
self._log.info('Creating alert "{0}" node for env: {1}'
.format(alert_action, self._env))
if self.zkclient.exists(alert_path):
self.zkclient.set(alert_path, value=json.dumps(alert_details))
else:
self.zkclient.create(alert_path, value=json.dumps(alert_details))
else:
self._log.info('Not creating alert "{0}" node for env: {1}'
.format(alert_action, self._env))
self._log.info('Would have created path {0}'.format(alert_path))
@catch_exception(Exception, traceback=True)
@run_only_one('listener_lock')
def _reset_after_connection_loss(self):
"""
Recreates all actions and predicates after connection loss.
Recheck the mode and allowed instances.
"""
if self._running:
self._log.info('Application listener callback triggered')
map(lambda x: x.stop(), self._actions.values()) # stop actions
self._actions.clear()
self._predicates = []
self._actions = self._init_actions(self._settings)
map(lambda x: x.reset(), self._predicates) # reset predicates
map(lambda x: x.start(), self._actions.values()) # start actions
self._check_mode()
self._log.info('Application listener callback complete!')
else:
self._log.info('The daemon has called for termination. '
'Not trying to reset after connection loss.')
def _zk_listener(self, state):
"""
The callback function that runs when the connection state to Zookeeper
changes.
Either passes or immediately spawns a new thread that resets any
watches, etc., so that it can listen to future connection state changes.
"""
try:
self._log.info('Zookeeper Connection went from {0} to {1}'
.format(self._prev_state, state))
if self._prev_state is None and state == KazooState.CONNECTED:
pass
elif self._prev_state == KazooState.LOST and state == KazooState.CONNECTED:
self.zkclient.handler.spawn(self._reset_after_connection_loss)
elif self._prev_state == KazooState.CONNECTED and state == KazooState.SUSPENDED:
pass
elif self._prev_state == KazooState.CONNECTED and state == KazooState.LOST:
pass
elif self._prev_state == KazooState.SUSPENDED and state == KazooState.LOST:
pass
elif self._prev_state == KazooState.SUSPENDED and state == KazooState.CONNECTED:
self.zkclient.handler.spawn(self._reset_after_connection_loss)
elif state == KazooState.CONNECTED:
self.zkclient.handler.spawn(self._reset_after_connection_loss)
else:
self._log.info('Zookeeper Connection in unknown state: {0}'
.format(state))
return
self._prev_state = state
except Exception as ex:
self._log.exception('An uncaught exception has occurred in the '
'listener: {0}'.format(ex))
def __str__(self):
return self.__repr__()
def __repr__(self):
return ("{0}(name={1}, runmode={2})"
.format(self.__class__.__name__, self.name, self._mode))
class WorkManager(object):
def __init__(self, comp_name, queue, work_dict):
"""
:type comp_name: str
:type queue: zoom.agent.entities.unique_queue.UniqueQueue
:type work_dict: dict
"""
self._operate = ThreadSafeObject(True)
self._thread = Thread(target=self._run,
name='work_manager',
args=(self._operate, queue, work_dict))
self._thread.daemon = True
self._log = logging.getLogger('sent.{0}.wm'.format(comp_name))
def start(self):
self._log.info('starting work manager')
self._thread.start()
def stop(self):
self._log.info('Stopping work manager.')
self._operate.set_value(False)
self._thread.join()
self._log.info('Stopped work manager.')
def _run(self, operate, queue, work_dict):
"""
:type operate: zoom.agent.entities.thread_safe_object.ThreadSafeObject
:type queue: zoom.agent.entities.unique_queue.UniqueQueue
:type work_dict: dict
"""
while operate == True:
if queue: # if queue is not empty
self._log.info('Current Task Queue:\n{0}'
.format(pprint.pformat(list(queue))))
task = queue[0] # grab task, but keep it in the queue
if task.func is None:
func_to_run = work_dict.get(task.name, None)
else:
func_to_run = task.func
if func_to_run is not None:
self._log.info('Found work "{0}" in queue.'
.format(task.name))
t = ThreadWithReturn(target=func_to_run, name=task.name,
args=task.args, kwargs=task.kwargs)
t.start()
if task.block:
task.result = t.join()
else:
self._log.warning('Cannot do "{0}", it is not a valid '
'action.'.format(task.name))
try:
queue.remove(task)
except ValueError:
self._log.debug('Item no longer exists in the queue: {0}'
.format(task))
else:
time.sleep(1)
self._log.info('Done listening for work.')
return
class SentinelDaemon(object):
def __init__(self):
"""
Read config and spawn child processes.
"""
self._log = logging.getLogger('sent.daemon')
self._log.info('Creating Sentinel')
self.children = dict()
self._settings = ThreadSafeObject(dict())
self._system = self._get_system()
self._hostname = platform.node().upper() # must be uppercase
self._prev_state = None
self.listener_lock = Lock()
if self._system == PlatformType.LINUX:
self.zkclient = KazooClient(hosts=ZK_CONN_STRING,
handler=SequentialThreadingHandler(),
logger=logging.getLogger('kazoo.daemon'))
elif self._system == PlatformType.WINDOWS:
self.zkclient = KazooClient(hosts=ZK_CONN_STRING,
handler=SequentialThreadingHandler())
self.zkclient.add_listener(self._zk_listener)
# this will run self._reset_after_connection_loss
self.zkclient.start()
self.task_client = None
self.task_client = TaskClient(self.children,
self.zkclient,
self._settings)
self._rest_server = tornado.httpserver.HTTPServer(
RestServer(self.children, self._settings))
signal.signal(signal.SIGINT, self._handle_sigint)
signal.signal(signal.SIGTERM, self._handle_sigint)
self._log.info('Created Sentinel')
def __enter__(self):
logging.info('Starting Sentinel')
self._rest_server.listen('9000')
logging.info('Started Sentinel')
def __exit__(self, exc_type, exc_val, exc_tb):
pass
def stop(self):
"""Terminate all child processes and exit."""
self._log.info('Stopping Sentinel')
self._terminate_children()
self._rest_server.stop()
self._log.info('Stopped Sentinel. Exiting.')
sys.exit(0)
def _handle_sigint(self, sig, frame):
self._log.info('Caught signal %s.' % sig)
self.stop()
@connected
def _get_settings(self, event=None):
"""
Populate self._settings dict.
:type event: kazoo.protocol.states.WatchedEvent or None
"""
data, stat = self.zkclient.get(ZK_AGENT_CONFIG,
watch=self._get_settings)
self._settings.set_value(json.loads(data))
self._log.info('Got settings:\n{0}'
.format(pprint.pformat(self._settings.value)))
@catch_exception(NodeExistsException)
@connected
def _register(self, event=None):
"""
:type event: kazoo.protocol.states.WatchedEvent or None
"""
agent_state_path = self._settings.get('ZK_AGENT_STATE_PATH')
path = '/'.join([agent_state_path, self._hostname])
if not self.zkclient.exists(path, watch=self._register):
self.zkclient.create(path,
value=json.dumps({}),
ephemeral=True)
@connected
def _get_config_and_run(self, event=None):
"""
Grab config from Zookeeper. Spawn ChildProcess instances.
:type event: kazoo.protocol.states.WatchedEvent or None
"""
agent_config_path = self._settings.get('ZK_AGENT_CONFIG_PATH')
config_path = '/'.join([agent_config_path, self._hostname])
try:
if not self.zkclient.exists(config_path,
watch=self._get_config_and_run):
self._log.warning('Node does not exist at: {0}. Creating.'
.format(config_path))
self.zkclient.create(
config_path, value='<?xml version= "1.0"?><Application />')
return
data, stat = self.zkclient.get(config_path)
config = ElementTree.fromstring(data.strip())
self._terminate_children()
self._spawn_children(config)
except ParseError as e:
self._log.error('Incomplete XML config found in path {0}: {1}'
.format(config_path, e))
except ZookeeperError as e:
self._log.error('ZK server returned a non-zero error code: {0}'
.format(e))
except Exception as e:
self._log.exception('There were some Exception: {0}'.format(e))
def _spawn_children(self, config):
"""
Populate the self.children dictionary
:type config: xml.etree.ElementTree.Element
"""
for component in config.iter('Component'):
try:
name = verify_attribute(component, 'id')
self._log.info('Spawning %s' % name)
self.children[name] = {
'config': component,
'process': ChildProcess(component,
self._system,
self._settings)
}
except ValueError as e:
self._log.error('Error with ID in config: {0}'.format(e))
continue
def _terminate_children(self):
"""
Stop all children in the self.children dictionary, and clear it.
"""
self._log.info('Stopping children.')
for child in self.children.values():
process = child['process']
self._log.info('Terminating child -- {0}'.format(process))
process.stop()
# sent stop to all, now wait for all to complete
map(lambda i: i.join(), [x['process'] for x in self.children.values()])
self.children.clear()
@catch_exception(Exception, traceback=True)
@run_only_one('listener_lock')
@connected
def _reset_after_connection_loss(self):
"""
Used for spawning child process and resetting watches ZK connection
changes. This includes the first connection to Zookeeper (on startup).
"""
self._log.info('Daemon listener callback triggered')
self._get_settings()
self._register()
self._get_config_and_run()
if self.task_client is not None:
self.task_client.reset_watches()
self._log.info('Daemon listener callback complete!')
def _zk_listener(self, state):
"""
The callback function that runs when the connection state to Zookeeper
changes.
Either passes or immediately spawns a new thread that resets any
watches, etc., so that it can listen to future connection state changes.
"""
try:
self._log.info('Zookeeper Connection went from {0} to {1}'
.format(self._prev_state, state))
if (self._prev_state == KazooState.LOST
and state == KazooState.CONNECTED):
self.zkclient.handler.spawn(self._reset_after_connection_loss)
elif (self._prev_state == KazooState.CONNECTED
and state == KazooState.SUSPENDED):
pass
elif (self._prev_state == KazooState.CONNECTED
and state == KazooState.LOST):
pass
elif (self._prev_state == KazooState.SUSPENDED
and state == KazooState.LOST):
pass
elif (self._prev_state == KazooState.SUSPENDED
and state == KazooState.CONNECTED):
self.zkclient.handler.spawn(self._reset_after_connection_loss)
elif state == KazooState.CONNECTED:
self.zkclient.handler.spawn(self._reset_after_connection_loss)
else:
self._log.info('Zookeeper Connection in unknown state: {0}'
.format(state))
return
self._prev_state = state
except Exception as e:
self._log.error('Listener excepted out with error: {0}'.format(e))
def _get_system(self):
system_str = platform.platform(terse=True)
if 'Linux' in system_str:
return PlatformType.LINUX
elif 'Windows' in system_str:
return PlatformType.WINDOWS
else:
return PlatformType.UNKNOWN
class PredicateHealth(SimplePredicate):
def __init__(self, comp_name, command, interval, system,
operational=False, parent=None):
"""
:type comp_name: str
:type command: str
:type interval: int or float
:type system: zoom.common.types.PlatformType
:type operational: bool
:type parent: str or None
"""
SimplePredicate.__init__(self, comp_name, operational=operational, parent=parent)
self._log = logging.getLogger('sent.{0}.pred.health'.format(comp_name))
self.interval = interval
self.rawcmd = command
self._runcmd = str()
self._system = system
self._verify()
self._operate = ThreadSafeObject(True)
self._thread = Thread(target=self._run_loop, name=str(self))
self._thread.daemon = True
self._log.info('Registered {0}'.format(self))
self._started = False
def start(self):
if self._started is False:
self._log.debug('Starting {0}'.format(self))
self._started = True
self._thread.start()
self._block_until_started()
else:
self._log.debug('Already started {0}'.format(self))
def stop(self):
if self._started is True:
self._log.info('Stopping {0}'.format(self))
self._started = False
self._operate.set_value(False)
self._thread.join()
self._log.info('{0} stopped'.format(self))
else:
self._log.debug('Already stopped {0}'.format(self))
def _verify(self):
if self._system == PlatformType.LINUX:
self._runcmd = shlex.split(self.rawcmd)
elif self._system == PlatformType.WINDOWS:
self._runcmd = self.rawcmd
else:
self._runcmd = ""
exe = shlex.split(self.rawcmd)[0]
exists = os.path.exists(exe)
if not exists:
searchpath = os.environ['PATH']
for i in searchpath.split(':'):
newpath = os.path.join(i, exe)
if os.path.exists(newpath):
exists = True
break
if not exists:
err = ('Cannot register check "{0}". The path does not exist.'
.format(exe))
self._log.error(err)
raise OSError(err)
def _run(self):
"""
Run the check as a subprocess and return the results as a bool based on
return code. (Non-zero equals failure)
:rtype: bool
"""
p = Popen(self._runcmd, stdout=PIPE, stderr=PIPE)
out, err = p.communicate()
if err:
self._log.error('There was some error with the check "{0}"\n{1}'
.format(self.rawcmd, err))
self.set_met(False)
if p.returncode != 0:
self._log.error('Check "{0}" has failed.'.format(self.rawcmd))
self.set_met(False)
else:
self._log.debug('Check "{0}" has succeeded.'.format(self.rawcmd))
self.set_met(True)
def _run_loop(self):
while self._operate == True:
self._run()
sleep(self.interval)
self._log.info('Done running {0}'.format(self))
def __repr__(self):
return ('{0}(component={1}, parent={2}, cmd="{3}", interval={4} '
'started={5}, operational={6}, met={7})'
.format(self.__class__.__name__,
self._comp_name,
self._parent,
self.rawcmd,
self.interval,
self.started,
self._operational,
self._met))
def __eq__(self, other):
return all([
type(self) == type(other),
self.rawcmd == getattr(other, 'rawcmd', None),
self.interval == getattr(other, 'interval', None)
])
def __ne__(self, other):
return any([
type(self) != type(other),
self.rawcmd != getattr(other, 'rawcmd', None),
self.interval != getattr(other, 'interval', None)
])
class Application(object):
"""
Service object to represent an deployed service.
"""
def __init__(self, config, settings, conn, queue, system, application_type):
"""
:type config: dict (xml)
:type settings: zoom.agent.entities.thread_safe_object.ThreadSafeObject
:type conn: multiprocessing.Connection
:type queue: zoom.agent.entities.unique_queue.UniqueQueue
:type system: zoom.common.types.PlatformType
:type application_type: zoom.common.types.ApplicationType
"""
self.config = config
self._settings = settings
self.name = verify_attribute(self.config, 'id', none_allowed=False)
self._log = logging.getLogger('sent.{0}.app'.format(self.name))
# informational attributes
self._host = platform.node().upper()
self._fqdn = socket.getfqdn()
self._system = system
self._predicates = list()
self._running = True # used to manually stop the run loop
self._prev_state = None
self._actions = dict() # created in _reset_watches on zk connect
self._env = os.environ.get('EnvironmentToUse', 'Staging')
self._apptype = application_type
# tool-like attributes
self.listener_lock = Lock()
self._action_queue = queue
self._mode = ApplicationMode(ApplicationMode.MANUAL)
self._state = ThreadSafeObject(ApplicationState.OK)
self._trigger_time = '' # Default to empty string for comparison
self._login_user = '******' # Default to Zoom
self._run_check_mode = False
self._pd_svc_key = verify_attribute(config, 'pagerduty_service',
none_allowed=True)
self._paths = self._init_paths(self.config, settings, application_type)
# clients
if self._system == PlatformType.LINUX:
self.zkclient = KazooClient(
hosts=ZK_CONN_STRING,
handler=SequentialThreadingHandler(),
logger=logging.getLogger('kazoo.app.{0}'.format(self.name)))
elif self._system == PlatformType.WINDOWS:
self.zkclient = KazooClient(hosts=ZK_CONN_STRING,
handler=SequentialThreadingHandler())
self.zkclient.add_listener(self._zk_listener)
self._proc_client = self._init_proc_client(self.config,
settings,
application_type)
self._actions = self._init_actions(settings)
self._work_manager = self._init_work_manager(self._action_queue, conn)
@property
def app_details(self):
return {'name': self.name,
'host': self._host,
'fqdn': self._fqdn,
'platform': self._system,
'mode': self._mode.value,
'state': self._state.value,
'trigger_time': self._trigger_time,
'login_user': self._login_user}
def run(self):
"""
- Start the zookeeper client
- Check for already running instances.
- Start main loop, periodically checking whether the process has failed.
"""
self.zkclient.start()
# make all action objects start processing predicates
self._log.info('Starting to process Actions.')
map(lambda x: x.start(), self._actions.values()) # start actions
self._check_mode() # get global mode AFTER starting actions
while self._running:
sleep(5)
self.uninitialize()
@catch_exception(NodeExistsError)
@connected
def register(self, **kwargs):
"""
Add entry to the state tree
"""
if not self.zkclient.exists(self._paths['zk_state_path']):
if self._action_is_ready('register'):
self._log.info('Registering %s in state tree.' % self.name)
self.zkclient.create(self._paths['zk_state_path'],
ephemeral=True,
makepath=True)
# resolve any pager duty alarms
self._create_alert_node(AlertActionType.RESOLVE,
AlertReason.RESOLVED)
# reset restart counters, etc
self._proc_client.reset_counters()
self._state.set_value(ApplicationState.OK)
self._update_agent_node_with_app_details()
@catch_exception(NoNodeError)
@connected
def unregister(self, **kwargs):
"""Remove entry from state tree"""
if self._action_is_ready('unregister'):
self._log.info('Un-registering %s from state tree.' % self.name)
self.zkclient.delete(self._paths['zk_state_path'])
@catch_exception(RuntimeError)
def uninitialize(self):
"""
Gracefully stop this Zookeeper session, then free any resentinels
held by the client.
"""
self._log.info('Stopping Zookeeper client')
self._work_manager.stop()
map(lambda x: x.stop(), self._actions.values()) # stop actions
self.zkclient.stop()
self.zkclient.close()
@time_this
def start(self, **kwargs):
"""
Start actual process
:param kwargs: passed from zoom.handlers.control_agent_handlers
"""
# Same check as self.notify() but needed when start action is
# called after process crashes and all predicates are met when on Auto
if not self._proc_client.restart_logic.ran_stop \
and self._apptype == ApplicationType.APPLICATION:
self._log.info('Not starting. App was stopped with Zoom.')
return 0
else:
self._log.debug('Start allowed.')
if kwargs.get('reset', True):
self._proc_client.reset_counters()
if kwargs.get('pause', False):
self.ignore()
pd_enabled = kwargs.get('pd_enabled', True)
self._trigger_time = self._get_current_time()
self._login_user = kwargs.get('login_user', 'Zoom')
self._state.set_value(ApplicationState.STARTING)
self._update_agent_node_with_app_details()
result = self._proc_client.start()
if self._run_check_mode: # Reset to global mode if restart with dep
self._check_mode()
self._run_check_mode = False
if result == 0:
self._state.set_value(ApplicationState.OK)
else:
self._state.set_value(ApplicationState.ERROR)
if pd_enabled:
self._create_alert_node(AlertActionType.TRIGGER,
AlertReason.FAILEDTOSTART)
else:
self._log.debug('PD is disabled, not sending alert.')
self._update_agent_node_with_app_details()
return result
@time_this
def stop(self, **kwargs):
"""
Stop actual process
:param kwargs: passed from zoom.handlers.control_agent_handlers
"""
if kwargs.get('reset', True):
self._proc_client.reset_counters()
if kwargs.get('pause', False):
self.ignore()
self._trigger_time = self._get_current_time()
self._login_user = kwargs.get('login_user', 'Zoom')
self._state.set_value(ApplicationState.STOPPING)
self._update_agent_node_with_app_details()
result = self._proc_client.stop(**kwargs)
if result != 0 and kwargs.get('argument', 'false') == 'false':
self._state.set_value(ApplicationState.ERROR)
else:
self._state.set_value(ApplicationState.OK)
sleep(5) # give everything time to catch up
self._update_agent_node_with_app_details()
return result
def restart(self, **kwargs):
"""
:param kwargs: passed from zoom.handlers.control_agent_handlers
"""
# if not self._action_is_ready('restart', allow_undefined=True):
# self._log.info('Restart action not ready.')
# return
self._log.info('Running Restart. Queuing stop, unregister, start.')
self._action_queue.clear()
self._action_queue.append_unique(Task('stop', kwargs=kwargs))
self._action_queue.append_unique(Task('unregister'))
self._action_queue.append_unique(Task('start', kwargs=kwargs))
def dep_restart(self, **kwargs):
self._run_check_mode = True # only used in self.start()
self._action_queue.append(Task('start_if_ready', pipe=False))
def start_if_ready(self):
if self._action_is_ready('start'):
self.start()
else:
self._action_queue.append(Task('react', pipe=False))
@time_this
@connected
def ignore(self, **kwargs):
"""
:param kwargs: passed from zoom.handlers.control_agent_handlers
"""
self._mode.set_value(ApplicationMode.MANUAL)
self._log.info('Mode is now "{0}"'.format(self._mode))
self._update_agent_node_with_app_details()
return 0
@time_this
@connected
def react(self, **kwargs):
"""
:param kwargs: passed from zoom.handlers.control_agent_handlers
"""
self._mode.set_value(ApplicationMode.AUTO)
self._log.info('Mode is now "{0}"'.format(self._mode))
self._update_agent_node_with_app_details()
return 0
@time_this
@connected
def notify(self, **kwargs):
"""
Send notification to zookeeper that a dependency has gone down.
"""
# Application failed to start. Already sent PD alert
if self._state == ApplicationState.ERROR:
return
pd_enabled = kwargs.get('pd_enabled', True)
if not self._action_is_ready('notify'):
self._log.info('notify action not defined or not ready.')
return
if not self._proc_client.restart_logic.ran_stop:
# the application has crashed
self._state.set_value(ApplicationState.NOTIFY)
self._update_agent_node_with_app_details()
if pd_enabled:
self._create_alert_node(AlertActionType.TRIGGER,
AlertReason.CRASHED)
else:
self._log.debug('PD is disabled, not sending alert.')
else:
self._log.debug("Service shut down gracefully")
def terminate(self):
"""Terminate child thread/process"""
self._running = False
def _action_is_ready(self, action_name, allow_undefined=False):
"""
Check if a configured action's predicates are met
:type action_name: str
:type allow_undefined: bool
:rtype: bool
"""
action = self._actions.get(action_name, None)
if allow_undefined:
if action is None:
return True
return action is not None and action.ready
@connected
def _update_agent_node_with_app_details(self, event=None):
"""
Register app data with the agent in the state tree.
:type event: kazoo.protocol.states.WatchedEvent or None
"""
if self._running and \
not self.zkclient.exists(self._paths['zk_state_base']):
self.zkclient.create(self._paths['zk_state_base'])
data, stat = self.zkclient.get(self._paths['zk_state_base'])
try:
agent_apps = json.loads(data)
except ValueError:
agent_apps = dict()
# check for config conflict
other_host = agent_apps.get('host')
if other_host is not None and self._host != other_host:
self._log.error('There is a config conflict with {0}. Updates '
'will no longer be sent until it is resolved.'
.format(other_host))
self._state.set_value(ApplicationState.CONFIG_ERROR)
# make sure data is the most recent
if self.app_details != agent_apps:
self.zkclient.set(self._paths['zk_state_base'],
json.dumps(self.app_details))
self._log.debug('Registering app data {0}'.format(self.app_details))
# set watch
if self._state != ApplicationState.CONFIG_ERROR:
self.zkclient.get(
self._paths['zk_state_base'],
watch=self._update_agent_node_with_app_details)
else:
self._log.error('Shutting down because of config error.')
self.terminate()
def _init_paths(self, config, settings, atype):
"""
:rtype: dict
"""
paths = dict()
registrationpath = verify_attribute(config, 'registrationpath',
none_allowed=True)
if registrationpath is not None:
paths['zk_state_base'] = registrationpath
else:
paths['zk_state_base'] = \
self._pathjoin(settings.get('ZK_STATE_PATH'), atype, self.name)
paths['zk_state_path'] = \
self._pathjoin(paths['zk_state_base'], self._host)
paths['zk_config_path'] = \
self._pathjoin(settings.get('ZK_CONFIG_PATH'), atype, self.name)
paths['zk_agent_path'] = \
self._pathjoin(settings.get('ZK_AGENT_STATE_PATH'), self._host)
return paths
def _init_proc_client(self, config, settings, atype):
"""Create the process client."""
command = verify_attribute(config, 'command', none_allowed=True)
script = verify_attribute(config, 'script', none_allowed=True)
restartmax = verify_attribute(config, 'restartmax', none_allowed=True,
cast=int)
if restartmax is None:
self._log.info('Restartmax not specified. Assuming 3.')
restartmax = 3
g_names = self._get_graphite_metric_names()
return ProcessClient(name=self.name,
command=command,
script=script,
apptype=atype,
system=self._system,
restart_logic=RestartLogic(restartmax),
graphite_metric_names=g_names,
settings=settings)
def _init_actions(self, settings):
"""
:rtype: dict
"""
action_factory = ActionFactory(component=self,
zkclient=self.zkclient,
proc_client=self._proc_client,
action_queue=self._action_queue,
mode=self._mode,
system=self._system,
pred_list=self._predicates,
settings=settings)
return action_factory.create(self.config)
def _init_work_manager(self, queue, pipe):
"""
:rtype: zoom.agent.entities.work_manager.WorkManager
"""
acceptable_work = dict()
# actions have additional logic, so use those if available
for k, v in self._actions.iteritems():
acceptable_work[k] = v.run
# if action is not available, add the method from Application
for w in self._settings.get('ALLOWED_WORK', []):
if w not in acceptable_work:
if hasattr(self, w):
acceptable_work[w] = self.__getattribute__(w)
else:
self._log.error('Class has no method {0}'.format(w))
else:
self._log.debug('Method {0} already assigned to action.'
.format(w))
manager = WorkManager(self.name, queue, pipe, acceptable_work)
manager.start()
return manager
@connected
def _check_mode(self, event=None):
"""
Check global run mode for the agents.
:type event: kazoo.protocol.states.WatchedEvent or None
"""
modepath = self._pathjoin(self._settings.get('ZK_GLOBAL_PATH'), 'mode')
try:
data, stat = self.zkclient.get(modepath, watch=self._check_mode)
j = json.loads(data)
self._log.info('Getting mode from Zookeeper from path: {0}'.
format(modepath))
self._mode.set_value(str(j.get(u'mode', ApplicationMode.MANUAL)))
self._log.info('Setting mode to "{0}"'.format(self._mode))
self._update_agent_node_with_app_details()
except NoNodeError:
self._log.info('ZK path {0} does not exist. Assuming mode "manual"'
.format(modepath))
except Exception:
self._log.exception('An uncaught exception has occurred.')
def _pathjoin(self, *args):
"""
Helper function to join paths. Uses string joining if it is a Windows
box.
:rtype: str
"""
if self._system == PlatformType.LINUX:
return os.path.join(*args)
elif self._system == PlatformType.WINDOWS:
return '/'.join(args)
def _get_graphite_metric_names(self):
"""
splits the state path at 'application' and returns the latter index
:rtype: dict
"""
type_path = self._paths.get('zk_state_base')\
.split(self._settings.get('ZK_STATE_PATH') + '/', 1)[1]
type_metric = type_path.replace('/', '.')
result_path = self._settings.get('GRAPHITE_RESULT_METRIC')
runtime_path = self._settings.get('GRAPHITE_RUNTIME_METRIC')
return {
"result": result_path.format(type_metric),
"runtime": runtime_path.format(type_metric)
}
def _get_current_time(self):
return datetime.now().strftime("%Y-%m-%d %H:%M:%S")
def _get_alert_details(self, alert_action, reason):
return {
"action": alert_action,
"service_key": self._pd_svc_key,
"incident_key": self._pathjoin('sentinel', self.name, self._host),
"description": ('Sentinel Error: Application {0} {1} on host {2}.'
.format(self.name, reason, self._host)),
"details": ('Sentinel Error: Application {0} {1} on host {2}.\n'
'Review the application log and contact the appropriate'
' development group.'
.format(self.name, reason, self._host))
}
@catch_exception(NoNodeError)
@connected
def _create_alert_node(self, alert_action, reason):
"""
Create Node in ZooKeeper that will result in a PagerDuty alarm
:type alert_action: zoom.common.types.AlertActionType
"""
alert_details = self._get_alert_details(alert_action, reason)
# path example: /foo/sentinel.bar.baz.HOSTFOO
alert_path = self._pathjoin(
self._settings.get('ZK_ALERT_PATH'),
re.sub('/', '.', alert_details['incident_key'])
)
if self._env in self._settings.get('PAGERDUTY_ENABLED_ENVIRONMENTS'):
self._log.info('Creating alert "{0}" node for env: {1}'
.format(alert_action, self._env))
if self.zkclient.exists(alert_path):
self.zkclient.set(alert_path, value=json.dumps(alert_details))
else:
self.zkclient.create(alert_path, value=json.dumps(alert_details))
else:
self._log.info('Not creating alert "{0}" node for env: {1}'
.format(alert_action, self._env))
self._log.info('Would have created path {0}'.format(alert_path))
@catch_exception(Exception, traceback=True)
@run_only_one('listener_lock')
def _reset_after_connection_loss(self):
"""
Recreates all actions and predicates after connection loss.
Recheck the mode and allowed instances.
"""
if self._running:
self._log.info('Application listener callback triggered')
map(lambda x: x.stop(), self._actions.values()) # stop actions
self._actions.clear()
self._predicates = []
self._actions = self._init_actions(self._settings)
map(lambda x: x.reset(), self._predicates) # reset predicates
map(lambda x: x.start(), self._actions.values()) # start actions
self._check_mode()
self._log.info('Application listener callback complete!')
else:
self._log.info('The daemon has called for termination. '
'Not trying to reset after connection loss.')
def _zk_listener(self, state):
"""
The callback function that runs when the connection state to Zookeeper
changes.
Either passes or immediately spawns a new thread that resets any
watches, etc., so that it can listen to future connection state changes.
"""
try:
self._log.info('Zookeeper Connection went from {0} to {1}'
.format(self._prev_state, state))
if self._prev_state is None and state == KazooState.CONNECTED:
pass
elif (self._prev_state == KazooState.LOST
and state == KazooState.CONNECTED):
self.zkclient.handler.spawn(self._reset_after_connection_loss)
elif (self._prev_state == KazooState.CONNECTED
and state == KazooState.SUSPENDED):
pass
elif (self._prev_state == KazooState.CONNECTED
and state == KazooState.LOST):
pass
elif (self._prev_state == KazooState.SUSPENDED
and state == KazooState.LOST):
pass
elif (self._prev_state == KazooState.SUSPENDED
and state == KazooState.CONNECTED):
self.zkclient.handler.spawn(self._reset_after_connection_loss)
elif state == KazooState.CONNECTED:
self.zkclient.handler.spawn(self._reset_after_connection_loss)
else:
self._log.info('Zookeeper Connection in unknown state: {0}'
.format(state))
return
self._prev_state = state
except Exception:
self._log.exception('An uncaught exception has occurred')
def __str__(self):
return self.__repr__()
def __repr__(self):
return ("{0}(name={1}, runmode={2}, actions={3})"
.format(self.__class__.__name__,
self.name,
self._mode,
self._actions.keys())
)
class PredicateWeekend(SimplePredicate):
def __init__(self, comp_name, operational=False, parent=None, interval=10):
"""
:type comp_name: str
:type operational: bool
:type parent: str or None
:type interval: int or float
"""
SimplePredicate.__init__(self,
comp_name,
operational=operational,
parent=parent)
self.interval = interval
self._log = logging.getLogger('sent.{0}.weekend'.format(comp_name))
self._log.info('Registered {0}'.format(self))
self._operate = ThreadSafeObject(True)
self._thread = Thread(target=self._run_loop, name=str(self))
self._thread.daemon = True
self._started = False
@property
def weekday(self):
"""
:rtype: int
0=Sunday, 1=Monday, etc.
"""
return datetime.date.today().weekday()
def start(self):
if self._started is False:
self._log.debug('Starting {0}'.format(self))
self._started = True
self._thread.start()
self._block_until_started()
else:
self._log.debug('Already started {0}'.format(self))
def stop(self):
if self._started is True:
self._log.info('Stopping {0}'.format(self))
self._started = False
self._operate.set_value(False)
self._thread.join()
self._log.info('{0} stopped'.format(self))
else:
self._log.debug('Already stopped {0}'.format(self))
def _run_loop(self):
while self._operate == True:
self._process_met()
sleep(self.interval)
self._log.info('Done checking for weekend.')
def _process_met(self):
self.set_met(self.weekday in [Weekdays.SATURDAY, Weekdays.SUNDAY])
def __repr__(self):
return ('{0}(component={1}, parent={2}, started={3}, '
'operational={4}, met={5})'.format(self.__class__.__name__,
self._comp_name,
self._parent, self.started,
self._operational,
self._met))
def __eq__(self, other):
return type(self) == type(other)
def __ne__(self, other):
return type(self) != type(other)
class ZookeeperGoodUntilTime(SimplePredicate):
def __init__(self, comp_name, settings, zkclient, nodepath, parent=None, interval=5):
"""
:type comp_name: str
:type settings: zoom.agent.entities.thread_safe_object.ThreadSafeObject
:type zkclient: kazoo.client.KazooClient
:type nodepath: str
:type parent: str or None
:type interval: int or float
"""
SimplePredicate.__init__(self, comp_name, settings, parent=parent)
self.node = nodepath
self.zkclient = zkclient
self.interval = interval
self._start = None
self._stop = None
self._log = logging.getLogger('sent.{0}.pred.gut'.format(comp_name))
self._log.info('Registered {0}'.format(self))
self._operate = ThreadSafeObject(True)
self._thread = Thread(target=self._run_loop, name=str(self))
self._thread.daemon = True
self._started = False
self._datetime_regex = (
"^((?P<year>\d{4})\-(?P<month>\d{2})\-(?P<day>\d{2})\s)?"
"(?P<hour>\d{2}):(?P<minute>\d{2})(:(?P<second>\d{2}))?"
)
@property
def current_time(self):
return datetime.datetime.now().time()
@property
def current_datetime(self):
return datetime.datetime.now()
def start(self):
if self._started is False:
self._log.debug('Starting {0}'.format(self))
self._started = True
self._watch_node()
self._thread.start()
else:
self._log.debug('Already started {0}'.format(self))
def stop(self):
if self._started is True:
self._log.info('Stopping {0}'.format(self))
self._started = False
self._operate.set_value(False)
self._thread.join()
self._log.info('{0} stopped'.format(self))
else:
self._log.debug('Already stopped {0}'.format(self))
def _run_loop(self):
while self._operate == True:
self._process_met()
sleep(self.interval)
self._log.info('Done comparing guts.')
def _process_met(self):
results = []
if self._start is not None:
compare_to_start = self._get_comparison(self._start)
results.append(self._start < compare_to_start)
if self._stop is not None:
compare_to_stop = self._get_comparison(self._stop)
results.append(compare_to_stop < self._stop)
if not results:
results.append(False)
self.set_met(all(results)) # every comparison returned True
def _create_dt_dict(self, datetime_string):
"""
:type datetime_string: str
:rtype: dict
"""
regex_dict = dict()
match = re.search(self._datetime_regex, datetime_string)
if match:
regex_dict = dict(year=match.group('year'),
month=match.group('month'),
day=match.group('day'),
hour=match.group('hour'),
minute=match.group('minute'),
second=match.group('second'))
for k, v in regex_dict.iteritems():
if v is not None:
regex_dict[k] = int(v)
self._log.debug('dt_dict returning {0}'.format(regex_dict))
return regex_dict
def _get_comparison(self, obj):
if isinstance(obj, datetime.datetime):
return self.current_datetime
elif isinstance(obj, datetime.time):
return self.current_time
def _get_datetime_object(self, data):
"""
:type data: str
:rtype: datetime.datetime or datetime.time or None
"""
dt_object = None
dt_dict = self._create_dt_dict(data)
try:
# All of year, month and day are not None
if all([dt_dict.get(i, None) is not None
for i in ('year', 'month', 'day')]):
dt_object = datetime.datetime(year=dt_dict['year'],
month=dt_dict['month'],
day=dt_dict['day'],
hour=dt_dict['hour'],
minute=dt_dict['minute'],
microsecond=0)
if dt_dict.get('second', None) is not None:
dt_object.replace(second=dt_dict['second'])
# both hour and minute are not None
elif all([dt_dict.get(i, None) is not None
for i in ('hour', 'minute')]):
dt_object = datetime.time(hour=dt_dict['hour'],
minute=dt_dict['minute'],
microsecond=0)
if dt_dict.get('second', None) is not None:
dt_object.replace(second=dt_dict['second'])
else:
self._log.error('data "{0}" did not match regex'.format(data))
except (ValueError, TypeError) as ex:
self._log.error('Problem with parsing data "{0}": {1}'
.format(data, ex))
finally:
return dt_object
def _parse_data(self, gut_data):
"""
:type gut_data: dict
"""
start_data = gut_data.get(u'start', None)
self._log.debug('raw start from zk is "{0}"'.format(start_data))
if start_data is not None:
self._start = self._get_datetime_object(start_data)
stop_data = gut_data.get(u'stop', None)
self._log.debug('raw stop from zk is "{0}"'.format(stop_data))
if stop_data is not None:
self._stop = self._get_datetime_object(stop_data)
if start_data is None and stop_data is None:
self._log.error('Start and Stop time not specified!')
self._log.info('The current time is: {0}. Start time is: {1}. '
'Stop time is: {2}'
.format(self.current_time, self._start, self._stop))
@connected
def _watch_node(self, event=None):
"""
:type event: kazoo.protocol.states.WatchedEvent or None
"""
try:
exists = self.zkclient.exists(self.node, watch=self._watch_node)
if exists:
data, stat = self.zkclient.get(self.node,
watch=self._watch_node)
j = json.loads(data)
self._parse_data(j)
else:
self._log.info('No gut node was found. Watcher is set at {0}'
.format(self.node))
except ValueError as ex:
self._log.error('Invalid GUT JSON object: {0}'.format(ex))
finally:
self._process_met()
def __repr__(self):
return ('{0}(component={1}, parent={2}, start="{3}", stop="{4}", '
'zkpath={5}, started={6}, met={7})'
.format(self.__class__.__name__,
self._comp_name,
self._parent,
self._start,
self._stop,
self.node,
self.started,
self._met))
def __eq__(self, other):
return all([
type(self) == type(other),
self.node == getattr(other, 'node', None)
])
def __ne__(self, other):
return any([
type(self) != type(other),
self.node != getattr(other, 'node', None)
])
class PredicateHoliday(SimplePredicate):
def __init__(self, comp_name, zkclient, path,
operational=False, parent=None, interval=10):
"""
:type comp_name: str
:type zkclient: kazoo.client.KazooClient
:type path: str or None
:type operational: bool
:type parent: str or None
:type interval: int or float
"""
SimplePredicate.__init__(self, comp_name, operational=operational, parent=parent)
self.zkclient = zkclient
self.interval = interval
self.path = path
self._log = logging.getLogger('sent.{0}.holiday'.format(comp_name))
self._log.info('Registered {0}'.format(self))
self._operate = ThreadSafeObject(True)
self._thread = Thread(target=self._run_loop, name=str(self))
self._thread.daemon = True
self._started = False
self._holidays = list()
@property
def date_string(self):
"""
:rtype: str
Example: 20140101
"""
return datetime.date.today().strftime('%Y%m%d')
def start(self):
if self._started is False:
self._log.debug('Starting {0}'.format(self))
self._started = True
self._watch_node()
self._thread.start()
self._block_until_started()
else:
self._log.debug('Already started {0}'.format(self))
def stop(self):
if self._started is True:
self._log.info('Stopping {0}'.format(self))
self._started = False
self._operate.set_value(False)
self._thread.join()
self._log.info('{0} stopped'.format(self))
else:
self._log.debug('Already stopped {0}'.format(self))
def _run_loop(self):
while self._operate == True:
self._process_met()
sleep(self.interval)
self._log.info('Done checking for holiday.')
def _process_met(self):
self.set_met(self.date_string in self._holidays)
@connected
def _watch_node(self, event=None):
"""
:type event: kazoo.protocol.states.WatchedEvent or None
"""
if self.path is None:
self._log.warning('No zookeeper path given. This predicate will'
' nevr be met.')
return
exists = self.zkclient.exists(self.path, watch=self._watch_node)
if exists:
self._holidays = self.zkclient.get_children(self.path,
watch=self._watch_node)
self._log.info('Got holidays {0}'.format(self._holidays))
self._process_met()
else:
self._log.info('No gut node was found. Watcher is set at {0}'
.format(self.path))
def __repr__(self):
return ('{0}(component={1}, parent={2}, started={3}, '
'operational={4}, met={5})'
.format(self.__class__.__name__,
self._comp_name,
self._parent,
self.started,
self._operational,
self._met))
def __eq__(self, other):
return type(self) == type(other)
def __ne__(self, other):
return type(self) != type(other)
class PredicateWeekend(SimplePredicate):
def __init__(self, comp_name, operational=False, parent=None, interval=10):
"""
:type comp_name: str
:type operational: bool
:type parent: str or None
:type interval: int or float
"""
SimplePredicate.__init__(self, comp_name, operational=operational, parent=parent)
self.interval = interval
self._log = logging.getLogger("sent.{0}.weekend".format(comp_name))
self._log.info("Registered {0}".format(self))
self._operate = ThreadSafeObject(True)
self._thread = Thread(target=self._run_loop, name=str(self))
self._thread.daemon = True
self._started = False
@property
def weekday(self):
"""
:rtype: int
0=Sunday, 1=Monday, etc.
"""
return datetime.date.today().weekday()
def start(self):
if self._started is False:
self._log.debug("Starting {0}".format(self))
self._started = True
self._thread.start()
self._block_until_started()
else:
self._log.debug("Already started {0}".format(self))
def stop(self):
if self._started is True:
self._log.info("Stopping {0}".format(self))
self._started = False
self._operate.set_value(False)
self._thread.join()
self._log.info("{0} stopped".format(self))
else:
self._log.debug("Already stopped {0}".format(self))
def _run_loop(self):
while self._operate == True:
self._process_met()
sleep(self.interval)
self._log.info("Done checking for weekend.")
def _process_met(self):
self.set_met(self.weekday in [Weekdays.SATURDAY, Weekdays.SUNDAY])
def __repr__(self):
return "{0}(component={1}, parent={2}, started={3}, " "operational={4}, met={5})".format(
self.__class__.__name__, self._comp_name, self._parent, self.started, self._operational, self._met
)
def __eq__(self, other):
return type(self) == type(other)
def __ne__(self, other):
return type(self) != type(other)
class Application(object):
"""
Service object to represent an deployed service.
"""
def __init__(self, config, settings, queue, system, application_type,
cancel_flag):
"""
:type config: dict (xml)
:type settings: dict
:type queue: zoom.agent.entities.unique_queue.UniqueQueue
:type system: zoom.common.types.PlatformType
:type application_type: zoom.common.types.ApplicationType
:type cancel_flag: zoom.agent.entities.thread_safe_object.ThreadSafeObject
"""
self.config = config
self._settings = settings
self.name = verify_attribute(self.config, 'id', none_allowed=False)
self._log = logging.getLogger('sent.{0}.app'.format(self.name))
# informational attributes
self._host = socket.getfqdn()
self._system = system
self._predicates = list()
self._running = True # used to manually stop the run loop
self._prev_state = None
self._actions = dict() # created in _reset_watches on zk connect
self._env = os.environ.get('EnvironmentToUse', 'Staging')
self._apptype = application_type
self._restart_on_crash = \
verify_attribute(self.config, 'restart_on_crash', none_allowed=True)
self._post_stop_sleep = verify_attribute(self.config,
'post_stop_sleep',
none_allowed=True,
cast=int,
default=5)
# tool-like attributes
self.listener_lock = Lock()
self._action_queue = queue
self._mode = ApplicationMode(
ApplicationMode.MANUAL,
callback=self._update_agent_node_with_app_details)
self._state = ThreadSafeObject(
ApplicationState.OK,
callback=self._update_agent_node_with_app_details)
self._start_stop_time = '' # Default to empty string for comparison
self._login_user = '******' # Default to Zoom
self._user_set_in_react = False
self._run_check_mode = False
self._pd_svc_key = verify_attribute(config,
'pagerduty_service',
none_allowed=True)
restartmax = verify_attribute(config,
'restartmax',
none_allowed=True,
cast=int,
default=3)
self._rl = RestartLogic(
self.name,
restartmax,
count_callback=self._update_agent_node_with_app_details)
self._read_only = False
self._paths = self._init_paths(self.config, settings, application_type)
# clients
self.zkclient = KazooClient(hosts=get_zk_conn_string(),
timeout=60.0,
handler=SequentialThreadingHandler(),
logger=logging.getLogger(
'kazoo.app.{0}'.format(self.name)))
self.zkclient.add_listener(self._zk_listener)
self._proc_client = self._init_proc_client(self.config,
application_type,
cancel_flag)
self._actions = self._init_actions(settings)
self._work_manager = self._init_work_manager(self._action_queue)
def app_details(self):
return {
'name': self.name,
'host': self._host,
'platform': self._system,
'mode': self._mode.value,
'state': self._state.value,
'start_stop_time': self._start_stop_time,
'login_user': self._login_user,
'read_only': self._read_only,
'restart_count': self._rl.count
}
def run(self):
"""
- Start the zookeeper client
- Check for already running instances.
- Start main loop, periodically checking whether the process has failed.
"""
try:
self.zkclient.start()
# make all action objects start processing predicates
self._log.info('Starting to process Actions.')
map(lambda x: x.start(), self._actions.values()) # start actions
started = all([i.started for i in self._actions.values()])
if not started:
self._log.critical('All actions are not started!')
else:
self._log.info('All actions started.'.format(started))
self._check_mode() # get global mode AFTER starting actions
while self._running:
sleep(5)
self.uninitialize()
except Exception as ex:
self._log.critical('There was an exception in the main loop. '
'In a bad state. ({0})'.format(ex))
@catch_exception(NodeExistsError)
@connected
def register(self, **kwargs):
"""
Add entry to the state tree
"""
action_name = kwargs.get('action_name', 'register')
if not self.zkclient.exists(self._paths['zk_state_path']):
if self._action_is_ready(action_name):
self._log.info('Registering %s in state tree.' % self.name)
self.zkclient.create(self._paths['zk_state_path'],
ephemeral=True,
makepath=True)
# resolve any pager duty alarms
self._create_alert_node(AlertActionType.RESOLVE,
AlertReason.RESOLVED)
# reset restart counters, etc
self._proc_client.reset_counters()
self._state.set_value(ApplicationState.STARTED)
else:
self._log.info(
'Action {0} is not ready. Not registering.'.format(
action_name))
else:
self._log.info('Already registered (node exists).')
return 0
@catch_exception(NoNodeError)
@connected
def unregister(self, **kwargs):
"""Remove entry from state tree"""
action_name = kwargs.get('action_name', 'unregister')
if self._action_is_ready(action_name):
self._log.info('Un-registering %s from state tree.' % self.name)
self.zkclient.delete(self._paths['zk_state_path'])
return 0
@catch_exception(RuntimeError)
def uninitialize(self):
"""
Gracefully stop this Zookeeper session, then free any resentinels
held by the client.
"""
self._log.info('Stopping Zookeeper client')
self._work_manager.stop()
map(lambda x: x.stop(), self._actions.values()) # stop actions
del self._predicates[:] # make sure we delete old predicates
self.zkclient.stop()
self.zkclient.close()
return 0
@time_this
def start(self, **kwargs):
"""
Start actual process
:param kwargs: passed from zoom.handlers.control_agent_handlers
"""
# Restart from UI: ran_stop=True, stay_down=False
# Stop from UI: ran_stop=True, stay_down=True
# Crash: ran_stop=False, stay_down=False
if self._proc_client.restart_logic.ran_stop \
and self._proc_client.restart_logic.stay_down \
and self._apptype == ApplicationType.APPLICATION:
self._log.info('Not starting. App was stopped with Zoom.')
# set to OK just in case we're staggered
self._state.set_value(ApplicationState.OK)
return 0
elif self._proc_client.restart_logic.crashed and \
not self._restart_on_crash:
self._log.info('Not starting. The application has crashed.')
self._state.set_value(ApplicationState.NOTIFY)
return 0
else:
self._log.debug('Start allowed.')
if kwargs.get('reset', True):
self._proc_client.reset_counters()
if kwargs.get('pause', False):
self.ignore()
pd_enabled = kwargs.get('pd_enabled', True)
self._start_stop_time = self._get_current_time()
# set login user if not set in react
if not self._user_set_in_react:
self._login_user = kwargs.get('login_user', 'Zoom')
self._state.set_value(ApplicationState.STARTING)
result = self._proc_client.start()
if self._run_check_mode: # Reset to global mode if restart with dep
self._check_mode()
self._run_check_mode = False
if result == 0 or result == ApplicationStatus.CANCELLED:
self._state.set_value(ApplicationState.STARTED)
else:
self._state.set_value(ApplicationState.ERROR)
if pd_enabled:
self._create_alert_node(AlertActionType.TRIGGER,
AlertReason.FAILEDTOSTART)
else:
self._log.debug('PD is disabled, not sending alert.')
return result
@time_this
def stop(self, **kwargs):
"""
Stop actual process
:param kwargs: Passed from:
zoom.www.handlers.control_agent_handler.ControlAgentHandler,
zoom.agent.action.action.Action
"""
if kwargs.get('reset', True):
self._proc_client.reset_counters()
if kwargs.get('pause', False):
self.ignore()
self._start_stop_time = self._get_current_time()
self._login_user = kwargs.get('login_user', 'Zoom')
self._state.set_value(ApplicationState.STOPPING)
result = self._proc_client.stop(**kwargs)
if result != ApplicationStatus.CANCELLED:
# give everything time to catch up, not sure why anymore...
self._log.info(
'Sleeping for the configured {0}s after stop.'.format(
self._post_stop_sleep))
sleep(self._post_stop_sleep)
# reset this value back to False
self._user_set_in_react = False
if result == ApplicationStatus.CANCELLED:
self._state.set_value(ApplicationState.STOPPED)
elif result != 0:
self._state.set_value(ApplicationState.ERROR)
else:
self._state.set_value(ApplicationState.STOPPED)
return result
def status(self):
"""
Log out the status of each configured action.
:rtype: str
"""
out = '\n'
out += '#' * 40 + ' STATUS ' + '#' * 40
out += '\n{0}'.format(self)
out += '\n'
for i in self._actions.values():
out += '\n{0}'.format(i.status)
out += '\n'
out += '#' * 40 + ' STATUS ' + '#' * 40
out += '\n'
self._log.info(out)
return out
def restart(self, **kwargs):
"""
:param kwargs: passed from zoom.handlers.control_agent_handlers
"""
# if not self._action_is_ready('restart', allow_undefined=True):
# self._log.info('Restart action not ready.')
# return
self._log.info('Running Restart. Queuing stop, unregister, start.')
self._action_queue.clear()
self._action_queue.append_unique(Task('stop', kwargs=kwargs))
self._action_queue.append_unique(Task('unregister'))
self._action_queue.append_unique(Task('start', kwargs=kwargs))
return 0
def dep_restart(self, **kwargs):
self._run_check_mode = True # only used in self.start()
self._action_queue.append(Task('start_if_ready', kwargs=kwargs))
return 0
def start_if_ready(self, **kwargs):
start_action = self._actions.get('start', None)
if start_action is not None and start_action.ready:
start_action.run(**kwargs)
# if start action doesn't exist, a.k.a. read only
elif start_action is None:
self.start(**kwargs)
else:
self._action_queue.append(Task('react', kwargs=kwargs))
return 0
@time_this
@connected
def ignore(self, **kwargs):
"""
:param kwargs: passed from zoom.handlers.control_agent_handlers
"""
self._mode.set_value(ApplicationMode.MANUAL)
self._log.info('Mode is now "{0}"'.format(self._mode))
return 0
@time_this
@connected
def react(self, **kwargs):
"""
:param kwargs: passed from zoom.handlers.control_agent_handlers
"""
self._mode.set_value(ApplicationMode.AUTO)
self._log.info('Mode is now "{0}"'.format(self._mode))
# when react is called through "restart with dependencies" command
self._user_set_in_react = True
self._login_user = kwargs.get('login_user', 'Zoom')
return 0
@time_this
@connected
def notify(self, **kwargs):
"""
Send notification based on arbitrary predicates
"""
action_name = kwargs.get('action_name', 'notify')
pd_enabled = kwargs.get('pd_enabled', True)
pd_reason = kwargs.get('pd_reason', None)
if pd_reason is None:
pd_reason = AlertReason.CRASHED
if not self._action_is_ready(action_name):
self._log.info('notify action not defined or not ready.')
return 1
self._state.set_value(ApplicationState.NOTIFY)
if pd_enabled:
self._create_alert_node(AlertActionType.TRIGGER, pd_reason)
else:
self._log.debug('PD is disabled, not sending alert.')
return 0
@time_this
@connected
def ensure_running(self, **kwargs):
"""
Essentially a clone of `notify`, but tailored for process monitoring.
"""
# Application failed to start. Already sent PD alert
if self._state == ApplicationState.ERROR:
return 1
action_name = kwargs.get('action_name', 'ensure_running')
pd_enabled = kwargs.get('pd_enabled', True)
pd_reason = kwargs.get('pd_reason', None)
if pd_reason is None:
pd_reason = AlertReason.CRASHED
if not self._action_is_ready(action_name):
self._log.info('notify action not defined or not ready.')
return
if not self._proc_client.restart_logic.ran_stop:
# the application has crashed
self._state.set_value(ApplicationState.NOTIFY)
if pd_enabled:
self._create_alert_node(AlertActionType.TRIGGER, pd_reason)
else:
self._log.debug('PD is disabled, not sending alert.')
else:
self._log.debug("Service shut down gracefully")
return 0
def terminate(self):
"""Terminate child thread/process"""
self._running = False
return 0
def _action_is_ready(self, action_name, allow_undefined=False):
"""
Check if a configured action's predicates are met
:type action_name: str
:type allow_undefined: bool
:rtype: bool
"""
action = self._actions.get(action_name, None)
if allow_undefined:
if action is None:
return True
return action is not None and action.ready
@catch_exception(NoNodeError)
@connected
def _update_agent_node_with_app_details(self, event=None):
"""
Register app data with the agent in the state tree.
:type event: kazoo.protocol.states.WatchedEvent or None
"""
if self._running and \
not self.zkclient.exists(self._paths['zk_state_base']):
self.zkclient.create(self._paths['zk_state_base'], makepath=True)
data, stat = self.zkclient.get(self._paths['zk_state_base'])
try:
agent_apps = json.loads(data)
except ValueError:
agent_apps = dict()
# check for config conflict
other_host = agent_apps.get('host')
if other_host is not None and self._host != other_host:
self._log.error(
'There is a config conflict with {0}. Updates '
'will no longer be sent until it is resolved.'.format(
other_host))
self._state.set_value(ApplicationState.CONFIG_ERROR,
run_callback=False)
# make sure data is the most recent
if self.app_details() != agent_apps:
self.zkclient.set(self._paths['zk_state_base'],
json.dumps(self.app_details()))
self._log.debug('Registering app data {0}'.format(
self.app_details()))
# set watch
if self._state != ApplicationState.CONFIG_ERROR:
self.zkclient.get(self._paths['zk_state_base'],
watch=self._update_agent_node_with_app_details)
else:
self._log.error('Shutting down because of config error.')
self.terminate()
def _init_paths(self, config, settings, atype):
"""
:rtype: dict
"""
paths = dict()
paths['zk_state_base'] = verify_attribute(
config,
'registrationpath',
none_allowed=True,
default=self._pathjoin(
settings.get('zookeeper', {}).get('state'), atype, self.name))
paths['zk_state_path'] = \
self._pathjoin(paths['zk_state_base'], self._host)
paths['zk_config_path'] = \
self._pathjoin(settings.get('zookeeper', {}).get('config'), atype, self.name)
paths['zk_agent_path'] = \
self._pathjoin(settings.get('zookeeper', {}).get('agent_state'), self._host)
return paths
def _init_proc_client(self, config, atype, cancel_flag):
"""Create the process client."""
start_cmd = verify_attribute(config, 'start_cmd', none_allowed=True)
stop_cmd = verify_attribute(config, 'stop_cmd', none_allowed=True)
status_cmd = verify_attribute(config, 'status_cmd', none_allowed=True)
script = verify_attribute(config, 'script', none_allowed=True)
g_names = self._get_graphite_metric_names()
return ProcessClient(name=self.name,
start_cmd=start_cmd,
stop_cmd=stop_cmd,
status_cmd=status_cmd,
script=script,
apptype=atype,
restart_logic=self._rl,
graphite_metric_names=g_names,
cancel_flag=cancel_flag)
def _init_actions(self, settings):
"""
:rtype: dict
"""
action_factory = ActionFactory(component=self,
zkclient=self.zkclient,
proc_client=self._proc_client,
action_queue=self._action_queue,
mode=self._mode,
system=self._system,
pred_list=self._predicates,
app_state=self._state,
settings=settings)
actions = action_factory.create(self.config)
self._determine_read_only(actions)
return actions
def _determine_read_only(self, actions):
# Sentinel config may include either start or restart blocks, if either are disabled show as read-only
start_action = actions.get('start', None)
restart_action = actions.get('restart', None)
# Two special cases - both start and restart and neither
if start_action and restart_action:
if start_action.disabled and restart_action.disabled:
self._read_only = True
else:
self._read_only = False
return
elif not start_action and not restart_action:
self._log.warning(
'Sentinel config contains neither start nor restart predicates, assuming readonly'
)
self._read_only = True
return
# At this point either start action or restart action must exist
if not start_action:
if restart_action.disabled:
self._read_only = True
else:
self._read_only = False
elif not restart_action:
if start_action.disabled:
self._read_only = True
else:
self._read_only = False
else:
self._log.warning('Unhandled read-only configuration')
self._read_only = False
def _init_work_manager(self, queue):
"""
:rtype: zoom.agent.entities.work_manager.WorkManager
"""
acceptable_work = dict()
# actions have additional logic, so use those if available
for k, v in self._actions.iteritems():
acceptable_work[k] = v.run
# if action is not available, add public methods
for attribute in [a for a in dir(self) if not a.startswith('_')]:
obj = getattr(self, attribute)
if hasattr(obj, '__call__'):
if attribute not in acceptable_work:
acceptable_work[attribute] = obj
else:
self._log.debug(
'Method {0} already assigned to action.'.format(
attribute))
manager = WorkManager(self.name, queue, acceptable_work)
manager.start()
return manager
@connected
def _check_mode(self, event=None):
"""
Check global run mode for the agents.
:type event: kazoo.protocol.states.WatchedEvent or None
"""
global_path = self._settings.get('zookeeper', {}).get('global_config')
if global_path is None:
self._log.warning('Received no global config path. Zoom will be '
'unable to change the global mode.')
return
modepath = self._pathjoin(global_path, 'mode')
try:
data, stat = self.zkclient.get(modepath, watch=self._check_mode)
j = json.loads(data)
self._log.info(
'Getting mode from Zookeeper from path: {0}'.format(modepath))
self._mode.set_value(str(j.get(u'mode', ApplicationMode.MANUAL)))
self._log.info('Setting mode to "{0}"'.format(self._mode))
except NoNodeError:
self._log.info(
'ZK path {0} does not exist. Assuming mode "manual"'.format(
modepath))
except Exception:
self._log.exception('An uncaught exception has occurred.')
def _pathjoin(self, *args):
"""
Helper function to join paths. Uses string joining if it is a Windows
box.
:rtype: str
"""
if self._system == PlatformType.LINUX:
return os.path.join(*args)
elif self._system == PlatformType.WINDOWS:
return '/'.join(args)
def _get_graphite_metric_names(self):
"""
splits the state path at 'application' and returns the latter index
:rtype: dict
"""
names = {"result": None, "runtime": None, "updown": None}
type_path = self._paths.get('zk_state_base')\
.split(self._settings.get('zookeeper', {}).get('state') + '/', 1)[1]
type_metric = type_path.replace('/', '.')
graphite = self._settings.get('graphite')
if graphite is not None:
result_path = str(graphite.get('result'))
runtime_path = str(graphite.get('runtime'))
updown_path = str(graphite.get('updown'))
names["result"] = result_path.format(type_metric)
names["runtime"] = runtime_path.format(type_metric)
names["updown"] = updown_path.format(type_metric)
return names
def _get_current_time(self):
return datetime.now().strftime("%Y-%m-%d %H:%M:%S")
def _get_alert_details(self, alert_action, reason):
return {
"action":
alert_action,
"service_key":
self._pd_svc_key,
"incident_key":
self._pathjoin('sentinel', self.name, self._host),
"description":
('Sentinel Error: name={0}, host={1}, issue="{2}".'.format(
self.name, self._host, reason)),
"details":
('Sentinel Error: name={0}, host={1}, issue="{2}".\n'
'Review the application log and contact the appropriate'
' development group.'.format(self.name, self._host, reason))
}
@catch_exception(NoNodeError)
@connected
def _create_alert_node(self, alert_action, reason):
"""
Create Node in ZooKeeper that will result in a PagerDuty alarm
:type alert_action: zoom.common.types.AlertActionType
"""
alert_details = self._get_alert_details(alert_action, reason)
# path example: /foo/sentinel.bar.baz.HOSTFOO
alert = self._settings.get('zookeeper', {}).get('alert')
if alert is None:
self._log.warning('Was given no alert path. This sentinel will be '
'unable to forward alerts to Zoom.')
return
alert_path = self._pathjoin(
alert, re.sub('/', '.', alert_details['incident_key']))
if self._env in self._settings.get('pagerduty',
{}).get('enabled_environments', []):
self._log.info('Creating alert "{0}" node for env: {1}'.format(
alert_action, self._env))
if self.zkclient.exists(alert_path):
self.zkclient.set(alert_path, value=json.dumps(alert_details))
else:
self.zkclient.create(alert_path,
value=json.dumps(alert_details))
else:
self._log.info('Not creating alert "{0}" node for env: {1}'.format(
alert_action, self._env))
self._log.info('Would have created path {0}'.format(alert_path))
@catch_exception(Exception, traceback=True)
@run_only_one('listener_lock')
def _reset_after_connection_loss(self):
"""
Recreates all actions and predicates after connection loss.
Recheck the mode and allowed instances.
"""
if self._running:
self._log.info('Application listener callback triggered')
map(lambda x: x.stop(), self._actions.values()) # stop actions
self._actions.clear()
self._predicates = []
self._actions = self._init_actions(self._settings)
map(lambda x: x.reset(), self._predicates) # reset predicates
map(lambda x: x.start(), self._actions.values()) # start actions
self._check_mode()
self._log.info('Application listener callback complete!')
else:
self._log.info('The daemon has called for termination. '
'Not trying to reset after connection loss.')
def _zk_listener(self, state):
"""
The callback function that runs when the connection state to Zookeeper
changes.
Either passes or immediately spawns a new thread that resets any
watches, etc., so that it can listen to future connection state changes.
"""
try:
self._log.info('Zookeeper Connection went from {0} to {1}'.format(
self._prev_state, state))
if self._prev_state is None and state == KazooState.CONNECTED:
pass
elif self._prev_state == KazooState.LOST and state == KazooState.CONNECTED:
self.zkclient.handler.spawn(self._reset_after_connection_loss)
elif self._prev_state == KazooState.CONNECTED and state == KazooState.SUSPENDED:
pass
elif self._prev_state == KazooState.CONNECTED and state == KazooState.LOST:
pass
elif self._prev_state == KazooState.SUSPENDED and state == KazooState.LOST:
pass
elif self._prev_state == KazooState.SUSPENDED and state == KazooState.CONNECTED:
self.zkclient.handler.spawn(self._reset_after_connection_loss)
elif state == KazooState.CONNECTED:
self.zkclient.handler.spawn(self._reset_after_connection_loss)
else:
self._log.info(
'Zookeeper Connection in unknown state: {0}'.format(state))
return
self._prev_state = state
except Exception as ex:
self._log.exception('An uncaught exception has occurred in the '
'listener: {0}'.format(ex))
def __str__(self):
return self.__repr__()
def __repr__(self):
return ("{0}(name={1}, runmode={2})".format(self.__class__.__name__,
self.name, self._mode))