class Spawner(object):
def __init__(self):
self.num_workers = int(Config.get('workers', 'init_count'))
self.secret = os.environ.get('_abaco_secret')
self.queue = os.environ.get('queue', 'default')
self.cmd_ch = CommandChannel(name=self.queue)
self.tot_workers = 0
try:
self.host_id = Config.get('spawner', 'host_id')
except Exception as e:
logger.critical("Spawner not configured with a host_id! Aborting! Exception: {}".format(e))
raise e
def run(self):
while True:
# check resource threshold before subscribing
while True:
if self.overloaded():
logger.critical("METRICS - SPAWNER FOR HOST {} OVERLOADED!!!".format(self.host_id))
# self.update_status to OVERLOADED
time.sleep(5)
else:
break
cmd, msg_obj = self.cmd_ch.get_one()
# directly ack the messages from the command channel; problems generated from starting workers are
# handled downstream; e.g., by setting the actor in an ERROR state; command messages should not be re-queued
msg_obj.ack()
try:
self.process(cmd)
except Exception as e:
logger.error("spawner got an exception trying to process cmd: {}. "
"Exception type: {}. Exception: {}".format(cmd, type(e), e))
def get_tot_workers(self):
logger.debug("top of get_tot_workers")
self.tot_workers = 0
logger.debug('spawner host_id: {}'.format(self.host_id))
for k,v in workers_store.items():
for wid, worker in v.items():
if worker.get('host_id') == self.host_id:
self.tot_workers += 1
logger.debug("returning total workers: {}".format(self.tot_workers))
return self.tot_workers
def overloaded(self):
logger.debug("top of overloaded")
self.get_tot_workers()
logger.info("total workers for this host: {}".format(self.tot_workers))
if self.tot_workers >= MAX_WORKERS:
return True
def stop_workers(self, actor_id, worker_ids):
"""Stop existing workers; used when updating an actor's image."""
logger.debug("Top of stop_workers() for actor: {}.".format(actor_id))
try:
workers_dict = workers_store[actor_id]
except KeyError:
logger.debug("workers_store had no workers for actor: {}".format(actor_id))
workers_dict = {}
# if there are existing workers, we need to close the actor message channel and
# gracefully shutdown the existing worker processes.
if len(workers_dict.items()) > 0:
logger.info("Found {} workers to stop.".format(len(workers_dict.items())))
# first, close the actor msg channel to prevent any new messages from being pulled
# by the old workers.
actor_ch = ActorMsgChannel(actor_id)
actor_ch.close()
logger.info("Actor channel closed for actor: {}".format(actor_id))
# now, send messages to workers for a graceful shutdown:
for _, worker in workers_dict.items():
# don't stop the new workers:
if worker['id'] not in worker_ids:
ch = WorkerChannel(worker_id=worker['id'])
# since this is an update, there are new workers being started, so
# don't delete the actor msg channel:
ch.put('stop-no-delete')
logger.info("Sent 'stop-no-delete' message to worker_id: {}".format(worker['id']))
ch.close()
else:
logger.debug("skipping worker {} as it it not in worker_ids.".format(worker))
else:
logger.info("No workers to stop.")
def process(self, cmd):
"""Main spawner method for processing a command from the CommandChannel."""
logger.info("top of process; cmd: {}".format(cmd))
actor_id = cmd['actor_id']
try:
actor = Actor.from_db(actors_store[actor_id])
except Exception as e:
msg = f"Exception in spawner trying to retrieve actor object from store. Aborting. Exception: {e}"
logger.error(msg)
return
worker_id = cmd['worker_id']
image = cmd['image']
tenant = cmd['tenant']
stop_existing = cmd.get('stop_existing', True)
num_workers = 1
logger.debug("spawner command params: actor_id: {} worker_id: {} image: {} tenant: {}"
"stop_existing: {} num_workers: {}".format(actor_id, worker_id,
image, tenant, stop_existing, num_workers))
# if the worker was sent a delete request before spawner received this message to create the worker,
# the status will be SHUTDOWN_REQUESTED, not REQUESTED. in that case, we simply abort and remove the
# worker from the collection.
try:
logger.debug("spawner checking worker's status for SHUTDOWN_REQUESTED")
worker = Worker.get_worker(actor_id, worker_id)
logger.debug(f"spawner got worker; worker: {worker}")
except Exception as e:
logger.error(f"spawner got exception trying to retrieve worker. "
f"actor_id: {actor_id}; worker_id: {worker_id}; e: {e}")
return
status = worker.get('status')
if not status == REQUESTED:
logger.debug(f"worker was NOT in REQUESTED status. status: {status}")
if status == SHUTDOWN_REQUESTED or status == SHUTTING_DOWN or status == ERROR:
logger.debug(f"worker status was {status}; spawner deleting worker and returning..")
try:
Worker.delete_worker(actor_id, worker_id)
logger.debug("spawner deleted worker because it was SHUTDOWN_REQUESTED.")
return
except Exception as e:
logger.error(f"spawner got exception trying to delete a worker in SHUTDOWN_REQUESTED status."
f"actor_id: {actor_id}; worker_id: {worker_id}; e: {e}")
return
else:
logger.error(f"spawner found worker in unexpected status: {status}. Not processing command and returning.")
return
# worker status was REQUESTED; moving on to SPAWNER_SETUP ----
Worker.update_worker_status(actor_id, worker_id, SPAWNER_SETUP)
logger.debug("spawner has updated worker status to SPAWNER_SETUP; worker_id: {}".format(worker_id))
client_id = None
client_secret = None
client_access_token = None
client_refresh_token = None
api_server = None
client_secret = None
# ---- Oauth client generation for the worker -------
# check if tenant and instance configured for client generation -
try:
generate_clients = Config.get('workers', f'{tenant}_generate_clients').lower()
except:
logger.debug(f"Did not find a {tenant}_generate_clients config. Looking for a global config.")
generate_clients = Config.get('workers', 'generate_clients').lower()
logger.debug(f"final generate_clients: {generate_clients}")
if generate_clients == "true":
logger.debug("client generation was configured to be available; now checking the actor's token attr.")
# updated 1.3.0-- check whether the actor requires a token:
if actor.token:
logger.debug("spawner starting client generation")
client_id, \
client_access_token, \
client_refresh_token, \
api_server, \
client_secret = self.client_generation(actor_id, worker_id, tenant)
else:
logger.debug("actor's token attribute was False. Not generating client.")
ch = SpawnerWorkerChannel(worker_id=worker_id)
logger.debug("spawner attempting to start worker; worker_id: {}".format(worker_id))
try:
worker = self.start_worker(
image,
tenant,
actor_id,
worker_id,
client_id,
client_access_token,
client_refresh_token,
ch,
api_server,
client_secret
)
except Exception as e:
msg = "Spawner got an exception from call to start_worker. Exception:{}".format(e)
logger.error(msg)
self.error_out_actor(actor_id, worker_id, msg)
if client_id:
self.delete_client(tenant, actor_id, worker_id, client_id, client_secret)
return
logger.debug("Returned from start_worker; Created new worker: {}".format(worker))
ch.close()
logger.debug("Client channel closed")
if stop_existing:
logger.info("Stopping existing workers: {}".format(worker_id))
# TODO - update status to stop_requested
self.stop_workers(actor_id, [worker_id])
def client_generation(self, actor_id, worker_id, tenant):
client_ch = ClientsChannel()
try:
client_msg = client_ch.request_client(
tenant=tenant,
actor_id=actor_id,
worker_id=worker_id,
secret=self.secret
)
except Exception as e:
logger.error("Got a ChannelTimeoutException trying to generate a client for "
"actor_id: {}; worker_id: {}; exception: {}".format(actor_id, worker_id, e))
# put worker in an error state and return
self.error_out_actor(actor_id, worker_id, "Abaco was unable to generate an OAuth client for a new "
"worker for this actor. System administrators have been notified.")
client_ch.close()
Worker.update_worker_status(actor_id, worker_id, ERROR)
logger.critical("Client generation FAILED.")
raise e
client_ch.close()
if client_msg.get('status') == 'error':
logger.error("Error generating client: {}".format(client_msg.get('message')))
self.error_out_actor(actor_id, worker_id, "Abaco was unable to generate an OAuth client for a new "
"worker for this actor. System administrators have been notified.")
Worker.update_worker_status(actor_id, worker_id, ERROR)
raise SpawnerException("Error generating client") #TODO - clean up error message
# else, client was generated successfully:
else:
logger.info("Got a client: {}, {}, {}".format(client_msg['client_id'],
client_msg['access_token'],
client_msg['refresh_token']))
return client_msg['client_id'], \
client_msg['access_token'], \
client_msg['refresh_token'], \
client_msg['api_server'], \
client_msg['client_secret']
def delete_client(self, tenant, actor_id, worker_id, client_id, secret):
clients_ch = ClientsChannel()
msg = clients_ch.request_delete_client(tenant=tenant,
actor_id=actor_id,
worker_id=worker_id,
client_id=client_id,
secret=secret)
if msg['status'] == 'ok':
logger.info("Client delete request completed successfully for "
"worker_id: {}, client_id: {}.".format(worker_id, client_id))
else:
logger.error("Error deleting client for "
"worker_id: {}, client_id: {}. Message: {}".format(worker_id, msg['message'], client_id, msg))
clients_ch.close()
def start_worker(self,
image,
tenant,
actor_id,
worker_id,
client_id,
client_access_token,
client_refresh_token,
ch,
api_server,
client_secret):
# start an actor executor container and wait for a confirmation that image was pulled.
attempts = 0
# worker = get_worker(worker_id)
# worker['status'] = PULLING_IMAGE
Worker.update_worker_status(actor_id, worker_id, PULLING_IMAGE)
try:
logger.debug("Worker pulling image {}...".format(image))
pull_image(image)
except DockerError as e:
# return a message to the spawner that there was an error pulling image and abort
# this is not necessarily an error state: the user simply could have provided an
# image name that does not exist in the registry. This is the first time we would
# find that out.
logger.info("worker got a DockerError trying to pull image. Error: {}.".format(e))
raise e
logger.info("Image {} pulled successfully.".format(image))
# Done pulling image
# Run Worker Container
while True:
try:
Worker.update_worker_status(actor_id, worker_id, CREATING_CONTAINER)
logger.debug('spawner creating worker container')
worker_dict = run_worker(
image,
actor_id,
worker_id,
client_id,
client_access_token,
client_refresh_token,
tenant,
api_server,
client_secret
)
logger.debug(f'finished run worker; worker dict: {worker_dict}')
except DockerError as e:
logger.error("Spawner got a docker exception from run_worker; Exception: {}".format(e))
if 'read timeout' in e.message:
logger.info("Exception was a read timeout; trying run_worker again..")
time.sleep(5)
attempts = attempts + 1
if attempts > 20:
msg = "Spawner continued to get DockerError for 20 attempts. Exception: {}".format(e)
logger.critical(msg)
# todo - should we be calling kill_worker here? (it is called in the exception block of the else below)
raise SpawnerException(msg)
continue
else:
logger.info("Exception was NOT a read timeout; quiting on this worker.")
# delete this worker from the workers store:
try:
self.kill_worker(actor_id, worker_id)
except WorkerException as e:
logger.info("Got WorkerException from delete_worker(). "
"worker_id: {}"
"Exception: {}".format(worker_id, e))
raise SpawnerException(message="Unable to start worker; error: {}".format(e))
break
logger.debug('finished loop')
worker_dict['ch_name'] = WorkerChannel.get_name(worker_id)
# if the actor is not already in READY status, set actor status to READY before worker status has been
# set to READY.
# it is possible the actor status is already READY because this request is the autoscaler starting a new worker
# for an existing actor.
actor = Actor.from_db(actors_store[actor_id])
if not actor.status == READY:
try:
Actor.set_status(actor_id, READY, status_message=" ")
except KeyError:
# it is possible the actor was already deleted during worker start up; if
# so, the worker should have a stop message waiting for it. starting subscribe
# as usual should allow this process to work as expected.
pass
# finalize worker with READY status
worker = Worker(tenant=tenant, **worker_dict)
logger.info("calling add_worker for worker: {}.".format(worker))
Worker.add_worker(actor_id, worker)
ch.put('READY') # step 4
logger.info('sent message through channel')
def error_out_actor(self, actor_id, worker_id, message):
"""In case of an error, put the actor in error state and kill all workers"""
logger.debug("top of error_out_actor for worker: {}_{}".format(actor_id, worker_id))
Actor.set_status(actor_id, ERROR, status_message=message)
# first we try to stop workers using the "graceful" approach -
try:
self.stop_workers(actor_id, worker_ids=[])
logger.info("Spawner just stopped worker {}_{} in error_out_actor".format(actor_id, worker_id))
return
except Exception as e:
logger.error("spawner got exception trying to run stop_workers. Exception: {}".format(e))
try:
self.kill_worker(actor_id, worker_id)
logger.info("Spawner just killed worker {}_{} in error_out_actor".format(actor_id, worker_id))
except DockerError as e:
logger.info("Received DockerError trying to kill worker: {}. Exception: {}".format(worker_id, e))
logger.info("Spawner will continue on since this is exception processing.")
def kill_worker(self, actor_id, worker_id):
try:
Worker.delete_worker(actor_id, worker_id)
except WorkerException as e:
logger.info("Got WorkerException from delete_worker(). "
"worker_id: {}"
"Exception: {}".format(worker_id, e))
except Exception as e:
logger.error("Got an unexpected exception from delete_worker(). "
"worker_id: {}"
"Exception: {}".format(worker_id, e))
class Spawner(object):
def __init__(self):
self.num_workers = int(Config.get('workers', 'init_count'))
self.secret = os.environ.get('_abaco_secret')
self.cmd_ch = CommandChannel()
self.tot_workers = 0
try:
self.host_id = Config.get('spawner', 'host_id')
except Exception as e:
logger.critical("Spawner not configured with a host_id! Aborting! Exception: {}".format(e))
raise e
def run(self):
while True:
# check resource threshold before subscribing
while True:
if self.overloaded():
logger.critical("METRICS - SPAWNER FOR HOST {} OVERLOADED!!!".format(self.host_id))
# self.update_status to OVERLOADED
time.sleep(5)
else:
break
cmd, msg_obj = self.cmd_ch.get_one()
# directly ack the messages from the command channel; problems generated from starting workers are
# handled downstream; e.g., by setting the actor in an ERROR state; command messages should not be re-queued
msg_obj.ack()
self.process(cmd)
def get_tot_workers(self):
logger.debug("top of get_tot_workers")
self.tot_workers = 0
logger.debug('spawner host_id: {}'.format(self.host_id))
for k,v in workers_store.items():
for wid, worker in v.items():
if worker.get('host_id') == self.host_id:
self.tot_workers += 1
logger.debug("returning total workers: {}".format(self.tot_workers))
return self.tot_workers
def overloaded(self):
logger.debug("top of overloaded")
self.get_tot_workers()
logger.info("total workers for this host: {}".format(self.tot_workers))
if self.tot_workers >= MAX_WORKERS:
return True
def stop_workers(self, actor_id, worker_ids):
"""Stop existing workers; used when updating an actor's image."""
logger.debug("Top of stop_workers() for actor: {}.".format(actor_id))
try:
workers_dict = workers_store[actor_id]
except KeyError:
logger.debug("workers_store had no workers for actor: {}".format(actor_id))
workers_dict = {}
# if there are existing workers, we need to close the actor message channel and
# gracefully shutdown the existing worker processes.
if len(workers_dict.items()) > 0:
logger.info("Found {} workers to stop.".format(len(workers_dict.items())))
# first, close the actor msg channel to prevent any new messages from being pulled
# by the old workers.
actor_ch = ActorMsgChannel(actor_id)
actor_ch.close()
logger.info("Actor channel closed for actor: {}".format(actor_id))
# now, send messages to workers for a graceful shutdown:
for _, worker in workers_dict.items():
# don't stop the new workers:
if worker['id'] not in worker_ids:
ch = WorkerChannel(worker_id=worker['id'])
# since this is an update, there are new workers being started, so
# don't delete the actor msg channel:
ch.put('stop-no-delete')
logger.info("Sent 'stop-no-delete' message to worker_id: {}".format(worker['id']))
ch.close()
else:
logger.info("No workers to stop.")
def process(self, cmd):
"""Main spawner method for processing a command from the CommandChannel."""
logger.info("Spawner processing new command:{}".format(cmd))
actor_id = cmd['actor_id']
worker_ids = cmd['worker_ids']
image = cmd['image']
tenant = cmd['tenant']
stop_existing = cmd.get('stop_existing', True)
num_workers = cmd.get('num', self.num_workers)
logger.info("command params: actor_id: {} worker_ids: {} image: {} stop_existing: {} mum_workers: {}".format(
actor_id, worker_ids, image, tenant, stop_existing, num_workers))
try:
new_channels, anon_channels, new_workers = self.start_workers(actor_id,
worker_ids,
image,
tenant,
num_workers)
except SpawnerException as e:
# for now, start_workers will do clean up for a SpawnerException, so we just need
# to return back to the run loop.
logger.info("Spawner returning to main run loop.")
return
logger.info("Created new workers: {}".format(new_workers))
# stop any existing workers:
if stop_existing:
logger.info("Stopping existing workers: {}".format(worker_ids))
self.stop_workers(actor_id, worker_ids)
# add workers to store first so that the records will be there when the workers go
# to update their status
if not stop_existing:
# if we're not stopping the existing workers, we need to add each worker to the
# actor's collection.
for _, worker in new_workers.items():
logger.info("calling add_worker for worker: {}.".format(worker))
Worker.add_worker(actor_id, worker)
else:
# since we're stopping the existing workers, the actor's collection should just
# be equal to the new_workers.
workers_store[actor_id] = new_workers
logger.info("workers_store set to new_workers: {}.".format(new_workers))
# Tell new worker to subscribe to the actor channel.
# If abaco is configured to generate clients for the workers, generate them now
# and send new workers their clients.
generate_clients = Config.get('workers', 'generate_clients').lower()
logger.info("Sending messages to new workers over anonymous channels to subscribe to inbox.")
for idx, channel in enumerate(anon_channels):
if generate_clients == 'true':
worker_id = new_workers[list(new_workers)[idx]]['id']
logger.info("Getting client for worker number {}, id: {}".format(idx, worker_id))
client_ch = ClientsChannel()
try:
client_msg = client_ch.request_client(tenant=tenant,
actor_id=actor_id,
# new_workers is a dictionary of dictionaries; list(d) creates a
# list of keys for a dictionary d. hence, the idx^th entry
# of list(ner_workers) should be the key.
worker_id=worker_id,
secret=self.secret)
except ChannelTimeoutException as e:
logger.error("Got a ChannelTimeoutException trying to generate a client for "
"actor_id: {}; worker_id: {}; exception: {}".format(actor_id, worker_id, e))
# put actor in an error state and return
self.error_out_actor(actor_id, worker_id, "Abaco was unable to generate an OAuth client for a new "
"worker for this actor. System administrators have been notified.")
client_ch.close()
return
client_ch.close()
# we need to ignore errors when generating clients because it's possible it is not set up for a specific
# tenant. we log it instead.
if client_msg.get('status') == 'error':
logger.error("Error generating client: {}".format(client_msg.get('message')))
channel.put({'status': 'ok',
'actor_id': actor_id,
'tenant': tenant,
'client': 'no'})
logger.debug("Sent OK message over anonymous worker channel.")
# else, client was generated successfully:
else:
logger.info("Got a client: {}, {}, {}".format(client_msg['client_id'],
client_msg['access_token'],
client_msg['refresh_token']))
channel.put({'status': 'ok',
'actor_id': actor_id,
'tenant': tenant,
'client': 'yes',
'client_id': client_msg['client_id'],
'client_secret': client_msg['client_secret'],
'access_token': client_msg['access_token'],
'refresh_token': client_msg['refresh_token'],
'api_server': client_msg['api_server'],
})
logger.debug("Sent OK message AND client over anonymous worker channel.")
else:
logger.info("Not generating clients. Config value was: {}".format(generate_clients))
channel.put({'status': 'ok',
'actor_id': actor_id,
'tenant': tenant,
'client': 'no'})
logger.debug("Sent OK message over anonymous worker channel.")
# @TODO -
# delete the anonymous channel from this thread but sleep first to avoid the race condition.
time.sleep(1.5)
channel.delete()
# due to the race condition deleting channels (potentially before all workers have received all messages)
# we put a sleep here.
time.sleep(1)
for ch in new_channels:
try:
# the new_channels are the spawnerworker channels so they can be deleted.
ch.delete()
except Exception as e:
logger.error("Got exception trying to delete spawnerworker channel: {}".format(e))
logger.info("Done processing command.")
def start_workers(self, actor_id, worker_ids, image, tenant, num_workers):
logger.info("starting {} workers. actor_id: {} image: {}".format(str(self.num_workers), actor_id, image))
channels = []
anon_channels = []
workers = {}
try:
for i in range(num_workers):
worker_id = worker_ids[i]
logger.info("starting worker {} with id: {}".format(i, worker_id))
ch, anon_ch, worker = self.start_worker(image, tenant, actor_id, worker_id)
logger.debug("channel for worker {} is: {}".format(str(i), ch.name))
channels.append(ch)
anon_channels.append(anon_ch)
workers[worker_id] = worker
except SpawnerException as e:
logger.info("Caught SpawnerException:{}".format(str(e)))
# in case of an error, put the actor in error state and kill all workers
self.error_out_actor(actor_id, worker_id, e.message)
raise SpawnerException(message=e.message)
return channels, anon_channels, workers
def start_worker(self, image, tenant, actor_id, worker_id):
ch = SpawnerWorkerChannel(worker_id=worker_id)
# start an actor executor container and wait for a confirmation that image was pulled.
attempts = 0
while True:
try:
worker_dict = run_worker(image, actor_id, worker_id)
except DockerError as e:
logger.error("Spawner got a docker exception from run_worker; Exception: {}".format(e))
if 'read timeout' in e.message:
logger.info("Exception was a read timeout; trying run_worker again..")
time.sleep(5)
attempts = attempts + 1
if attempts > 20:
msg = "Spawner continued to get DockerError for 20 attempts. Exception: {}".format(e)
logger.critical(msg)
raise SpawnerException(msg)
continue
else:
logger.info("Exception was NOT a read timeout; quiting on this worker.")
# delete this worker from the workers store:
try:
self.kill_worker(actor_id, worker_id)
except WorkerException as e:
logger.info("Got WorkerException from delete_worker(). "
"worker_id: {}"
"Exception: {}".format(worker_id, e))
raise SpawnerException(message="Unable to start worker; error: {}".format(e))
break
worker_dict['ch_name'] = WorkerChannel.get_name(worker_id)
worker = Worker(tenant=tenant, **worker_dict)
logger.info("worker started successfully, waiting on ack that image was pulled...")
result = ch.get()
logger.debug("Got response back from worker. Response: {}".format(result))
if result.get('status') == 'error':
# there was a problem pulling the image; put the actor in an error state:
msg = "Got an error back from the worker. Message: {}",format(result)
logger.info(msg)
if 'msg' in result:
raise SpawnerException(message=result['msg'])
else:
logger.error("Spawner received invalid message from worker. 'msg' field missing. Message: {}".format(result))
raise SpawnerException(message="Internal error starting worker process.")
elif result['value']['status'] == 'ok':
logger.debug("received ack from worker.")
return ch, result['reply_to'], worker
else:
msg = "Got an error status from worker: {}. Raising an exception.".format(str(result))
logger.error("Spawner received an invalid message from worker. Message: ".format(result))
raise SpawnerException(msg)
def error_out_actor(self, actor_id, worker_id, message):
"""In case of an error, put the actor in error state and kill all workers"""
Actor.set_status(actor_id, ERROR, status_message=message)
try:
self.kill_worker(actor_id, worker_id)
except DockerError as e:
logger.info("Received DockerError trying to kill worker: {}. Exception: {}".format(worker_id, e))
logger.info("Spawner will continue on since this is exception processing.")
def kill_worker(self, actor_id, worker_id):
try:
Worker.delete_worker(actor_id, worker_id)
except WorkerException as e:
logger.info("Got WorkerException from delete_worker(). "
"worker_id: {}"
"Exception: {}".format(worker_id, e))
except Exception as e:
logger.error("Got an unexpected exception from delete_worker(). "
"worker_id: {}"
"Exception: {}".format(worker_id, e))
