# Copyright (C) 2015 The Software Heritage developers # See the AUTHORS file at the top-level directory of this distribution # License: GNU General Public License version 3, or any later version # See top-level LICENSE file for more information import itertools import importlib import logging import os import urllib.parse from celery import Celery from celery.signals import setup_logging, celeryd_after_setup from celery.utils.log import ColorFormatter from celery.worker.control import Panel from kombu import Exchange, Queue from kombu.five import monotonic as _monotonic import requests from swh.scheduler.task import Task from swh.core.config import load_named_config from swh.core.logger import JournalHandler DEFAULT_CONFIG_NAME = 'worker' CONFIG_NAME_ENVVAR = 'SWH_WORKER_INSTANCE' CONFIG_NAME_TEMPLATE = 'worker/%s' DEFAULT_CONFIG = { 'task_broker': ('str', 'amqp://guest@localhost//'), 'task_modules': ('list[str]', []), 'task_queues': ('list[str]', []), 'task_soft_time_limit': ('int', 0), } @setup_logging.connect def setup_log_handler(loglevel=None, logfile=None, format=None, colorize=None, **kwargs): """Setup logging according to Software Heritage preferences. We use the command-line loglevel for tasks only, as we never really care about the debug messages from celery. """ if loglevel is None: loglevel = logging.DEBUG if isinstance(loglevel, str): loglevel = logging._nameToLevel[loglevel] formatter = logging.Formatter(format) root_logger = logging.getLogger('') root_logger.setLevel(logging.INFO) if loglevel == logging.DEBUG: color_formatter = ColorFormatter(format) if colorize else formatter console = logging.StreamHandler() console.setLevel(logging.DEBUG) console.setFormatter(color_formatter) root_logger.addHandler(console) systemd_journal = JournalHandler() systemd_journal.setLevel(logging.DEBUG) systemd_journal.setFormatter(formatter) root_logger.addHandler(systemd_journal) logging.getLogger('celery').setLevel(logging.INFO) # Silence amqp heartbeat_tick messages logger = logging.getLogger('amqp') logger.addFilter(lambda record: not record.msg.startswith( 'heartbeat_tick')) logger.setLevel(logging.DEBUG) # Silence useless "Starting new HTTP connection" messages logging.getLogger('urllib3').setLevel(logging.WARNING) logging.getLogger('swh').setLevel(loglevel) # get_task_logger makes the swh tasks loggers children of celery.task logging.getLogger('celery.task').setLevel(loglevel) @celeryd_after_setup.connect def setup_queues_and_tasks(sender, instance, **kwargs): """Signal called on worker start. This automatically registers swh.scheduler.task.Task subclasses as available celery tasks. This also subscribes the worker to the "implicit" per-task queues defined for these task classes. """ for module_name in itertools.chain( # celery worker -I flag instance.app.conf['include'], # set from the celery / swh worker instance configuration file instance.app.conf['imports'], ): module = importlib.import_module(module_name) for name in dir(module): obj = getattr(module, name) if ( isinstance(obj, type) and issubclass(obj, Task) and obj != Task # Don't register the abstract class itself ): class_name = '%s.%s' % (module_name, name) instance.app.register_task_class(class_name, obj) for task_name in instance.app.tasks: if task_name.startswith('swh.'): instance.app.amqp.queues.select_add(task_name) @Panel.register def monotonic(state): """Get the current value for the monotonic clock""" return {'monotonic': _monotonic()} def route_for_task(name, args, kwargs, options, task=None, **kw): """Route tasks according to the task_queue attribute in the task class""" if name is not None and name.startswith('swh.'): return {'queue': name} class CustomCelery(Celery): def get_queue_stats(self, queue_name): """Get the statistics regarding a queue on the broker. Arguments: queue_name: name of the queue to check Returns a dictionary raw from the RabbitMQ management API; or `None` if the current configuration does not use RabbitMQ. Interesting keys: - consumers (number of consumers for the queue) - messages (number of messages in queue) - messages_unacknowledged (number of messages currently being processed) Documentation: https://www.rabbitmq.com/management.html#http-api """ conn_info = self.connection().info() if conn_info['transport'] == 'memory': # We're running in a test environment, without RabbitMQ. return None url = 'http://{hostname}:{port}/api/queues/{vhost}/{queue}'.format( hostname=conn_info['hostname'], port=conn_info['port'] + 10000, vhost=urllib.parse.quote(conn_info['virtual_host'], safe=''), queue=urllib.parse.quote(queue_name, safe=''), ) credentials = (conn_info['userid'], conn_info['password']) r = requests.get(url, auth=credentials) if r.status_code == 404: return {} if r.status_code != 200: raise ValueError('Got error %s when reading queue stats: %s' % ( r.status_code, r.json())) return r.json() def get_queue_length(self, queue_name): """Shortcut to get a queue's length""" stats = self.get_queue_stats(queue_name) if stats: return stats.get('messages') def register_task_class(self, name, cls): """Register a class-based task under the given name""" if name in self.tasks: return task_instance = cls() task_instance.name = name self.register_task(task_instance) INSTANCE_NAME = os.environ.get(CONFIG_NAME_ENVVAR) if INSTANCE_NAME: CONFIG_NAME = CONFIG_NAME_TEMPLATE % INSTANCE_NAME else: CONFIG_NAME = DEFAULT_CONFIG_NAME # Load the Celery config CONFIG = load_named_config(CONFIG_NAME, DEFAULT_CONFIG) # Celery Queues CELERY_QUEUES = [Queue('celery', Exchange('celery'), routing_key='celery')] for queue in CONFIG['task_queues']: CELERY_QUEUES.append(Queue(queue, Exchange(queue), routing_key=queue)) # Instantiate the Celery app app = CustomCelery() app.conf.update( # The broker broker_url=CONFIG['task_broker'], # Timezone configuration: all in UTC enable_utc=True, timezone='UTC', # Imported modules imports=CONFIG['task_modules'], # Time (in seconds, or a timedelta object) for when after stored task # tombstones will be deleted. None means to never expire results. result_expires=None, # A string identifying the default serialization method to use. Can # be json (default), pickle, yaml, msgpack, or any custom # serialization methods that have been registered with task_serializer='msgpack', # Result serialization format result_serializer='msgpack', # Late ack means the task messages will be acknowledged after the task has # been executed, not just before, which is the default behavior. task_acks_late=True, # A string identifying the default serialization method to use. # Can be pickle (default), json, yaml, msgpack or any custom serialization # methods that have been registered with kombu.serialization.registry accept_content=['msgpack', 'json'], # If True the task will report its status as “started” # when the task is executed by a worker. task_track_started=True, # Default compression used for task messages. Can be gzip, bzip2 # (if available), or any custom compression schemes registered # in the Kombu compression registry. # result_compression='bzip2', # task_compression='bzip2', # Disable all rate limits, even if tasks has explicit rate limits set. # (Disabling rate limits altogether is recommended if you don’t have any # tasks using them.) worker_disable_rate_limits=True, # Task hard time limit in seconds. The worker processing the task will be # killed and replaced with a new one when this is exceeded. # task_time_limit=3600, # Task soft time limit in seconds. # The SoftTimeLimitExceeded exception will be raised when this is exceeded. # The task can catch this to e.g. clean up before the hard time limit # comes. task_soft_time_limit=CONFIG['task_soft_time_limit'], # Task routing task_routes=route_for_task, # Task queues this worker will consume from task_queues=CELERY_QUEUES, # Allow pool restarts from remote worker_pool_restarts=True, # Do not prefetch tasks worker_prefetch_multiplier=1, # Send events worker_send_task_events=True, # Do not send useless task_sent events task_send_sent_event=False, )