Example #1
0
    def __init__(self, zk_hosts, hostname, port, join_cluster):
        self.me = '%s:%s' % (hostname, port)
        self.is_master = None
        self.slaves = cycle([])
        self.slave_count = 0
        self.started_shutdown = False

        if join_cluster:
            read_only = False
        else:
            read_only = True

        self.zk = KazooClient(hosts=zk_hosts,
                              handler=SequentialGeventHandler(),
                              read_only=read_only)
        event = self.zk.start_async()
        event.wait(timeout=5)

        self.lock = self.zk.Lock(path='/iris/sender_master',
                                 identifier=self.me)

        # Used to keep track of slaves / senders present in cluster
        self.party = Party(client=self.zk,
                           path='/iris/sender_nodes',
                           identifier=self.me)

        if join_cluster:
            self.zk.add_listener(self.event_listener)
            self.party.join()
Example #2
0
    def join_parties(self, parties=None):
        """List of parties, join them all"""
        if parties is None or not parties:
            self.log.debug("No parties to join specified")
            parties = []
        else:
            self.log.debug("Joining %s parties: %s", len(parties), ", ".join(parties))
            for party in parties:

                partypath = '%s/%s/parties/%s' % (self.BASE_ZNODE, self.session, party)
                thisparty = Party(self, partypath, self.whoami)
                thisparty.join()
                self.parties[party] = thisparty
Example #3
0
    def join_parties(self, parties=None):
        """List of parties, join them all"""
        if parties is None or not parties:
            self.log.debug("No parties to join specified")
            parties = []
        else:
            self.log.debug("Joining %s parties: %s", len(parties),
                           ", ".join(parties))
            for party in parties:

                partypath = '%s/%s/parties/%s' % (self.BASE_ZNODE,
                                                  self.session, party)
                thisparty = Party(self, partypath, self.whoami)
                thisparty.join()
                self.parties[party] = thisparty
Example #4
0
    def __init__(self, ip_port, name):
        '''Initialize everyting for the player'''
        self.name = name
        logging.basicConfig()

        try:
            # Create client
            self.zk = KazooClient(hosts=ip_port, logger=logging)
            self.zk.start()
        except Exception as ex:
            print(
                'Error connecting the Zookeeper Service, Please make sure the service is up or the IP:PORT provided is correct'
            )
            sys.exit(-1)

        # Ensure Paths
        self.zk.ensure_path('/csjain_queue')
        self.zk.ensure_path('/csjain_players')

        # Create Data structures
        self.my_queue = Queue(self.zk, '/csjain_queue')
        self.party = Party(self.zk, '/csjain_players', self.name)
Example #5
0
    def __init__(self, ip_port, score_board_size):
        '''Initialize everyting for the watcher'''
        logging.basicConfig()
        self.score_board_size = score_board_size
        self.is_dump = False
        self.is_init_client = True

        try:
            # Create client
            self.zk = KazooClient(hosts=ip_port, logger=logging)
            self.zk.start()
        except Exception as ex:
            print(
                'Error connecting the Zookeeper Service, Please make sure the service is up or the IP:PORT provided is correct'
            )
            sys.exit(-1)

        # Ensure Paths
        self.zk.ensure_path('/csjain_queue')
        self.zk.ensure_path('/csjain_players')

        # Create Data structures
        self.score_queue = Queue(self.zk, '/csjain_queue')
        self.party = Party(self.zk, '/csjain_players')
        self.online_players = set(self.party)

        if len(self.score_queue) == 0:
            print('Most recent scores')
            print('------------------')
            print('\n')
            print('Highest scores')
            print('--------------')

        # Create Watchers
        _ = ChildrenWatch(self.zk, '/csjain_queue', self.process_score)
        _ = ChildrenWatch(self.zk, '/csjain_players', self.process_client)
Example #6
0
class Player:

    name = ''

    def __init__(self, ip_port, name):
        '''Initialize everyting for the player'''
        self.name = name
        logging.basicConfig()

        try:
            # Create client
            self.zk = KazooClient(hosts=ip_port, logger=logging)
            self.zk.start()
        except Exception as ex:
            print(
                'Error connecting the Zookeeper Service, Please make sure the service is up or the IP:PORT provided is correct'
            )
            sys.exit(-1)

        # Ensure Paths
        self.zk.ensure_path('/csjain_queue')
        self.zk.ensure_path('/csjain_players')

        # Create Data structures
        self.my_queue = Queue(self.zk, '/csjain_queue')
        self.party = Party(self.zk, '/csjain_players', self.name)

    def join_party(self):
        '''Add player to list of current online players'''
        self.party.join()

    def leave_party(self):
        '''Remove player from list of current online players'''
        self.party.leave()

    def post_score(self, score):
        '''Post a random score'''
        if self.name not in set(self.party):
            self.party.join()
        self.my_queue.put('{}:{}'.format(self.name,
                                         str(score)).encode('utf-8'))
Example #7
0
class Coordinator(object):
    def __init__(self, zk_hosts, hostname, port, join_cluster):
        self.me = '%s:%s' % (hostname, port)
        self.is_master = None
        self.slaves = cycle([])
        self.slave_count = 0
        self.started_shutdown = False

        if join_cluster:
            read_only = False
        else:
            read_only = True

        self.zk = KazooClient(hosts=zk_hosts,
                              handler=SequentialGeventHandler(),
                              read_only=read_only)
        event = self.zk.start_async()
        event.wait(timeout=5)

        self.lock = self.zk.Lock(path='/iris/sender_master',
                                 identifier=self.me)

        # Used to keep track of slaves / senders present in cluster
        self.party = Party(client=self.zk,
                           path='/iris/sender_nodes',
                           identifier=self.me)

        if join_cluster:
            self.zk.add_listener(self.event_listener)
            self.party.join()

    def am_i_master(self):
        return self.is_master

    # Used for API to get the current master
    def get_current_master(self):
        try:
            contenders = self.lock.contenders()
        except kazoo.exceptions.KazooException:
            logger.exception('Failed getting contenders')
            return None

        if contenders:
            return self.address_to_tuple(contenders[0])
        else:
            return None

    # Used for API to get the current slaves if master can't be reached
    def get_current_slaves(self):
        return [self.address_to_tuple(host) for host in self.party]

    def address_to_tuple(self, address):
        try:
            host, port = address.split(':')
            return host, int(port)
        except (IndexError, ValueError):
            logger.error('Failed getting address tuple from %s', address)
            return None

    def update_status(self):
        if self.started_shutdown:
            return

        if self.zk.state == KazooState.CONNECTED:
            if self.lock.is_acquired:
                self.is_master = True
            else:
                try:
                    self.is_master = self.lock.acquire(blocking=False,
                                                       timeout=2)

                # This one is expected when we're recovering from ZK being down
                except kazoo.exceptions.CancelledError:
                    self.is_master = False

                except kazoo.exceptions.LockTimeout:
                    self.is_master = False
                    logger.exception(
                        'Failed trying to acquire lock (shouldn\'t happen as we\'re using nonblocking locks)'
                    )

                except kazoo.exceptions.KazooException:
                    self.is_master = False
                    logger.exception(
                        'ZK problem while Failed trying to acquire lock')
        else:
            logger.error('ZK connection is in %s state', self.zk.state)
            self.is_master = False

        if self.zk.state == KazooState.CONNECTED:

            if self.is_master:
                slaves = [
                    self.address_to_tuple(host) for host in self.party
                    if host != self.me
                ]
                self.slave_count = len(slaves)
                self.slaves = cycle(slaves)
            else:
                self.slaves = cycle([])
                self.slave_count = 0

            # Keep us as part of the party, so the current master sees us as a slave
            if not self.party.participating:
                try:
                    self.party.join()
                except kazoo.exceptions.KazooException:
                    logger.exception('ZK problem while trying to join party')
        else:
            self.slaves = cycle([])
            self.slave_count = 0

    def update_forever(self):
        while True:
            if self.started_shutdown:
                return

            old_status = self.is_master
            self.update_status()
            new_status = self.is_master

            if old_status != new_status:
                log = logger.info
            else:
                log = logger.debug

            if self.is_master:
                log('I am the master sender')
            else:
                log('I am a slave sender')

            metrics.set('slave_instance_count', self.slave_count)
            metrics.set('is_master_sender', int(self.is_master is True))

            sleep(UPDATE_FREQUENCY)

    def leave_cluster(self):
        self.started_shutdown = True

        # cancel any attempts to acquire master lock which could make us hang
        self.lock.cancel()

        if self.zk.state == KazooState.CONNECTED:
            if self.party and self.party.participating:
                logger.info('Leaving party')
                self.party.leave()
            if self.lock and self.lock.is_acquired:
                logger.info('Releasing lock')
                self.lock.release()

    def event_listener(self, state):
        if state == KazooState.LOST or state == KazooState.SUSPENDED:
            logger.info(
                'ZK state transitioned to %s. Resetting master status.', state)

            # cancel pending attempts to acquire lock which will break and leave
            # us in bad state
            self.lock.cancel()

            # make us try to re-acquire lock during next iteration when we're connected
            if self.lock.is_acquired:
                self.lock.is_acquired = False

            # make us try to rejoin the party during next iteration when we're connected
            if self.party.participating:
                self.party.participating = False

            # in the meantime we're not master
            self.is_master = None
Example #8
0
class Coordinator(object):
    def __init__(self, zk_hosts, hostname, port, join_cluster):
        self.me = '%s:%s' % (hostname, port)
        self.is_master = None
        self.slaves = cycle([])
        self.slave_count = 0
        self.started_shutdown = False

        if join_cluster:
            read_only = False
        else:
            read_only = True

        self.zk = KazooClient(hosts=zk_hosts,
                              handler=SequentialGeventHandler(),
                              read_only=read_only)
        event = self.zk.start_async()
        event.wait(timeout=5)

        self.lock = self.zk.Lock(path='/iris/sender_master',
                                 identifier=self.me)

        # Used to keep track of slaves / senders present in cluster
        self.party = Party(client=self.zk,
                           path='/iris/sender_nodes',
                           identifier=self.me)

        if join_cluster:
            self.party.join()

    def am_i_master(self):
        return self.is_master

    # Used for API to get the current master
    def get_current_master(self):
        try:
            contenders = self.lock.contenders()
        except kazoo.exceptions.KazooException:
            logger.exception('Failed getting contenders')
            return None

        if contenders:
            return self.address_to_tuple(contenders[0])
        else:
            return None

    # Used for API to get the current slaves if master can't be reached
    def get_current_slaves(self):
        return [self.address_to_tuple(host) for host in self.party]

    def address_to_tuple(self, address):
        try:
            host, port = address.split(':')
            return host, int(port)
        except (IndexError, ValueError):
            logger.error('Failed getting address tuple from %s', address)
            return None

    def update_status(self):
        if self.started_shutdown:
            return

        if self.zk.state == KazooState.CONNECTED:
            if self.is_master:
                self.is_master = self.lock.is_acquired
            else:
                try:
                    self.is_master = self.lock.acquire(blocking=False,
                                                       timeout=2)
                except kazoo.exceptions.LockTimeout:
                    self.is_master = False
                    logger.exception(
                        'Failed trying to acquire lock (shouldn\'t happen as we\'re using nonblocking locks)'
                    )
                except kazoo.exceptions.KazooException:
                    self.is_master = False
                    logger.exception(
                        'ZK problem while Failed trying to acquire lock')
        else:
            logger.error('ZK connection is not in connected state')
            self.is_master = False

        if self.is_master:
            slaves = [
                self.address_to_tuple(host) for host in self.party
                if host != self.me
            ]
            self.slave_count = len(slaves)
            self.slaves = cycle(slaves)
        else:
            self.slaves = cycle([])
            self.slave_count = 0

    def update_forever(self):
        while True:
            if self.started_shutdown:
                return

            old_status = self.is_master
            self.update_status()
            new_status = self.is_master

            if old_status != new_status:
                log = logger.info
            else:
                log = logger.debug

            if self.is_master:
                log('I am the master sender')
            else:
                log('I am a slave sender')

            metrics.set('slave_instance_count', self.slave_count)
            metrics.set('is_master_sender', int(self.is_master))

            sleep(UPDATE_FREQUENCY)

    def leave_cluster(self):
        self.started_shutdown = True
        if self.party and self.party.participating:
            logger.info('Leaving party')
            self.party.leave()
        if self.lock and self.lock.is_acquired:
            logger.info('Releasing lock')
            self.lock.release()
        TimeoutError: The port isn't accepting connection after time specified in `timeout`.
    """
    start_time = time.perf_counter()
    while True:
        try:
            with socket.create_connection((host, port), timeout=timeout):
                break
        except OSError as ex:
            time.sleep(0.01)
            if time.perf_counter() - start_time >= timeout:
                raise TimeoutError(
                    "Waited too long for the port {} on host {} to start accepting "
                    "connections.".format(port, host)) from ex


if __name__ == "__main__":
    # args = get_args()
    port = 80
    hostname = "127.0.0.1"
    host = f"{hostname}:{port}"
    zk = KazooClient(
        hosts=host,
        connection_retry=KazooRetry(20),
    )
    zk.start()
    party = Party(zk, "/celery/workers", identifier=1)
    print(zk.get_children("/celery/"))
    # for member in party:
    #     print(member)
    zk.stop()
Example #10
0
        elapsed = datetime.datetime.utcnow() - begun
        logging.info('assayed %d keys and %d values on server %d in %f ms',
                     c_count, v_count, server, elapsed.total_seconds * 1000.0)


def summarize_me(signum, frame):
    party_size = len(party)
    logging.info('there are %s clients in the party', party_size)
    my_position = get_my_position(party, ME)
    logging.info('my place in the party is: %d', (my_position))
    targets = get_work(party_size, my_position)
    logging.debug('%d assigned targets: %s', len(targets), targets)
    compute_averages(targets)
    # reset the alarm
    signal.alarm(1)


zk = KazooClient(hosts=ZK_HOSTS)
zk.start()
zk.add_listener(zk_state)
zk.ensure_path(PREFIX)
party = Party(zk, PREFIX, identifier=ME)
atexit.register(exit_handler, party)
party.join()

signal.signal(signal.SIGALRM, summarize_me)
signal.alarm(5)

while True:
    time.sleep(300)