Esempio n. 1
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def multicall(conf, context, topic, msg, timeout, connection_pool):
    """Make a call that returns multiple times."""
    # TODO(pekowski): Remove all these comments in Havana.
    # For amqp_rpc_single_reply_queue = False,
    # Can't use 'with' for multicall, as it returns an iterator
    # that will continue to use the connection.  When it's done,
    # connection.close() will get called which will put it back into
    # the pool
    # For amqp_rpc_single_reply_queue = True,
    # The 'with' statement is mandatory for closing the connection
    LOG.debug(_('Making synchronous call on %s ...'), topic)
    msg_id = uuid.uuid4().hex
    msg.update({'_msg_id': msg_id})
    LOG.debug(_('MSG_ID is %s') % (msg_id))
    _add_unique_id(msg)
    pack_context(msg, context)

    # TODO(pekowski): Remove this flag and the code under the if clause
    #                 in Havana.
    if not conf.amqp_rpc_single_reply_queue:
        conn = ConnectionContext(conf, connection_pool)
        wait_msg = MulticallWaiter(conf, conn, timeout)
        conn.declare_direct_consumer(msg_id, wait_msg)
        conn.topic_send(topic, rpc_common.serialize_msg(msg), timeout)
    else:
        with _reply_proxy_create_sem:
            if not connection_pool.reply_proxy:
                connection_pool.reply_proxy = ReplyProxy(conf, connection_pool)
        msg.update({'_reply_q': connection_pool.reply_proxy.get_reply_q()})
        wait_msg = MulticallProxyWaiter(conf, msg_id, timeout, connection_pool)
        with ConnectionContext(conf, connection_pool) as conn:
            conn.topic_send(topic, rpc_common.serialize_msg(msg), timeout)
    return wait_msg
Esempio n. 2
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    def _process_data(self, ctxt, version, method, args):
        """Process a message in a new thread.

        If the proxy object we have has a dispatch method
        (see rpc.dispatcher.RpcDispatcher), pass it the version,
        method, and args and let it dispatch as appropriate.  If not, use
        the old behavior of magically calling the specified method on the
        proxy we have here.
        """
        ctxt.update_store()
        try:
            rval = self.proxy.dispatch(ctxt, version, method, **args)
            # Check if the result was a generator
            if inspect.isgenerator(rval):
                for x in rval:
                    ctxt.reply(x, None, connection_pool=self.connection_pool)
            else:
                ctxt.reply(rval, None, connection_pool=self.connection_pool)
            # This final None tells multicall that it is done.
            ctxt.reply(ending=True, connection_pool=self.connection_pool)
        except rpc_common.ClientException as e:
            LOG.debug(_('Expected exception during message handling (%s)') %
                      e._exc_info[1])
            ctxt.reply(None, e._exc_info,
                       connection_pool=self.connection_pool,
                       log_failure=False)
        except Exception:
            # sys.exc_info() is deleted by LOG.exception().
            exc_info = sys.exc_info()
            LOG.error(_('Exception during message handling'),
                      exc_info=exc_info)
            ctxt.reply(None, exc_info, connection_pool=self.connection_pool)
Esempio n. 3
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            def publisher(waiter):
                LOG.info(_("Creating proxy for topic: %s"), topic)

                try:
                    # The topic is received over the network,
                    # don't trust this input.
                    if self.badchars.search(topic) is not None:
                        emsg = _("Topic contained dangerous characters.")
                        LOG.warn(emsg)
                        raise RPCException(emsg)

                    out_sock = ZmqSocket("ipc://%s/zmq_topic_%s" %
                                         (ipc_dir, topic),
                                         sock_type, bind=True)
                except RPCException:
                    waiter.send_exception(*sys.exc_info())
                    return

                self.topic_proxy[topic] = eventlet.queue.LightQueue(
                    CONF.rpc_zmq_topic_backlog)
                self.sockets.append(out_sock)

                # It takes some time for a pub socket to open,
                # before we can have any faith in doing a send() to it.
                if sock_type == zmq.PUB:
                    eventlet.sleep(.5)

                waiter.send(True)

                while(True):
                    data = self.topic_proxy[topic].get()
                    out_sock.send(data)
                    LOG.debug(_("ROUTER RELAY-OUT SUCCEEDED %(data)s") %
                              {'data': data})
Esempio n. 4
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    def _wait_child(self):
        try:
            # Don't block if no child processes have exited
            pid, status = os.waitpid(0, os.WNOHANG)
            if not pid:
                return None
        except OSError as exc:
            if exc.errno not in (errno.EINTR, errno.ECHILD):
                raise
            return None

        if os.WIFSIGNALED(status):
            sig = os.WTERMSIG(status)
            LOG.info(_('Child %(pid)d killed by signal %(sig)d'),
                     dict(pid=pid, sig=sig))
        else:
            code = os.WEXITSTATUS(status)
            LOG.info(_('Child %(pid)s exited with status %(code)d'),
                     dict(pid=pid, code=code))

        if pid not in self.children:
            LOG.warning(_('pid %d not in child list'), pid)
            return None

        wrap = self.children.pop(pid)
        wrap.children.remove(pid)
        return wrap
Esempio n. 5
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    def _process_data(self, ctxt, version, method, args):
        """Process a message in a new thread.

        If the proxy object we have has a dispatch method
        (see rpc.dispatcher.RpcDispatcher), pass it the version,
        method, and args and let it dispatch as appropriate.  If not, use
        the old behavior of magically calling the specified method on the
        proxy we have here.
        """
        ctxt.update_store()
        try:
            rval = self.proxy.dispatch(ctxt, version, method, **args)
            # Check if the result was a generator
            if inspect.isgenerator(rval):
                for x in rval:
                    ctxt.reply(x, None, connection_pool=self.connection_pool)
            else:
                ctxt.reply(rval, None, connection_pool=self.connection_pool)
            # This final None tells multicall that it is done.
            ctxt.reply(ending=True, connection_pool=self.connection_pool)
        except rpc_common.ClientException as e:
            LOG.debug(
                _('Expected exception during message handling (%s)') %
                e._exc_info[1])
            ctxt.reply(None,
                       e._exc_info,
                       connection_pool=self.connection_pool,
                       log_failure=False)
        except Exception:
            # sys.exc_info() is deleted by LOG.exception().
            exc_info = sys.exc_info()
            LOG.error(_('Exception during message handling'),
                      exc_info=exc_info)
            ctxt.reply(None, exc_info, connection_pool=self.connection_pool)
Esempio n. 6
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def _multi_send(method,
                context,
                topic,
                msg,
                timeout=None,
                envelope=False,
                _msg_id=None):
    """
    Wraps the sending of messages,
    dispatches to the matchmaker and sends
    message to all relevant hosts.
    """
    conf = CONF
    LOG.debug(_("%(msg)s") % {'msg': ' '.join(map(pformat, (topic, msg)))})

    queues = _get_matchmaker().queues(topic)
    LOG.debug(_("Sending message(s) to: %s"), queues)

    # Don't stack if we have no matchmaker results
    if len(queues) == 0:
        LOG.warn(_("No matchmaker results. Not casting."))
        # While not strictly a timeout, callers know how to handle
        # this exception and a timeout isn't too big a lie.
        raise rpc_common.Timeout(_("No match from matchmaker."))

    # This supports brokerless fanout (addresses > 1)
    for queue in queues:
        (_topic, ip_addr) = queue
        _addr = "tcp://%s:%s" % (ip_addr, conf.rpc_zmq_port)

        if method.__name__ == '_cast':
            eventlet.spawn_n(method, _addr, context, _topic, msg, timeout,
                             envelope, _msg_id)
            return
        return method(_addr, context, _topic, msg, timeout, envelope)
Esempio n. 7
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    def __call__(self, message_data):
        """Consumer callback to call a method on a proxy object.

        Parses the message for validity and fires off a thread to call the
        proxy object method.

        Message data should be a dictionary with two keys:
            method: string representing the method to call
            args: dictionary of arg: value

        Example: {'method': 'echo', 'args': {'value': 42}}

        """
        # It is important to clear the context here, because at this point
        # the previous context is stored in local.store.context
        if hasattr(local.store, 'context'):
            del local.store.context
        rpc_common._safe_log(LOG.debug, _('received %s'), message_data)
        self.msg_id_cache.check_duplicate_message(message_data)
        ctxt = unpack_context(self.conf, message_data)
        method = message_data.get('method')
        args = message_data.get('args', {})
        version = message_data.get('version', None)
        if not method:
            LOG.warn(_('no method for message: %s') % message_data)
            ctxt.reply(_('No method for message: %s') % message_data,
                       connection_pool=self.connection_pool)
            return
        self.pool.spawn_n(self._process_data, ctxt, version, method, args)
Esempio n. 8
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    def create_consumer(self, topic, proxy, fanout=False):
        # Register with matchmaker.
        _get_matchmaker().register(topic, CONF.rpc_zmq_host)

        # Subscription scenarios
        if fanout:
            sock_type = zmq.SUB
            subscribe = ('', fanout)[type(fanout) == str]
            topic = 'fanout~' + topic.split('.', 1)[0]
        else:
            sock_type = zmq.PULL
            subscribe = None
            topic = '.'.join((topic.split('.', 1)[0], CONF.rpc_zmq_host))

        if topic in self.topics:
            LOG.info(_("Skipping topic registration. Already registered."))
            return

        # Receive messages from (local) proxy
        inaddr = "ipc://%s/zmq_topic_%s" % \
            (CONF.rpc_zmq_ipc_dir, topic)

        LOG.debug(_("Consumer is a zmq.%s"), ['PULL',
                                              'SUB'][sock_type == zmq.SUB])

        self.reactor.register(proxy,
                              inaddr,
                              sock_type,
                              subscribe=subscribe,
                              in_bind=False)
        self.topics.append(topic)
Esempio n. 9
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    def consume(self, sock):
        # TODO(ewindisch): use zero-copy (i.e. references, not copying)
        data = sock.recv()
        LOG.debug(_("CONSUMER RECEIVED DATA: %s"), data)
        if sock in self.mapping:
            LOG.debug(_("ROUTER RELAY-OUT %(data)s") % {'data': data})
            self.mapping[sock].send(data)
            return

        proxy = self.proxies[sock]

        if data[2] == 'cast':  # Legacy protocol
            packenv = data[3]

            ctx, msg = _deserialize(packenv)
            request = rpc_common.deserialize_msg(msg)
            ctx = RpcContext.unmarshal(ctx)
        elif data[2] == 'impl_zmq_v2':
            packenv = data[4:]

            msg = unflatten_envelope(packenv)
            request = rpc_common.deserialize_msg(msg)

            # Unmarshal only after verifying the message.
            ctx = RpcContext.unmarshal(data[3])
        else:
            LOG.error(_("ZMQ Envelope version unsupported or unknown."))
            return

        self.pool.spawn_n(self.process, proxy, ctx, request)
Esempio n. 10
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    def consume_in_thread(self):
        """Runs the ZmqProxy service"""
        ipc_dir = CONF.rpc_zmq_ipc_dir
        consume_in = "tcp://%s:%s" % \
            (CONF.rpc_zmq_bind_address,
             CONF.rpc_zmq_port)
        consumption_proxy = InternalContext(None)

        if not os.path.isdir(ipc_dir):
            try:
                utils.execute('mkdir', '-p', ipc_dir, run_as_root=True)
                utils.execute('chown',
                              "%s:%s" % (os.getuid(), os.getgid()),
                              ipc_dir,
                              run_as_root=True)
                utils.execute('chmod', '750', ipc_dir, run_as_root=True)
            except utils.ProcessExecutionError:
                with excutils.save_and_reraise_exception():
                    LOG.error(
                        _("Could not create IPC directory %s") % (ipc_dir, ))

        try:
            self.register(consumption_proxy,
                          consume_in,
                          zmq.PULL,
                          out_bind=True)
        except zmq.ZMQError:
            with excutils.save_and_reraise_exception():
                LOG.error(
                    _("Could not create ZeroMQ receiver daemon. "
                      "Socket may already be in use."))

        super(ZmqProxy, self).consume_in_thread()
Esempio n. 11
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def multicall(conf, context, topic, msg, timeout, connection_pool):
    """Make a call that returns multiple times."""
    # TODO(pekowski): Remove all these comments in Havana.
    # For amqp_rpc_single_reply_queue = False,
    # Can't use 'with' for multicall, as it returns an iterator
    # that will continue to use the connection.  When it's done,
    # connection.close() will get called which will put it back into
    # the pool
    # For amqp_rpc_single_reply_queue = True,
    # The 'with' statement is mandatory for closing the connection
    LOG.debug(_('Making synchronous call on %s ...'), topic)
    msg_id = uuid.uuid4().hex
    msg.update({'_msg_id': msg_id})
    LOG.debug(_('MSG_ID is %s') % (msg_id))
    _add_unique_id(msg)
    pack_context(msg, context)

    # TODO(pekowski): Remove this flag and the code under the if clause
    #                 in Havana.
    if not conf.amqp_rpc_single_reply_queue:
        conn = ConnectionContext(conf, connection_pool)
        wait_msg = MulticallWaiter(conf, conn, timeout)
        conn.declare_direct_consumer(msg_id, wait_msg)
        conn.topic_send(topic, rpc_common.serialize_msg(msg), timeout)
    else:
        with _reply_proxy_create_sem:
            if not connection_pool.reply_proxy:
                connection_pool.reply_proxy = ReplyProxy(conf, connection_pool)
        msg.update({'_reply_q': connection_pool.reply_proxy.get_reply_q()})
        wait_msg = MulticallProxyWaiter(conf, msg_id, timeout, connection_pool)
        with ConnectionContext(conf, connection_pool) as conn:
            conn.topic_send(topic, rpc_common.serialize_msg(msg), timeout)
    return wait_msg
Esempio n. 12
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    def __init__(self, addr, zmq_type, bind=True, subscribe=None):
        self.sock = _get_ctxt().socket(zmq_type)
        self.addr = addr
        self.type = zmq_type
        self.subscriptions = []

        # Support failures on sending/receiving on wrong socket type.
        self.can_recv = zmq_type in (zmq.PULL, zmq.SUB)
        self.can_send = zmq_type in (zmq.PUSH, zmq.PUB)
        self.can_sub = zmq_type in (zmq.SUB, )

        # Support list, str, & None for subscribe arg (cast to list)
        do_sub = {
            list: subscribe,
            str: [subscribe],
            type(None): []
        }[type(subscribe)]

        for f in do_sub:
            self.subscribe(f)

        str_data = {'addr': addr, 'type': self.socket_s(),
                    'subscribe': subscribe, 'bind': bind}

        LOG.debug(_("Connecting to %(addr)s with %(type)s"), str_data)
        LOG.debug(_("-> Subscribed to %(subscribe)s"), str_data)
        LOG.debug(_("-> bind: %(bind)s"), str_data)

        try:
            if bind:
                self.sock.bind(addr)
            else:
                self.sock.connect(addr)
        except Exception:
            raise RPCException(_("Could not open socket."))
Esempio n. 13
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 def _connect(self, params):
     """Connect to rabbit.  Re-establish any queues that may have
     been declared before if we are reconnecting.  Exceptions should
     be handled by the caller.
     """
     if self.connection:
         LOG.info(_("Reconnecting to AMQP server on "
                  "%(hostname)s:%(port)d") % params)
         try:
             self.connection.release()
         except self.connection_errors:
             pass
         # Setting this in case the next statement fails, though
         # it shouldn't be doing any network operations, yet.
         self.connection = None
     self.connection = kombu.connection.BrokerConnection(**params)
     self.connection_errors = self.connection.connection_errors
     if self.memory_transport:
         # Kludge to speed up tests.
         self.connection.transport.polling_interval = 0.0
     self.consumer_num = itertools.count(1)
     self.connection.connect()
     self.channel = self.connection.channel()
     # work around 'memory' transport bug in 1.1.3
     if self.memory_transport:
         self.channel._new_queue('ae.undeliver')
     for consumer in self.consumers:
         consumer.reconnect(self.channel)
     LOG.info(_('Connected to AMQP server on %(hostname)s:%(port)d') %
              params)
Esempio n. 14
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    def consume_in_thread(self):
        """Runs the ZmqProxy service"""
        ipc_dir = CONF.rpc_zmq_ipc_dir
        consume_in = "tcp://%s:%s" % \
            (CONF.rpc_zmq_bind_address,
             CONF.rpc_zmq_port)
        consumption_proxy = InternalContext(None)

        if not os.path.isdir(ipc_dir):
            try:
                utils.execute('mkdir', '-p', ipc_dir, run_as_root=True)
                utils.execute('chown', "%s:%s" % (os.getuid(), os.getgid()),
                              ipc_dir, run_as_root=True)
                utils.execute('chmod', '750', ipc_dir, run_as_root=True)
            except utils.ProcessExecutionError:
                with excutils.save_and_reraise_exception():
                    LOG.error(_("Could not create IPC directory %s") %
                              (ipc_dir, ))

        try:
            self.register(consumption_proxy,
                          consume_in,
                          zmq.PULL,
                          out_bind=True)
        except zmq.ZMQError:
            with excutils.save_and_reraise_exception():
                LOG.error(_("Could not create ZeroMQ receiver daemon. "
                            "Socket may already be in use."))

        super(ZmqProxy, self).consume_in_thread()
Esempio n. 15
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    def run_periodic_tasks(self, context, raise_on_error=False):
        """Tasks to be run at a periodic interval."""
        for task_name, task in self._periodic_tasks:
            full_task_name = '.'.join([self.__class__.__name__, task_name])

            ticks_to_skip = self._ticks_to_skip[task_name]
            if ticks_to_skip > 0:
                LOG.debug(_("Skipping %(full_task_name)s, %(ticks_to_skip)s"
                            " ticks left until next run"),
                          dict(full_task_name=full_task_name,
                               ticks_to_skip=ticks_to_skip))
                self._ticks_to_skip[task_name] -= 1
                continue

            self._ticks_to_skip[task_name] = task._ticks_between_runs
            LOG.debug(_("Running periodic task %(full_task_name)s"),
                      dict(full_task_name=full_task_name))

            try:
                task(self, context)
            except Exception as e:
                if raise_on_error:
                    raise
                LOG.exception(_("Error during %(full_task_name)s:"
                                " %(e)s"),
                              dict(e=e, full_task_name=full_task_name))
Esempio n. 16
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    def __call__(self, message_data):
        """Consumer callback to call a method on a proxy object.

        Parses the message for validity and fires off a thread to call the
        proxy object method.

        Message data should be a dictionary with two keys:
            method: string representing the method to call
            args: dictionary of arg: value

        Example: {'method': 'echo', 'args': {'value': 42}}

        """
        # It is important to clear the context here, because at this point
        # the previous context is stored in local.store.context
        if hasattr(local.store, 'context'):
            del local.store.context
        rpc_common._safe_log(LOG.debug, _('received %s'), message_data)
        self.msg_id_cache.check_duplicate_message(message_data)
        ctxt = unpack_context(self.conf, message_data)
        method = message_data.get('method')
        args = message_data.get('args', {})
        version = message_data.get('version', None)
        if not method:
            LOG.warn(_('no method for message: %s') % message_data)
            ctxt.reply(_('No method for message: %s') % message_data,
                       connection_pool=self.connection_pool)
            return
        self.pool.spawn_n(self._process_data, ctxt, version, method, args)
Esempio n. 17
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def execute(cmd, root_helper=None, process_input=None, addl_env=None,
            check_exit_code=True, return_stderr=False):
    if root_helper:
        cmd = shlex.split(root_helper) + cmd
    cmd = map(str, cmd)

    LOG.debug(_("Running command: %s"), cmd)
    env = os.environ.copy()
    if addl_env:
        env.update(addl_env)
    obj = subprocess_popen(cmd, shell=False,
                           stdin=subprocess.PIPE,
                           stdout=subprocess.PIPE,
                           stderr=subprocess.PIPE,
                           env=env)

    _stdout, _stderr = (process_input and
                        obj.communicate(process_input) or
                        obj.communicate())
    obj.stdin.close()
    m = _("\nCommand: %(cmd)s\nExit code: %(code)s\nStdout: %(stdout)r\n"
          "Stderr: %(stderr)r") % {'cmd': cmd, 'code': obj.returncode,
                                   'stdout': _stdout, 'stderr': _stderr}
    LOG.debug(m)
    if obj.returncode and check_exit_code:
        raise RuntimeError(m)

    return return_stderr and (_stdout, _stderr) or _stdout
Esempio n. 18
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    def create_consumer(self, topic, proxy, fanout=False):
        # Register with matchmaker.
        _get_matchmaker().register(topic, CONF.rpc_zmq_host)

        # Subscription scenarios
        if fanout:
            sock_type = zmq.SUB
            subscribe = ('', fanout)[type(fanout) == str]
            topic = 'fanout~' + topic.split('.', 1)[0]
        else:
            sock_type = zmq.PULL
            subscribe = None
            topic = '.'.join((topic.split('.', 1)[0], CONF.rpc_zmq_host))

        if topic in self.topics:
            LOG.info(_("Skipping topic registration. Already registered."))
            return

        # Receive messages from (local) proxy
        inaddr = "ipc://%s/zmq_topic_%s" % \
            (CONF.rpc_zmq_ipc_dir, topic)

        LOG.debug(_("Consumer is a zmq.%s"),
                  ['PULL', 'SUB'][sock_type == zmq.SUB])

        self.reactor.register(proxy, inaddr, sock_type,
                              subscribe=subscribe, in_bind=False)
        self.topics.append(topic)
Esempio n. 19
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def _multi_send(method, context, topic, msg, timeout=None,
                envelope=False, _msg_id=None):
    """
    Wraps the sending of messages,
    dispatches to the matchmaker and sends
    message to all relevant hosts.
    """
    conf = CONF
    LOG.debug(_("%(msg)s") % {'msg': ' '.join(map(pformat, (topic, msg)))})

    queues = _get_matchmaker().queues(topic)
    LOG.debug(_("Sending message(s) to: %s"), queues)

    # Don't stack if we have no matchmaker results
    if len(queues) == 0:
        LOG.warn(_("No matchmaker results. Not casting."))
        # While not strictly a timeout, callers know how to handle
        # this exception and a timeout isn't too big a lie.
        raise rpc_common.Timeout(_("No match from matchmaker."))

    # This supports brokerless fanout (addresses > 1)
    for queue in queues:
        (_topic, ip_addr) = queue
        _addr = "tcp://%s:%s" % (ip_addr, conf.rpc_zmq_port)

        if method.__name__ == '_cast':
            eventlet.spawn_n(method, _addr, context,
                             _topic, msg, timeout, envelope,
                             _msg_id)
            return
        return method(_addr, context, _topic, msg, timeout,
                      envelope)
Esempio n. 20
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    def reconnect(self):
        """Handles reconnecting and re-establishing sessions and queues"""
        if self.connection.opened():
            try:
                self.connection.close()
            except qpid_exceptions.ConnectionError:
                pass

        attempt = 0
        delay = 1
        while True:
            broker = self.brokers[attempt % len(self.brokers)]
            attempt += 1

            try:
                self.connection_create(broker)
                self.connection.open()
            except qpid_exceptions.ConnectionError, e:
                msg_dict = dict(e=e, delay=delay)
                msg = _("Unable to connect to AMQP server: %(e)s. "
                        "Sleeping %(delay)s seconds") % msg_dict
                LOG.error(msg)
                time.sleep(delay)
                delay = min(2 * delay, 60)
            else:
                LOG.info(_('Connected to AMQP server on %s'), broker)
                break
Esempio n. 21
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    def consume(self, sock):
        # TODO(ewindisch): use zero-copy (i.e. references, not copying)
        data = sock.recv()
        LOG.debug(_("CONSUMER RECEIVED DATA: %s"), data)
        if sock in self.mapping:
            LOG.debug(_("ROUTER RELAY-OUT %(data)s") % {
                'data': data})
            self.mapping[sock].send(data)
            return

        proxy = self.proxies[sock]

        if data[2] == 'cast':  # Legacy protocol
            packenv = data[3]

            ctx, msg = _deserialize(packenv)
            request = rpc_common.deserialize_msg(msg)
            ctx = RpcContext.unmarshal(ctx)
        elif data[2] == 'impl_zmq_v2':
            packenv = data[4:]

            msg = unflatten_envelope(packenv)
            request = rpc_common.deserialize_msg(msg)

            # Unmarshal only after verifying the message.
            ctx = RpcContext.unmarshal(data[3])
        else:
            LOG.error(_("ZMQ Envelope version unsupported or unknown."))
            return

        self.pool.spawn_n(self.process, proxy, ctx, request)
Esempio n. 22
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 def _connect(self, params):
     """Connect to rabbit.  Re-establish any queues that may have
     been declared before if we are reconnecting.  Exceptions should
     be handled by the caller.
     """
     if self.connection:
         LOG.info(
             _("Reconnecting to AMQP server on "
               "%(hostname)s:%(port)d") % params)
         try:
             self.connection.release()
         except self.connection_errors:
             pass
         # Setting this in case the next statement fails, though
         # it shouldn't be doing any network operations, yet.
         self.connection = None
     self.connection = kombu.connection.BrokerConnection(**params)
     self.connection_errors = self.connection.connection_errors
     if self.memory_transport:
         # Kludge to speed up tests.
         self.connection.transport.polling_interval = 0.0
     self.consumer_num = itertools.count(1)
     self.connection.connect()
     self.channel = self.connection.channel()
     # work around 'memory' transport bug in 1.1.3
     if self.memory_transport:
         self.channel._new_queue('ae.undeliver')
     for consumer in self.consumers:
         consumer.reconnect(self.channel)
     LOG.info(
         _('Connected to AMQP server on %(hostname)s:%(port)d') % params)
Esempio n. 23
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    def register(self, proxy, in_addr, zmq_type_in, out_addr=None,
                 zmq_type_out=None, in_bind=True, out_bind=True,
                 subscribe=None):

        LOG.info(_("Registering reactor"))

        if zmq_type_in not in (zmq.PULL, zmq.SUB):
            raise RPCException("Bad input socktype")

        # Items push in.
        inq = ZmqSocket(in_addr, zmq_type_in, bind=in_bind,
                        subscribe=subscribe)

        self.proxies[inq] = proxy
        self.sockets.append(inq)

        LOG.info(_("In reactor registered"))

        if not out_addr:
            return

        if zmq_type_out not in (zmq.PUSH, zmq.PUB):
            raise RPCException("Bad output socktype")

        # Items push out.
        outq = ZmqSocket(out_addr, zmq_type_out, bind=out_bind)

        self.mapping[inq] = outq
        self.mapping[outq] = inq
        self.sockets.append(outq)

        LOG.info(_("Out reactor registered"))
Esempio n. 24
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    def wait(self):
        """Loop waiting on children to die and respawning as necessary"""

        LOG.debug(_('Full set of CONF:'))
        CONF.log_opt_values(LOG, std_logging.DEBUG)

        while self.running:
            wrap = self._wait_child()
            if not wrap:
                # Yield to other threads if no children have exited
                # Sleep for a short time to avoid excessive CPU usage
                # (see bug #1095346)
                eventlet.greenthread.sleep(.01)
                continue

            while self.running and len(wrap.children) < wrap.workers:
                self._start_child(wrap)

        if self.sigcaught:
            signame = {signal.SIGTERM: 'SIGTERM',
                       signal.SIGINT: 'SIGINT'}[self.sigcaught]
            LOG.info(_('Caught %s, stopping children'), signame)

        for pid in self.children:
            try:
                os.kill(pid, signal.SIGTERM)
            except OSError as exc:
                if exc.errno != errno.ESRCH:
                    raise

        # Wait for children to die
        if self.children:
            LOG.info(_('Waiting on %d children to exit'), len(self.children))
            while self.children:
                self._wait_child()
Esempio n. 25
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    def reconnect(self):
        """Handles reconnecting and re-establishing sessions and queues"""
        if self.connection.opened():
            try:
                self.connection.close()
            except qpid_exceptions.ConnectionError:
                pass

        attempt = 0
        delay = 1
        while True:
            broker = self.brokers[attempt % len(self.brokers)]
            attempt += 1

            try:
                self.connection_create(broker)
                self.connection.open()
            except qpid_exceptions.ConnectionError, e:
                msg_dict = dict(e=e, delay=delay)
                msg = _("Unable to connect to AMQP server: %(e)s. "
                        "Sleeping %(delay)s seconds") % msg_dict
                LOG.error(msg)
                time.sleep(delay)
                delay = min(2 * delay, 60)
            else:
                LOG.info(_('Connected to AMQP server on %s'), broker)
                break
Esempio n. 26
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 def unplug(self, device_name, bridge=None, namespace=None, prefix=None):
     """Unplug the interface."""
     device = ip_lib.IPDevice(device_name, self.root_helper, namespace)
     try:
         device.link.delete()
         LOG.debug(_("Unplugged interface '%s'"), device_name)
     except RuntimeError:
         LOG.error(_("Failed unplugging interface '%s'"), device_name)
Esempio n. 27
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 def _error_callback(exc):
     if isinstance(exc, qpid_exceptions.Empty):
         LOG.debug(
             _('Timed out waiting for RPC response: %s') % str(exc))
         raise rpc_common.Timeout()
     else:
         LOG.exception(
             _('Failed to consume message from queue: %s') % str(exc))
Esempio n. 28
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 def _error_callback(exc):
     if isinstance(exc, qpid_exceptions.Empty):
         LOG.debug(_('Timed out waiting for RPC response: %s') %
                   str(exc))
         raise rpc_common.Timeout()
     else:
         LOG.exception(_('Failed to consume message from queue: %s') %
                       str(exc))
Esempio n. 29
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 def _error_callback(exc):
     if isinstance(exc, socket.timeout):
         LOG.debug(
             _('Timed out waiting for RPC response: %s') % str(exc))
         raise rpc_common.Timeout()
     else:
         LOG.exception(
             _('Failed to consume message from queue: %s') % str(exc))
         info['do_consume'] = True
Esempio n. 30
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 def unplug(self, device_name, bridge=None, namespace=None, prefix=None):
     """Unplug the interface."""
     device = ip_lib.IPDevice(device_name, self.root_helper, namespace)
     try:
         device.link.delete()
         LOG.debug(_("Unplugged interface '%s'"), device_name)
     except RuntimeError:
         LOG.error(_("Failed unplugging interface '%s'"),
                   device_name)
Esempio n. 31
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 def _error_callback(exc):
     if isinstance(exc, socket.timeout):
         LOG.debug(_('Timed out waiting for RPC response: %s') %
                   str(exc))
         raise rpc_common.Timeout()
     else:
         LOG.exception(_('Failed to consume message from queue: %s') %
                       str(exc))
         info['do_consume'] = True
Esempio n. 32
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    def reconnect(self):
        """Handles reconnecting and re-establishing queues.
        Will retry up to self.max_retries number of times.
        self.max_retries = 0 means to retry forever.
        Sleep between tries, starting at self.interval_start
        seconds, backing off self.interval_stepping number of seconds
        each attempt.
        """

        attempt = 0
        while True:
            params = self.params_list[attempt % len(self.params_list)]
            attempt += 1
            try:
                self._connect(params)
                return
            except (IOError, self.connection_errors) as e:
                pass
            except Exception, e:
                # NOTE(comstud): Unfortunately it's possible for amqplib
                # to return an error not covered by its transport
                # connection_errors in the case of a timeout waiting for
                # a protocol response.  (See paste link in LP888621)
                # So, we check all exceptions for 'timeout' in them
                # and try to reconnect in this case.
                if 'timeout' not in str(e):
                    raise

            log_info = {}
            log_info['err_str'] = str(e)
            log_info['max_retries'] = self.max_retries
            log_info.update(params)

            if self.max_retries and attempt == self.max_retries:
                LOG.error(
                    _('Unable to connect to AMQP server on '
                      '%(hostname)s:%(port)d after %(max_retries)d '
                      'tries: %(err_str)s') % log_info)
                # NOTE(comstud): Copied from original code.  There's
                # really no better recourse because if this was a queue we
                # need to consume on, we have no way to consume anymore.
                sys.exit(1)

            if attempt == 1:
                sleep_time = self.interval_start or 1
            elif attempt > 1:
                sleep_time += self.interval_stepping
            if self.interval_max:
                sleep_time = min(sleep_time, self.interval_max)

            log_info['sleep_time'] = sleep_time
            LOG.error(
                _('AMQP server on %(hostname)s:%(port)d is '
                  'unreachable: %(err_str)s. Trying again in '
                  '%(sleep_time)d seconds.') % log_info)
            time.sleep(sleep_time)
Esempio n. 33
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def notify(context, publisher_id, event_type, priority, payload):
    """Sends a notification using the specified driver

    :param publisher_id: the source worker_type.host of the message
    :param event_type:   the literal type of event (ex. Instance Creation)
    :param priority:     patterned after the enumeration of Python logging
                         levels in the set (DEBUG, WARN, INFO, ERROR, CRITICAL)
    :param payload:       A python dictionary of attributes

    Outgoing message format includes the above parameters, and appends the
    following:

    message_id
      a UUID representing the id for this notification

    timestamp
      the GMT timestamp the notification was sent at

    The composite message will be constructed as a dictionary of the above
    attributes, which will then be sent via the transport mechanism defined
    by the driver.

    Message example::

        {'message_id': str(uuid.uuid4()),
         'publisher_id': 'compute.host1',
         'timestamp': timeutils.utcnow(),
         'priority': 'WARN',
         'event_type': 'compute.create_instance',
         'payload': {'instance_id': 12, ... }}

    """
    if priority not in log_levels:
        raise BadPriorityException(
            _('%s not in valid priorities') % priority)

    # Ensure everything is JSON serializable.
    payload = jsonutils.to_primitive(payload, convert_instances=True)

    msg = dict(message_id=str(uuid.uuid4()),
               publisher_id=publisher_id,
               event_type=event_type,
               priority=priority,
               payload=payload,
               timestamp=str(timeutils.utcnow()))

    for driver in _get_drivers():
        try:
            driver.notify(context, msg)
        except Exception as e:
            LOG.exception(_("Problem '%(e)s' attempting to "
                            "send to notification system. "
                            "Payload=%(payload)s")
                          % dict(e=e, payload=payload))
Esempio n. 34
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    def reconnect(self):
        """Handles reconnecting and re-establishing queues.
        Will retry up to self.max_retries number of times.
        self.max_retries = 0 means to retry forever.
        Sleep between tries, starting at self.interval_start
        seconds, backing off self.interval_stepping number of seconds
        each attempt.
        """

        attempt = 0
        while True:
            params = self.params_list[attempt % len(self.params_list)]
            attempt += 1
            try:
                self._connect(params)
                return
            except (IOError, self.connection_errors) as e:
                pass
            except Exception, e:
                # NOTE(comstud): Unfortunately it's possible for amqplib
                # to return an error not covered by its transport
                # connection_errors in the case of a timeout waiting for
                # a protocol response.  (See paste link in LP888621)
                # So, we check all exceptions for 'timeout' in them
                # and try to reconnect in this case.
                if 'timeout' not in str(e):
                    raise

            log_info = {}
            log_info['err_str'] = str(e)
            log_info['max_retries'] = self.max_retries
            log_info.update(params)

            if self.max_retries and attempt == self.max_retries:
                LOG.error(_('Unable to connect to AMQP server on '
                            '%(hostname)s:%(port)d after %(max_retries)d '
                            'tries: %(err_str)s') % log_info)
                # NOTE(comstud): Copied from original code.  There's
                # really no better recourse because if this was a queue we
                # need to consume on, we have no way to consume anymore.
                sys.exit(1)

            if attempt == 1:
                sleep_time = self.interval_start or 1
            elif attempt > 1:
                sleep_time += self.interval_stepping
            if self.interval_max:
                sleep_time = min(sleep_time, self.interval_max)

            log_info['sleep_time'] = sleep_time
            LOG.error(_('AMQP server on %(hostname)s:%(port)d is '
                        'unreachable: %(err_str)s. Trying again in '
                        '%(sleep_time)d seconds.') % log_info)
            time.sleep(sleep_time)
Esempio n. 35
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 def deprecated(self, msg, *args, **kwargs):
     stdmsg = _("Deprecated: %s") % msg
     if CONF.fatal_deprecations:
         self.critical(stdmsg, *args, **kwargs)
         raise DeprecatedConfig(msg=stdmsg)
     else:
         self.warn(stdmsg, *args, **kwargs)
Esempio n. 36
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    def reply(self,
              ctx,
              proxy,
              msg_id=None,
              context=None,
              topic=None,
              msg=None):
        """Reply to a casted call."""
        # Our real method is curried into msg['args']

        child_ctx = RpcContext.unmarshal(msg[0])
        response = ConsumerBase.normalize_reply(
            self._get_response(child_ctx, proxy, topic, msg[1]), ctx.replies)

        LOG.debug(_("Sending reply"))
        _multi_send(
            _cast,
            ctx,
            topic,
            {
                'method': '-process_reply',
                'args': {
                    'msg_id': msg_id,  # Include for Folsom compat.
                    'response': response
                }
            },
            _msg_id=msg_id)
Esempio n. 37
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class InternalContext(object):
    """Used by ConsumerBase as a private context for - methods."""
    def __init__(self, proxy):
        self.proxy = proxy
        self.msg_waiter = None

    def _get_response(self, ctx, proxy, topic, data):
        """Process a curried message and cast the result to topic."""
        LOG.debug(_("Running func with context: %s"), ctx.to_dict())
        data.setdefault('version', None)
        data.setdefault('args', {})

        try:
            result = proxy.dispatch(ctx, data['version'], data['method'],
                                    **data['args'])
            return ConsumerBase.normalize_reply(result, ctx.replies)
        except greenlet.GreenletExit:
            # ignore these since they are just from shutdowns
            pass
        except rpc_common.ClientException, e:
            LOG.debug(
                _("Expected exception during message handling (%s)") %
                e._exc_info[1])
            return {
                'exc':
                rpc_common.serialize_remote_exception(e._exc_info,
                                                      log_failure=False)
            }
        except Exception:
            LOG.error(_("Exception during message handling"))
            return {
                'exc': rpc_common.serialize_remote_exception(sys.exc_info())
            }
Esempio n. 38
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 def run_vsctl(self, args):
     full_args = ["ovs-vsctl", "--timeout=2"] + args
     try:
         return utils.execute(full_args, root_helper=self.root_helper)
     except Exception, e:
         LOG.error(_("Unable to execute %(cmd)s. Exception: %(exception)s"),
                   {'cmd': full_args, 'exception': e})
Esempio n. 39
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    def start(self, interval, initial_delay=None):
        self._running = True
        done = event.Event()

        def _inner():
            if initial_delay:
                greenthread.sleep(initial_delay)

            try:
                while self._running:
                    start = timeutils.utcnow()
                    self.f(*self.args, **self.kw)
                    end = timeutils.utcnow()
                    if not self._running:
                        break
                    delay = interval - timeutils.delta_seconds(start, end)
                    if delay <= 0:
                        LOG.warn(_('task run outlasted interval by %s sec') %
                                 -delay)
                    greenthread.sleep(delay if delay > 0 else 0)
            except LoopingCallDone, e:
                self.stop()
                done.send(e.retvalue)
            except Exception:
                LOG.exception(_('in looping call'))
                done.send_exception(*sys.exc_info())
                return
Esempio n. 40
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    def _build_flow_expr_arr(self, **kwargs):
        flow_expr_arr = []
        is_delete_expr = kwargs.get('delete', False)
        if not is_delete_expr:
            prefix = ("hard_timeout=%s,idle_timeout=%s,priority=%s" %
                      (kwargs.get('hard_timeout', '0'),
                       kwargs.get('idle_timeout', '0'),
                       kwargs.get('priority', '1')))
            flow_expr_arr.append(prefix)
        elif 'priority' in kwargs:
            raise Exception(_("Cannot match priority on flow deletion"))

        in_port = ('in_port' in kwargs and ",in_port=%s" %
                   kwargs['in_port'] or '')
        dl_type = ('dl_type' in kwargs and ",dl_type=%s" %
                   kwargs['dl_type'] or '')
        dl_vlan = ('dl_vlan' in kwargs and ",dl_vlan=%s" %
                   kwargs['dl_vlan'] or '')
        dl_src = 'dl_src' in kwargs and ",dl_src=%s" % kwargs['dl_src'] or ''
        dl_dst = 'dl_dst' in kwargs and ",dl_dst=%s" % kwargs['dl_dst'] or ''
        nw_src = 'nw_src' in kwargs and ",nw_src=%s" % kwargs['nw_src'] or ''
        nw_dst = 'nw_dst' in kwargs and ",nw_dst=%s" % kwargs['nw_dst'] or ''
        tun_id = 'tun_id' in kwargs and ",tun_id=%s" % kwargs['tun_id'] or ''
        proto = 'proto' in kwargs and ",%s" % kwargs['proto'] or ''
        ip = ('nw_src' in kwargs or 'nw_dst' in kwargs) and ',ip' or ''
        match = (in_port + dl_type + dl_vlan + dl_src + dl_dst +
                 (ip or proto) + nw_src + nw_dst + tun_id)
        if match:
            match = match[1:]  # strip leading comma
            flow_expr_arr.append(match)
        return flow_expr_arr
Esempio n. 41
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def get_bridges(root_helper):
    args = ["ovs-vsctl", "--timeout=2", "list-br"]
    try:
        return utils.execute(args, root_helper=root_helper).strip().split("\n")
    except Exception, e:
        LOG.exception(_("Unable to retrieve bridges. Exception: %s"), e)
        return []
Esempio n. 42
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def cast(conf, context, topic, msg, connection_pool):
    """Sends a message on a topic without waiting for a response."""
    LOG.debug(_('Making asynchronous cast on %s...'), topic)
    _add_unique_id(msg)
    pack_context(msg, context)
    with ConnectionContext(conf, connection_pool) as conn:
        conn.topic_send(topic, rpc_common.serialize_msg(msg))
Esempio n. 43
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 def run_ofctl(self, cmd, args):
     full_args = ["ovs-ofctl", cmd, self.br_name] + args
     try:
         return utils.execute(full_args, root_helper=self.root_helper)
     except Exception, e:
         LOG.error(_("Unable to execute %(cmd)s. Exception: %(exception)s"),
                   {'cmd': full_args, 'exception': e})
Esempio n. 44
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    def plug(self,
             network_id,
             port_id,
             device_name,
             mac_address,
             bridge=None,
             namespace=None,
             prefix=None):
        """Plugin the interface."""
        if not ip_lib.device_exists(
                device_name, self.root_helper, namespace=namespace):
            ip = ip_lib.IPWrapper(self.root_helper)

            # Enable agent to define the prefix
            if prefix:
                tap_name = device_name.replace(prefix, 'tap')
            else:
                tap_name = device_name.replace(self.DEV_NAME_PREFIX, 'tap')
            root_veth, ns_veth = ip.add_veth(tap_name, device_name)
            ns_veth.link.set_address(mac_address)

            if self.conf.network_device_mtu:
                root_veth.link.set_mtu(self.conf.network_device_mtu)
                ns_veth.link.set_mtu(self.conf.network_device_mtu)

            if namespace:
                namespace_obj = ip.ensure_namespace(namespace)
                namespace_obj.add_device_to_namespace(ns_veth)

            root_veth.link.set_up()
            ns_veth.link.set_up()

        else:
            LOG.warn(_("Device %s already exists"), device_name)
Esempio n. 45
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def fanout_cast(conf, context, topic, msg, connection_pool):
    """Sends a message on a fanout exchange without waiting for a response."""
    LOG.debug(_('Making asynchronous fanout cast...'))
    _add_unique_id(msg)
    pack_context(msg, context)
    with ConnectionContext(conf, connection_pool) as conn:
        conn.fanout_send(topic, rpc_common.serialize_msg(msg))
Esempio n. 46
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    def plug(self, network_id, port_id, device_name, mac_address,
             bridge=None, namespace=None, prefix=None):
        """Plugin the interface."""
        if not ip_lib.device_exists(device_name,
                                    self.root_helper,
                                    namespace=namespace):
            ip = ip_lib.IPWrapper(self.root_helper)

            # Enable agent to define the prefix
            if prefix:
                tap_name = device_name.replace(prefix, 'tap')
            else:
                tap_name = device_name.replace(self.DEV_NAME_PREFIX, 'tap')
            root_veth, ns_veth = ip.add_veth(tap_name, device_name)
            ns_veth.link.set_address(mac_address)

            if self.conf.network_device_mtu:
                root_veth.link.set_mtu(self.conf.network_device_mtu)
                ns_veth.link.set_mtu(self.conf.network_device_mtu)

            if namespace:
                namespace_obj = ip.ensure_namespace(namespace)
                namespace_obj.add_device_to_namespace(ns_veth)

            root_veth.link.set_up()
            ns_veth.link.set_up()

        else:
            LOG.warn(_("Device %s already exists"), device_name)
Esempio n. 47
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def notify(context, message):
    """Deprecated in Grizzly. Please use rpc_notifier instead."""

    LOG.deprecated(
        _("The rabbit_notifier is now deprecated."
          " Please use rpc_notifier instead."))
    rpc_notifier.notify(context, message)
Esempio n. 48
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class Timeout(RPCException):
    """Signifies that a timeout has occurred.

    This exception is raised if the rpc_response_timeout is reached while
    waiting for a response from the remote side.
    """
    message = _("Timeout while waiting on RPC response.")
Esempio n. 49
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def _safe_log(log_func, msg, msg_data):
    """Sanitizes the msg_data field before logging."""
    SANITIZE = {'set_admin_password': [('args', 'new_pass')],
                'run_instance': [('args', 'admin_password')],
                'route_message': [('args', 'message', 'args', 'method_info',
                                   'method_kwargs', 'password'),
                                  ('args', 'message', 'args', 'method_info',
                                   'method_kwargs', 'admin_password')]}

    has_method = 'method' in msg_data and msg_data['method'] in SANITIZE
    has_context_token = '_context_auth_token' in msg_data
    has_token = 'auth_token' in msg_data

    if not any([has_method, has_context_token, has_token]):
        return log_func(msg, msg_data)

    msg_data = copy.deepcopy(msg_data)

    if has_method:
        for arg in SANITIZE.get(msg_data['method'], []):
            try:
                d = msg_data
                for elem in arg[:-1]:
                    d = d[elem]
                d[arg[-1]] = '<SANITIZED>'
            except KeyError, e:
                LOG.info(_('Failed to sanitize %(item)s. Key error %(err)s'),
                         {'item': arg,
                          'err': e})
Esempio n. 50
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def serialize_remote_exception(failure_info, log_failure=True):
    """Prepares exception data to be sent over rpc.

    Failure_info should be a sys.exc_info() tuple.

    """
    tb = traceback.format_exception(*failure_info)
    failure = failure_info[1]
    if log_failure:
        LOG.error(_("Returning exception %s to caller"), unicode(failure))
        LOG.error(tb)

    kwargs = {}
    if hasattr(failure, 'kwargs'):
        kwargs = failure.kwargs

    data = {
        'class': str(failure.__class__.__name__),
        'module': str(failure.__class__.__module__),
        'message': unicode(failure),
        'tb': tb,
        'args': failure.args,
        'kwargs': kwargs
    }

    json_data = jsonutils.dumps(data)

    return json_data
Esempio n. 51
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def fanout_cast(conf, context, topic, msg, connection_pool):
    """Sends a message on a fanout exchange without waiting for a response."""
    LOG.debug(_('Making asynchronous fanout cast...'))
    _add_unique_id(msg)
    pack_context(msg, context)
    with ConnectionContext(conf, connection_pool) as conn:
        conn.fanout_send(topic, rpc_common.serialize_msg(msg))
Esempio n. 52
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    def start(self, interval, initial_delay=None):
        self._running = True
        done = event.Event()

        def _inner():
            if initial_delay:
                greenthread.sleep(initial_delay)

            try:
                while self._running:
                    start = timeutils.utcnow()
                    self.f(*self.args, **self.kw)
                    end = timeutils.utcnow()
                    if not self._running:
                        break
                    delay = interval - timeutils.delta_seconds(start, end)
                    if delay <= 0:
                        LOG.warn(
                            _('task run outlasted interval by %s sec') %
                            -delay)
                    greenthread.sleep(delay if delay > 0 else 0)
            except LoopingCallDone, e:
                self.stop()
                done.send(e.retvalue)
            except Exception:
                LOG.exception(_('in looping call'))
                done.send_exception(*sys.exc_info())
                return
Esempio n. 53
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def cast(conf, context, topic, msg, connection_pool):
    """Sends a message on a topic without waiting for a response."""
    LOG.debug(_('Making asynchronous cast on %s...'), topic)
    _add_unique_id(msg)
    pack_context(msg, context)
    with ConnectionContext(conf, connection_pool) as conn:
        conn.topic_send(topic, rpc_common.serialize_msg(msg))
Esempio n. 54
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 def run(self, key):
     if not self._ring_has(key):
         LOG.warn(
             _("No key defining hosts for topic '%s', "
               "see ringfile") % (key, ))
         return []
     host = next(self.ring0[key])
     return [(key + '.' + host, host)]
Esempio n. 55
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    def _pipe_watcher(self):
        # This will block until the write end is closed when the parent
        # dies unexpectedly
        self.readpipe.read()

        LOG.info(_('Parent process has died unexpectedly, exiting'))

        sys.exit(1)
Esempio n. 56
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 def run(self, key):
     # Assume starts with "fanout~", strip it for lookup.
     nkey = key.split('fanout~')[1:][0]
     if not self._ring_has(nkey):
         LOG.warn(
             _("No key defining hosts for topic '%s', "
               "see ringfile") % (nkey, ))
         return []
     return map(lambda x: (key + '.' + x, x), self.ring[nkey])