def delete(self):
     if self.is_building:
         raise exception.UnprocessableEntity("Instance %s is not ready." % self.id)
     LOG.debug(_("  ... deleting compute id = %s") % self.db_info.compute_instance_id)
     LOG.debug(_(" ... setting status to DELETING."))
     self.update_db(task_status=InstanceTasks.DELETING)
     task_api.API(self.context).delete_instance(self.id)

def is_enabled():
    cert_file = CONF.ssl.cert_file
    key_file = CONF.ssl.key_file
    ca_file = CONF.ssl.ca_file
    use_ssl = cert_file or key_file

    if cert_file and not os.path.exists(cert_file):
        raise RuntimeError(_("Unable to find cert_file : %s") % cert_file)

    if ca_file and not os.path.exists(ca_file):
        raise RuntimeError(_("Unable to find ca_file : %s") % ca_file)

    if key_file and not os.path.exists(key_file):
        raise RuntimeError(_("Unable to find key_file : %s") % key_file)

    if use_ssl and (not cert_file or not key_file):
        raise RuntimeError(
            _(
                "When running server in SSL mode, you must "
                "specify both a cert_file and key_file "
                "option value in your configuration file"
            )
        )

    return use_ssl

    def _load_servers_status(load_instance, context, db_items, find_server):
        ret = []
        for db in db_items:
            server = None
            try:
                #TODO(tim.simpson): Delete when we get notifications working!
                if InstanceTasks.BUILDING == db.task_status:
                    db.server_status = "BUILD"
                else:
                    try:
                        server = find_server(db.id, db.compute_instance_id)
                        db.server_status = server.status
                    except exception.ComputeInstanceNotFound:
                        db.server_status = "SHUTDOWN"  # Fake it...
                #TODO(tim.simpson): End of hack.

                #volumes = find_volumes(server.id)
                status = InstanceServiceStatus.find_by(instance_id=db.id)
                LOG.info(_("Server api_status(%s)") %
                         (status.status.api_status))
                if not status.status:  # This should never happen.
                    LOG.error(_("Server status could not be read for "
                                "instance id(%s)") % (db.id))
                    continue
            except exception.ModelNotFoundError:
                LOG.error(_("Server status could not be read for "
                            "instance id(%s)") % (db.id))
                continue
            ret.append(load_instance(context, db, status))
        return ret

 def index(self, req, tenant_id, detailed=False):
     """Return all hosts."""
     LOG.info(_("req : '%s'\n\n") % req)
     LOG.info(_("Indexing a host for tenant '%s'") % tenant_id)
     context = req.environ[wsgi.CONTEXT_KEY]
     hosts = models.SimpleHost.load_all(context)
     return wsgi.Result(views.HostsView(hosts).data(), 200)

    def action(self, req, body, tenant_id, id):
        LOG.info("req : '%s'\n\n" % req)
        LOG.info("Comitting an ACTION again instance %s for tenant '%s'"
                 % (id, tenant_id))
        if not body:
            raise exception.BadRequest(_("Invalid request body."))
        context = req.environ[wsgi.CONTEXT_KEY]
        instance = models.Instance.load(context, id)
        _actions = {
            'restart': self._action_restart,
            'resize': self._action_resize,
            'reset_password': self._action_reset_password
        }
        selected_action = None
        for key in body:
            if key in _actions:
                if selected_action is not None:
                    msg = _("Only one action can be specified per request.")
                    raise exception.BadRequest(msg)
                selected_action = _actions[key]
            else:
                msg = _("Invalid instance action: %s") % key
                raise exception.BadRequest(msg)

        if selected_action:
            return selected_action(instance, body)
        else:
            raise exception.BadRequest(_("Invalid request body."))

        def inner(*args, **kwargs):
            # NOTE(soren): If we ever go natively threaded, this will be racy.
            #              See http://stackoverflow.com/questions/5390569/dyn
            #              amically-allocating-and-destroying-mutexes
            sem = _semaphores.get(name, semaphore.Semaphore())
            if name not in _semaphores:
                # this check is not racy - we're already holding ref locally
                # so GC won't remove the item and there was no IO switch
                # (only valid in greenthreads)
                _semaphores[name] = sem

            with sem:
                LOG.debug(_('Got semaphore "%(lock)s" for method '
                            '"%(method)s"...'), {'lock': name,
                                                 'method': f.__name__})
                if external and not CONF.disable_process_locking:
                    LOG.debug(_('Attempting to grab file lock "%(lock)s" for '
                                'method "%(method)s"...'),
                              {'lock': name, 'method': f.__name__})
                    cleanup_dir = False

                    # We need a copy of lock_path because it is non-local
                    local_lock_path = lock_path
                    if not local_lock_path:
                        local_lock_path = CONF.lock_path

                    if not local_lock_path:
                        cleanup_dir = True
                        local_lock_path = tempfile.mkdtemp()

                    if not os.path.exists(local_lock_path):
                        cleanup_dir = True
                        fileutils.ensure_tree(local_lock_path)

                    # NOTE(mikal): the lock name cannot contain directory
                    # separators
                    safe_name = name.replace(os.sep, '_')
                    lock_file_name = '%s%s' % (lock_file_prefix, safe_name)
                    lock_file_path = os.path.join(local_lock_path,
                                                  lock_file_name)

                    try:
                        lock = InterProcessLock(lock_file_path)
                        with lock:
                            LOG.debug(_('Got file lock "%(lock)s" at %(path)s '
                                        'for method "%(method)s"...'),
                                      {'lock': name,
                                       'path': lock_file_path,
                                       'method': f.__name__})
                            retval = f(*args, **kwargs)
                    finally:
                        # NOTE(vish): This removes the tempdir if we needed
                        #             to create one. This is used to cleanup
                        #             the locks left behind by unit tests.
                        if cleanup_dir:
                            shutil.rmtree(local_lock_path)
                else:
                    retval = f(*args, **kwargs)

            return retval

    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

    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)

    def __init__(self, addr, zmq_type, bind=True, subscribe=None):
        self.sock = ZMQ_CTX.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."))

    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()

    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)

            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})

 def _error_callback(exc):
     if isinstance(exc, socket.timeout):
         LOG.exception(_("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

 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.close()
         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)

    def _process_data(self, ctxt, version, method, namespace, 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, namespace,
                                       **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)

    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"))

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

    def create_consumer(self, topic, proxy, fanout=False):
        # Only consume on the base topic name.
        topic = topic.split('.', 1)[0]

        LOG.info(_("Create Consumer for topic (%(topic)s)") %
                 {'topic': topic})

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

        # 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)

    def start_mysql(self, update_db=False):
        LOG.info(_("Starting mysql..."))
        # This is the site of all the trouble in the restart tests.
        # Essentially what happens is that mysql start fails, but does not
        # die. It is then impossible to kill the original, so

        self._enable_mysql_on_boot()

        try:
            utils.execute_with_timeout("sudo", "/etc/init.d/mysql", "start")
        except exception.ProcessExecutionError:
            # it seems mysql (percona, at least) might come back with [Fail]
            # but actually come up ok. we're looking into the timing issue on
            # parallel, but for now, we'd like to give it one more chance to
            # come up. so regardless of the execute_with_timeout() respose,
            # we'll assume mysql comes up and check it's status for a while.
            pass
        if not self.status.wait_for_real_status_to_change_to(
                rd_models.ServiceStatuses.RUNNING,
                self.state_change_wait_time, update_db):
            LOG.error(_("Start up of MySQL failed!"))
            # If it won't start, but won't die either, kill it by hand so we
            # don't let a rouge process wander around.
            try:
                utils.execute_with_timeout("sudo", "pkill", "-9", "mysql")
            except exception.ProcessExecutionError, p:
                LOG.error("Error killing stalled mysql start command.")
                LOG.error(p)
            # There's nothing more we can do...
            self.status.end_install_or_restart()
            raise RuntimeError("Could not start MySQL!")

def _multi_send(method, context, topic, msg, timeout=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 = 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, _topic, msg, timeout)
            return
        return method(_addr, context, _topic, _topic, msg, timeout)