Exemplo n.º 1
0
    def _mock_api_server(napp):
        """Instantiate APIServer, mock ``.app`` and start ``napp`` API."""
        server = APIServer('test')
        server.app = Mock()  # Flask app
        server.app.url_map.iter_rules.return_value = []

        server.register_napp_endpoints(napp)
        return server
Exemplo n.º 2
0
 def setUp(self):
     """Instantiate a APIServer."""
     self.api_server = APIServer('CustomName', False)
     self.napps_manager = MagicMock()
     self.api_server.server = MagicMock()
     self.api_server.napps_manager = self.napps_manager
     self.api_server.napps_dir = 'napps_dir'
     self.api_server.flask_dir = 'flask_dir'
Exemplo n.º 3
0
class TestAPIServer(unittest.TestCase):
    """Test the class APIServer."""
    def setUp(self):
        """Instantiate a APIServer."""
        self.api_server = APIServer('CustomName', False)

    def test_deprecation_warning(self):
        """Deprecated method should suggest @rest decorator."""
        with warnings.catch_warnings(record=True) as wrngs:
            warnings.simplefilter("always")  # trigger all warnings
            self.api_server.register_rest_endpoint('rule', lambda x: x,
                                                   ['POST'])
            self.assertEqual(1, len(wrngs))
            warning = wrngs[0]
            self.assertEqual(warning.category, DeprecationWarning)
            self.assertIn('@rest', str(warning.message))

    @staticmethod
    def __custom_endpoint():
        """Custom method used by APIServer."""
        return "Custom Endpoint"
Exemplo n.º 4
0
class TestAPIServer(unittest.TestCase):
    """Test the class APIServer."""

    def setUp(self):
        """Instantiate a APIServer."""
        self.api_server = APIServer('CustomName', False)

    def test_register_rest_endpoint(self):
        """Test whether register_rest_endpoint is registering an endpoint."""
        self.api_server.register_rest_endpoint('/custom_method/',
                                               self.__custom_endpoint,
                                               methods=['GET'])

        expected_endpoint = '/kytos/custom_method/'
        actual_endpoints = self.api_server.rest_endpoints
        self.assertIn(expected_endpoint, actual_endpoints)

    def test_register_api_server_routes(self):
        """Server routes should include status and shutdown endpoints."""
        self.api_server.register_api_server_routes()

        expecteds = ['/kytos/status/', '/kytos/shutdown/',
                     '/static/<path:filename>']

        actual_endpoints = self.api_server.rest_endpoints

        self.assertListEqual(sorted(expecteds), sorted(actual_endpoints))

    def test_rest_endpoints(self):
        """Test whether rest_endpoint returns all registered endpoints."""
        endpoints = ['/custom/', '/custom_2/', '/custom_3/']

        for endpoint in endpoints:
            self.api_server.register_rest_endpoint(endpoint,
                                                   self.__custom_endpoint,
                                                   methods=['GET'])

        expected_endpoints = ['/kytos{}'.format(e) for e in endpoints]
        expected_endpoints.append('/static/<path:filename>')

        actual_endpoints = self.api_server.rest_endpoints
        self.assertListEqual(sorted(expected_endpoints),
                             sorted(actual_endpoints))

    @staticmethod
    def __custom_endpoint():
        """Custom method used by APIServer."""
        return "Custom Endpoint"
Exemplo n.º 5
0
    def __init__(self, options=None, loop=None):
        """Init method of Controller class takes the parameters below.

        Args:
            options (:attr:`ParseArgs.args`): :attr:`options` attribute from an
                instance of :class:`~kytos.core.config.KytosConfig` class.
        """
        if options is None:
            options = KytosConfig().options['daemon']

        self._loop = loop or asyncio.get_event_loop()
        self._pool = ThreadPoolExecutor(max_workers=1)

        # asyncio tasks
        self._tasks = []

        #: dict: keep the main threads of the controller (buffers and handler)
        self._threads = {}
        #: KytosBuffers: KytosBuffer object with Controller buffers
        self.buffers = KytosBuffers(loop=self._loop)
        #: dict: keep track of the socket connections labeled by ``(ip, port)``
        #:
        #: This dict stores all connections between the controller and the
        #: switches. The key for this dict is a tuple (ip, port). The content
        #: is a Connection
        self.connections = {}
        #: dict: mapping of events and event listeners.
        #:
        #: The key of the dict is a KytosEvent (or a string that represent a
        #: regex to match against KytosEvents) and the value is a list of
        #: methods that will receive the referenced event
        self.events_listeners = {
            'kytos/core.connection.new': [self.new_connection]
        }

        #: dict: Current loaded apps - ``'napp_name'``: ``napp`` (instance)
        #:
        #: The key is the napp name (string), while the value is the napp
        #: instance itself.
        self.napps = {}
        #: Object generated by ParseArgs on config.py file
        self.options = options
        #: KytosServer: Instance of KytosServer that will be listening to TCP
        #: connections.
        self.server = None
        #: dict: Current existing switches.
        #:
        #: The key is the switch dpid, while the value is a Switch object.
        self.switches = {}  # dpid: Switch()
        self._switches_lock = threading.Lock()

        #: datetime.datetime: Time when the controller finished starting.
        self.started_at = None

        #: logging.Logger: Logger instance used by Kytos.
        self.log = None

        #: Observer that handle NApps when they are enabled or disabled.
        self.napp_dir_listener = NAppDirListener(self)

        self.napps_manager = NAppsManager(self)

        #: API Server used to expose rest endpoints.
        self.api_server = APIServer(__name__, self.options.listen,
                                    self.options.api_port, self.napps_manager,
                                    self.options.napps)

        self.auth = Auth(self)
        self.dead_letter = DeadLetter(self)

        self._register_endpoints()
        #: Adding the napps 'enabled' directory into the PATH
        #: Now you can access the enabled napps with:
        #: from napps.<username>.<napp_name> import ?....
        sys.path.append(os.path.join(self.options.napps, os.pardir))
        sys.excepthook = exc_handler
Exemplo n.º 6
0
class Controller:
    """Main class of Kytos.

    The main responsibilities of this class are:
        - start a thread with :class:`~.core.tcp_server.KytosServer`;
        - manage KytosNApps (install, load and unload);
        - keep the buffers (instance of :class:`~.core.buffers.KytosBuffers`);
        - manage which event should be sent to NApps methods;
        - manage the buffers handlers, considering one thread per handler.
    """

    # Created issue #568 for the disabled checks.
    # pylint: disable=too-many-instance-attributes,too-many-public-methods
    def __init__(self, options=None, loop=None):
        """Init method of Controller class takes the parameters below.

        Args:
            options (:attr:`ParseArgs.args`): :attr:`options` attribute from an
                instance of :class:`~kytos.core.config.KytosConfig` class.
        """
        if options is None:
            options = KytosConfig().options['daemon']

        self._loop = loop or asyncio.get_event_loop()
        self._pool = ThreadPoolExecutor(max_workers=1)

        # asyncio tasks
        self._tasks = []

        #: dict: keep the main threads of the controller (buffers and handler)
        self._threads = {}
        #: KytosBuffers: KytosBuffer object with Controller buffers
        self.buffers = KytosBuffers(loop=self._loop)
        #: dict: keep track of the socket connections labeled by ``(ip, port)``
        #:
        #: This dict stores all connections between the controller and the
        #: switches. The key for this dict is a tuple (ip, port). The content
        #: is a Connection
        self.connections = {}
        #: dict: mapping of events and event listeners.
        #:
        #: The key of the dict is a KytosEvent (or a string that represent a
        #: regex to match against KytosEvents) and the value is a list of
        #: methods that will receive the referenced event
        self.events_listeners = {
            'kytos/core.connection.new': [self.new_connection]
        }

        #: dict: Current loaded apps - ``'napp_name'``: ``napp`` (instance)
        #:
        #: The key is the napp name (string), while the value is the napp
        #: instance itself.
        self.napps = {}
        #: Object generated by ParseArgs on config.py file
        self.options = options
        #: KytosServer: Instance of KytosServer that will be listening to TCP
        #: connections.
        self.server = None
        #: dict: Current existing switches.
        #:
        #: The key is the switch dpid, while the value is a Switch object.
        self.switches = {}  # dpid: Switch()
        self._switches_lock = threading.Lock()

        #: datetime.datetime: Time when the controller finished starting.
        self.started_at = None

        #: logging.Logger: Logger instance used by Kytos.
        self.log = None

        #: Observer that handle NApps when they are enabled or disabled.
        self.napp_dir_listener = NAppDirListener(self)

        self.napps_manager = NAppsManager(self)

        #: API Server used to expose rest endpoints.
        self.api_server = APIServer(__name__, self.options.listen,
                                    self.options.api_port, self.napps_manager,
                                    self.options.napps)

        self.auth = Auth(self)
        self.dead_letter = DeadLetter(self)

        self._register_endpoints()
        #: Adding the napps 'enabled' directory into the PATH
        #: Now you can access the enabled napps with:
        #: from napps.<username>.<napp_name> import ?....
        sys.path.append(os.path.join(self.options.napps, os.pardir))
        sys.excepthook = exc_handler

    def enable_logs(self):
        """Register kytos log and enable the logs."""
        LogManager.load_config_file(self.options.logging, self.options.debug)
        LogManager.enable_websocket(self.api_server.server)
        self.log = logging.getLogger(__name__)

    @staticmethod
    def loggers():
        """List all logging Loggers.

        Return a list of Logger objects, with name and logging level.
        """
        return [
            logging.getLogger(name) for name in logging.root.manager.loggerDict
            if "kytos" in name
        ]

    def toggle_debug(self, name=None):
        """Enable/disable logging debug messages to a given logger name.

        If the name parameter is not specified the debug will be
        enabled/disabled following the initial config file. It will decide
        to enable/disable using the 'kytos' name to find the current
        logger level.
        Obs: To disable the debug the logging will be set to NOTSET

        Args:
            name(text): Full hierarchy Logger name. Ex: "kytos.core.controller"
        """
        if name and name not in logging.root.manager.loggerDict:
            # A Logger name that is not declared in logging will raise an error
            # otherwise logging would create a new Logger.
            raise ValueError(f"Invalid logger name: {name}")

        if not name:
            # Logger name not specified.
            level = logging.getLogger('kytos').getEffectiveLevel()
            enable_debug = level != logging.DEBUG

            # Enable/disable default Loggers
            LogManager.load_config_file(self.options.logging, enable_debug)
            return

        # Get effective logger level for the name
        level = logging.getLogger(name).getEffectiveLevel()
        logger = logging.getLogger(name)

        if level == logging.DEBUG:
            # disable debug
            logger.setLevel(logging.NOTSET)
        else:
            # enable debug
            logger.setLevel(logging.DEBUG)

    def start(self, restart=False):
        """Create pidfile and call start_controller method."""
        self.enable_logs()
        if self.options.database:
            self.db_conn_or_core_shutdown()
        if self.options.apm:
            self.init_apm_or_core_shutdown()
        if not restart:
            self.create_pidfile()
        self.start_controller()

    def create_pidfile(self):
        """Create a pidfile."""
        pid = os.getpid()

        # Creates directory if it doesn't exist
        # System can erase /var/run's content
        pid_folder = Path(self.options.pidfile).parent
        self.log.info(pid_folder)

        # Pylint incorrectly infers Path objects
        # https://github.com/PyCQA/pylint/issues/224
        # pylint: disable=no-member
        if not pid_folder.exists():
            pid_folder.mkdir()
            pid_folder.chmod(0o1777)
        # pylint: enable=no-member

        # Make sure the file is deleted when controller stops
        atexit.register(Path(self.options.pidfile).unlink)

        # Checks if a pidfile exists. Creates a new file.
        try:
            pidfile = open(self.options.pidfile, mode='x')
        except OSError:
            # This happens if there is a pidfile already.
            # We shall check if the process that created the pidfile is still
            # running.
            try:
                existing_file = open(self.options.pidfile, mode='r')
                old_pid = int(existing_file.read())
                os.kill(old_pid, 0)
                # If kill() doesn't return an error, there's a process running
                # with the same PID. We assume it is Kytos and quit.
                # Otherwise, overwrite the file and proceed.
                error_msg = ("PID file {} exists. Delete it if Kytos is not "
                             "running. Aborting.")
                sys.exit(error_msg.format(self.options.pidfile))
            except OSError:
                try:
                    pidfile = open(self.options.pidfile, mode='w')
                except OSError as exception:
                    error_msg = "Failed to create pidfile {}: {}."
                    sys.exit(error_msg.format(self.options.pidfile, exception))

        # Identifies the process that created the pidfile.
        pidfile.write(str(pid))
        pidfile.close()

    def start_controller(self):
        """Start the controller.

        Starts the KytosServer (TCP Server) coroutine.
        Starts a thread for each buffer handler.
        Load the installed apps.
        """
        self.log.info("Starting Kytos - Kytos Controller")
        self.server = KytosServer(
            (self.options.listen, int(self.options.port)), KytosServerProtocol,
            self, self.options.protocol_name)

        self.log.info("Starting TCP server: %s", self.server)
        self.server.serve_forever()

        def _stop_loop(_):
            loop = asyncio.get_event_loop()
            # print(_.result())
            threads = threading.enumerate()
            self.log.debug("%s threads before loop.stop: %s", len(threads),
                           threads)
            loop.stop()

        async def _run_api_server_thread(executor):
            log = logging.getLogger('kytos.core.controller.api_server_thread')
            log.debug('starting')
            # log.debug('creating tasks')
            loop = asyncio.get_event_loop()
            blocking_tasks = [
                loop.run_in_executor(executor, self.api_server.run)
            ]
            # log.debug('waiting for tasks')
            completed, pending = await asyncio.wait(blocking_tasks)
            # results = [t.result() for t in completed]
            # log.debug('results: {!r}'.format(results))
            log.debug('completed: %d, pending: %d', len(completed),
                      len(pending))

        task = self._loop.create_task(self.raw_event_handler())
        self._tasks.append(task)
        task = self._loop.create_task(self.msg_in_event_handler())
        self._tasks.append(task)
        task = self._loop.create_task(self.msg_out_event_handler())
        self._tasks.append(task)
        task = self._loop.create_task(self.app_event_handler())
        self._tasks.append(task)
        task = self._loop.create_task(_run_api_server_thread(self._pool))
        task.add_done_callback(_stop_loop)
        self._tasks.append(task)

        self.log.info("ThreadPool started: %s", self._pool)

        # ASYNC TODO: ensure all threads started correctly
        # This is critical, if any of them failed starting we should exit.
        # sys.exit(error_msg.format(thread, exception))

        self.log.info("Loading Kytos NApps...")
        self.napp_dir_listener.start()
        self.pre_install_napps(self.options.napps_pre_installed)
        self.load_napps()

        self.started_at = now()

    def db_conn_or_core_shutdown(self):
        """Ensure db connection or core shutdown."""
        try:
            db_conn_wait(db_backend=self.options.database)
        except KytosDBInitException as exc:
            sys.exit(f"Kytos couldn't start because of {str(exc)}")

    def init_apm_or_core_shutdown(self, **kwargs):
        """Init APM instrumentation or core shutdown."""
        if not self.options.apm:
            return
        try:
            init_apm(self.options.apm, app=self.api_server.app, **kwargs)
        except KytosAPMInitException as exc:
            sys.exit(f"Kytos couldn't start because of {str(exc)}")

    def _register_endpoints(self):
        """Register all rest endpoint served by kytos.

        -   Register APIServer endpoints
        -   Register WebUI endpoints
        -   Register ``/api/kytos/core/config`` endpoint
        """
        self.api_server.start_api()
        # Register controller endpoints as /api/kytos/core/...
        self.api_server.register_core_endpoint('config/',
                                               self.configuration_endpoint)
        self.api_server.register_core_endpoint('metadata/',
                                               Controller.metadata_endpoint)
        self.api_server.register_core_endpoint(
            'reload/<username>/<napp_name>/', self.rest_reload_napp)
        self.api_server.register_core_endpoint('reload/all',
                                               self.rest_reload_all_napps)
        self.auth.register_core_auth_services()
        self.dead_letter.register_endpoints()

    def register_rest_endpoint(self, url, function, methods):
        """Deprecate in favor of @rest decorator."""
        self.api_server.register_rest_endpoint(url, function, methods)

    @classmethod
    def metadata_endpoint(cls):
        """Return the Kytos metadata.

        Returns:
            string: Json with current kytos metadata.

        """
        meta_path = "%s/metadata.py" % os.path.dirname(__file__)
        meta_file = open(meta_path).read()
        metadata = dict(re.findall(r"(__[a-z]+__)\s*=\s*'([^']+)'", meta_file))
        return json.dumps(metadata)

    def configuration_endpoint(self):
        """Return the configuration options used by Kytos.

        Returns:
            string: Json with current configurations used by kytos.

        """
        return json.dumps(self.options.__dict__)

    def restart(self, graceful=True):
        """Restart Kytos SDN Controller.

        Args:
            graceful(bool): Represents the way that Kytos will restart.
        """
        if self.started_at is not None:
            self.stop(graceful)
            self.__init__(self.options)

        self.start(restart=True)

    def stop(self, graceful=True):
        """Shutdown all services used by kytos.

        This method should:
            - stop all Websockets
            - stop the API Server
            - stop the Controller
        """
        if self.started_at:
            self.stop_controller(graceful)

    def stop_controller(self, graceful=True):
        """Stop the controller.

        This method should:
            - announce on the network that the controller will shutdown;
            - stop receiving incoming packages;
            - call the 'shutdown' method of each KytosNApp that is running;
            - finish reading the events on all buffers;
            - stop each running handler;
            - stop all running threads;
            - stop the KytosServer;
        """
        self.log.info("Stopping Kytos")

        self.buffers.send_stop_signal()
        self.api_server.stop_api_server()
        self.napp_dir_listener.stop()

        self.log.info("Stopping threadpool: %s", self._pool)
        for pool_name in executors:
            self.log.info("Stopping threadpool: %s", pool_name)

        threads = threading.enumerate()
        self.log.debug("%s threads before threadpool shutdown: %s",
                       len(threads), threads)

        try:
            # Python >= 3.9
            # pylint: disable=unexpected-keyword-arg
            self._pool.shutdown(wait=graceful, cancel_futures=True)
            for executor_pool in executors.values():
                executor_pool.shutdown(wait=graceful, cancel_futures=True)
        except TypeError:
            self._pool.shutdown(wait=graceful)
            for executor_pool in executors.values():
                executor_pool.shutdown(wait=graceful)

        # self.server.socket.shutdown()
        # self.server.socket.close()

        # for thread in self._threads.values():
        #     self.log.info("Stopping thread: %s", thread.name)
        #     thread.join()

        # for thread in self._threads.values():
        #     while thread.is_alive():
        #         self.log.info("Thread is alive: %s", thread.name)
        #         pass

        self.started_at = None
        self.unload_napps()
        self.buffers = KytosBuffers()

        # Cancel all async tasks (event handlers and servers)
        for task in self._tasks:
            task.cancel()

        # ASYNC TODO: close connections
        # self.server.server_close()

        # Shutdown the TCP server and the main asyncio loop
        self.server.shutdown()

    def status(self):
        """Return status of Kytos Server.

        If the controller kytos is running this method will be returned
        "Running since 'Started_At'", otherwise "Stopped".

        Returns:
            string: String with kytos status.

        """
        if self.started_at:
            return "Running since %s" % self.started_at
        return "Stopped"

    def uptime(self):
        """Return the uptime of kytos server.

        This method should return:
            - 0 if Kytos Server is stopped.
            - (kytos.start_at - datetime.now) if Kytos Server is running.

        Returns:
           datetime.timedelta: The uptime interval.

        """
        return now() - self.started_at if self.started_at else 0

    def notify_listeners(self, event):
        """Send the event to the specified listeners.

        Loops over self.events_listeners matching (by regexp) the attribute
        name of the event with the keys of events_listeners. If a match occurs,
        then send the event to each registered listener.

        Args:
            event (~kytos.core.KytosEvent): An instance of a KytosEvent.
        """
        self.log.debug("looking for listeners for %s", event)
        for event_regex, listeners in dict(self.events_listeners).items():
            # self.log.debug("listeners found for %s: %r => %s", event,
            #                event_regex, [l.__qualname__ for l in listeners])
            # Do not match if the event has more characters
            # e.g. "shutdown" won't match "shutdown.kytos/of_core"
            if event_regex[-1] != '$' or event_regex[-2] == '\\':
                event_regex += '$'
            if re.match(event_regex, event.name):
                # self.log.debug('Calling listeners for %s', event)
                for listener in listeners:
                    listener(event)

    async def raw_event_handler(self):
        """Handle raw events.

        Listen to the raw_buffer and send all its events to the
        corresponding listeners.
        """
        self.log.info("Raw Event Handler started")
        while True:
            event = await self.buffers.raw.aget()
            self.notify_listeners(event)
            self.log.debug("Raw Event handler called")

            if event.name == "kytos/core.shutdown":
                self.log.debug("Raw Event handler stopped")
                break

    async def msg_in_event_handler(self):
        """Handle msg_in events.

        Listen to the msg_in buffer and send all its events to the
        corresponding listeners.
        """
        self.log.info("Message In Event Handler started")
        while True:
            event = await self.buffers.msg_in.aget()
            self.notify_listeners(event)
            self.log.debug("Message In Event handler called")

            if event.name == "kytos/core.shutdown":
                self.log.debug("Message In Event handler stopped")
                break

    async def publish_connection_error(self, event):
        """Publish connection error event.

        Args:
            event (KytosEvent): Event that triggered for error propagation.
        """
        event.name = \
            f"kytos/core.{event.destination.protocol.name}.connection.error"
        error_msg = f"Connection state: {event.destination.state}"
        event.content["exception"] = error_msg
        await self.buffers.app.aput(event)

    async def msg_out_event_handler(self):
        """Handle msg_out events.

        Listen to the msg_out buffer and send all its events to the
        corresponding listeners.
        """
        self.log.info("Message Out Event Handler started")
        while True:
            triggered_event = await self.buffers.msg_out.aget()

            if triggered_event.name == "kytos/core.shutdown":
                self.log.debug("Message Out Event handler stopped")
                break

            message = triggered_event.content['message']
            destination = triggered_event.destination
            try:
                if (destination
                        and not destination.state == ConnectionState.FINISHED):
                    packet = message.pack()
                    destination.send(packet)
                    self.log.debug(
                        'Connection %s: OUT OFP, '
                        'version: %s, type: %s, xid: %s - %s', destination.id,
                        message.header.version, message.header.message_type,
                        message.header.xid, packet.hex())
                    self.notify_listeners(triggered_event)
                    self.log.debug("Message Out Event handler called")
                    continue

            except (OSError, SocketError):
                pass

            await self.publish_connection_error(triggered_event)
            self.log.info("connection closed. Cannot send message")

    async def app_event_handler(self):
        """Handle app events.

        Listen to the app buffer and send all its events to the
        corresponding listeners.
        """
        self.log.info("App Event Handler started")
        while True:
            event = await self.buffers.app.aget()
            self.notify_listeners(event)
            self.log.debug("App Event handler called")

            if event.name == "kytos/core.shutdown":
                self.log.debug("App Event handler stopped")
                break

    def get_interface_by_id(self, interface_id):
        """Find a Interface  with interface_id.

        Args:
            interface_id(str): Interface Identifier.

        Returns:
            Interface: Instance of Interface with the id given.

        """
        if interface_id is None:
            return None

        switch_id = ":".join(interface_id.split(":")[:-1])
        interface_number = int(interface_id.split(":")[-1])

        switch = self.switches.get(switch_id)

        if not switch:
            return None

        return switch.interfaces.get(interface_number, None)

    def get_switch_by_dpid(self, dpid):
        """Return a specific switch by dpid.

        Args:
            dpid (|DPID|): dpid object used to identify a switch.

        Returns:
            :class:`~kytos.core.switch.Switch`: Switch with dpid specified.

        """
        return self.switches.get(dpid)

    def get_switch_or_create(self, dpid, connection=None):
        """Return switch or create it if necessary.

        Args:
            dpid (|DPID|): dpid object used to identify a switch.
            connection (:class:`~kytos.core.connection.Connection`):
                connection used by switch. If a switch has a connection that
                will be updated.

        Returns:
            :class:`~kytos.core.switch.Switch`: new or existent switch.

        """
        with self._switches_lock:
            if connection:
                self.create_or_update_connection(connection)

            switch = self.get_switch_by_dpid(dpid)
            event_name = 'kytos/core.switch.'

            if switch is None:
                switch = Switch(dpid=dpid)
                self.add_new_switch(switch)
                event_name += 'new'
            else:
                event_name += 'reconnected'

            self.set_switch_options(dpid=dpid)
            event = KytosEvent(name=event_name, content={'switch': switch})

            if connection:
                old_connection = switch.connection
                switch.update_connection(connection)

                if old_connection is not connection:
                    self.remove_connection(old_connection)

            self.buffers.app.put(event)

            return switch

    def set_switch_options(self, dpid):
        """Update the switch settings based on kytos.conf options.

        Args:
            dpid (str): dpid used to identify a switch.

        """
        switch = self.switches.get(dpid)
        if not switch:
            return

        vlan_pool = {}
        vlan_pool = self.options.vlan_pool
        if not vlan_pool:
            return

        if vlan_pool.get(dpid):
            self.log.info("Loading vlan_pool configuration for dpid %s", dpid)
            for intf_num, port_list in vlan_pool[dpid].items():
                if not switch.interfaces.get((intf_num)):
                    vlan_ids = set()
                    for vlan_range in port_list:
                        (vlan_begin, vlan_end) = (vlan_range[0:2])
                        for vlan_id in range(vlan_begin, vlan_end):
                            vlan_ids.add(vlan_id)
                    intf_num = int(intf_num)
                    intf = Interface(name=intf_num,
                                     port_number=intf_num,
                                     switch=switch)
                    intf.set_available_tags(vlan_ids)
                    switch.update_interface(intf)

    def create_or_update_connection(self, connection):
        """Update a connection.

        Args:
            connection (:class:`~kytos.core.connection.Connection`):
                Instance of connection that will be updated.
        """
        self.connections[connection.id] = connection

    def get_connection_by_id(self, conn_id):
        """Return a existent connection by id.

        Args:
            id (int): id from a connection.

        Returns:
            :class:`~kytos.core.connection.Connection`: Instance of connection
                or None Type.

        """
        return self.connections.get(conn_id)

    def remove_connection(self, connection):
        """Close a existent connection and remove it.

        Args:
            connection (:class:`~kytos.core.connection.Connection`):
                Instance of connection that will be removed.
        """
        if connection is None:
            return False

        try:
            connection.close()
            del self.connections[connection.id]
        except KeyError:
            return False
        return True

    def remove_switch(self, switch):
        """Remove an existent switch.

        Args:
            switch (:class:`~kytos.core.switch.Switch`):
                Instance of switch that will be removed.
        """
        try:
            del self.switches[switch.dpid]
        except KeyError:
            return False
        return True

    def new_connection(self, event):
        """Handle a kytos/core.connection.new event.

        This method will read new connection event and store the connection
        (socket) into the connections attribute on the controller.

        It also clear all references to the connection since it is a new
        connection on the same ip:port.

        Args:
            event (~kytos.core.KytosEvent):
                The received event (``kytos/core.connection.new``) with the
                needed info.
        """
        self.log.info("Handling %s...", event)

        connection = event.source
        self.log.debug("Event source: %s", event.source)

        # Remove old connection (aka cleanup) if it exists
        if self.get_connection_by_id(connection.id):
            self.remove_connection(connection.id)

        # Update connections with the new connection
        self.create_or_update_connection(connection)

    def add_new_switch(self, switch):
        """Add a new switch on the controller.

        Args:
            switch (Switch): A Switch object
        """
        self.switches[switch.dpid] = switch

    def _import_napp(self, username, napp_name):
        """Import a NApp module.

        Raises:
            FileNotFoundError: if NApp's main.py is not found.
            ModuleNotFoundError: if any NApp requirement is not installed.

        """
        mod_name = '.'.join(['napps', username, napp_name, 'main'])
        path = os.path.join(self.options.napps, username, napp_name, 'main.py')
        napp_spec = spec_from_file_location(mod_name, path)
        napp_module = module_from_spec(napp_spec)
        sys.modules[napp_spec.name] = napp_module
        napp_spec.loader.exec_module(napp_module)
        return napp_module

    def load_napp(self, username, napp_name):
        """Load a single NApp.

        Args:
            username (str): NApp username (makes up NApp's path).
            napp_name (str): Name of the NApp to be loaded.
        """
        if (username, napp_name) in self.napps:
            message = 'NApp %s/%s was already loaded'
            self.log.warning(message, username, napp_name)
            return

        try:
            napp_module = self._import_napp(username, napp_name)
        except ModuleNotFoundError as err:
            self.log.error("Error loading NApp '%s/%s': %s", username,
                           napp_name, err)
            return
        except FileNotFoundError as err:
            msg = "NApp module not found, assuming it's a meta-napp: %s"
            self.log.warning(msg, err.filename)
            return

        try:
            napp = napp_module.Main(controller=self)
        except:  # noqa pylint: disable=bare-except
            self.log.critical("NApp initialization failed: %s/%s",
                              username,
                              napp_name,
                              exc_info=True)
            return

        self.napps[(username, napp_name)] = napp

        napp.start()
        self.api_server.authenticate_endpoints(napp)
        self.api_server.register_napp_endpoints(napp)

        # pylint: disable=protected-access
        for event, listeners in napp._listeners.items():
            self.events_listeners.setdefault(event, []).extend(listeners)
        # pylint: enable=protected-access

    def pre_install_napps(self, napps, enable=True):
        """Pre install and enable NApps.

        Before installing, it'll check if it's installed yet.

        Args:
            napps ([str]): List of NApps to be pre-installed and enabled.
        """
        all_napps = self.napps_manager.get_installed_napps()
        installed = [str(napp) for napp in all_napps]
        napps_diff = [napp for napp in napps if napp not in installed]
        for napp in napps_diff:
            self.napps_manager.install(napp, enable=enable)

    def load_napps(self):
        """Load all NApps enabled on the NApps dir."""
        for napp in self.napps_manager.get_enabled_napps():
            try:
                self.log.info("Loading NApp %s", napp.id)
                self.load_napp(napp.username, napp.name)
            except FileNotFoundError as exception:
                self.log.error("Could not load NApp %s: %s", napp.id,
                               exception)

    def unload_napp(self, username, napp_name):
        """Unload a specific NApp.

        Args:
            username (str): NApp username.
            napp_name (str): Name of the NApp to be unloaded.
        """
        napp = self.napps.pop((username, napp_name), None)

        if napp is None:
            self.log.warning('NApp %s/%s was not loaded', username, napp_name)
        else:
            self.log.info("Shutting down NApp %s/%s...", username, napp_name)
            napp_id = NApp(username, napp_name).id
            event = KytosEvent(name='kytos/core.shutdown.' + napp_id)
            napp_shutdown_fn = self.events_listeners[event.name][0]
            # Call listener before removing it from events_listeners
            napp_shutdown_fn(event)

            # Remove rest endpoints from that napp
            self.api_server.remove_napp_endpoints(napp)

            # Removing listeners from that napp
            # pylint: disable=protected-access
            for event_type, napp_listeners in napp._listeners.items():
                event_listeners = self.events_listeners[event_type]
                for listener in napp_listeners:
                    event_listeners.remove(listener)
                if not event_listeners:
                    del self.events_listeners[event_type]
            # pylint: enable=protected-access

    def unload_napps(self):
        """Unload all loaded NApps that are not core NApps."""
        # list() is used here to avoid the error:
        # 'RuntimeError: dictionary changed size during iteration'
        # This is caused by looping over an dictionary while removing
        # items from it.
        for (username, napp_name) in list(self.napps.keys()):  # noqa
            self.unload_napp(username, napp_name)

    def reload_napp_module(self, username, napp_name, napp_file):
        """Reload a NApp Module."""
        mod_name = '.'.join(['napps', username, napp_name, napp_file])
        try:
            napp_module = import_module(mod_name)
        except ModuleNotFoundError:
            self.log.error("Module '%s' not found", mod_name)
            raise
        try:
            napp_module = reload_module(napp_module)
        except ImportError as err:
            self.log.error("Error reloading NApp '%s/%s': %s", username,
                           napp_name, err)
            raise

    def reload_napp(self, username, napp_name):
        """Reload a NApp."""
        self.unload_napp(username, napp_name)
        try:
            self.reload_napp_module(username, napp_name, 'settings')
            self.reload_napp_module(username, napp_name, 'main')
        except (ModuleNotFoundError, ImportError):
            return 400
        self.log.info("NApp '%s/%s' successfully reloaded", username,
                      napp_name)
        self.load_napp(username, napp_name)
        return 200

    def rest_reload_napp(self, username, napp_name):
        """Request reload a NApp."""
        res = self.reload_napp(username, napp_name)
        return 'reloaded', res

    def rest_reload_all_napps(self):
        """Request reload all NApps."""
        for napp in self.napps:
            self.reload_napp(*napp)
        return 'reloaded', 200
Exemplo n.º 7
0
class Controller(object):
    """Main class of Kytos.

    The main responsabilities of this class are:
        - start a thread with :class:`~.core.tcp_server.KytosServer`;
        - manage KytosNApps (install, load and unload);
        - keep the buffers (instance of :class:`~.core.buffers.KytosBuffers`);
        - manage which event should be sent to NApps methods;
        - manage the buffers handlers, considering one thread per handler.
    """

    # Created issue #568 for the disabled checks.
    # pylint: disable=too-many-instance-attributes,too-many-public-methods
    def __init__(self, options=None):
        """Init method of Controller class takes the parameters below.

        Args:
            options (:attr:`ParseArgs.args`): :attr:`options` attribute from an
                instance of :class:`~kytos.core.config.KytosConfig` class.
        """
        if options is None:
            options = KytosConfig().options['daemon']
        #: dict: keep the main threads of the controller (buffers and handler)
        self._threads = {}
        #: KytosBuffers: KytosBuffer object with Controller buffers
        self.buffers = KytosBuffers()
        #: dict: keep track of the socket connections labeled by ``(ip, port)``
        #:
        #: This dict stores all connections between the controller and the
        #: switches. The key for this dict is a tuple (ip, port). The content
        #: is another dict with the connection information.
        self.connections = {}
        #: dict: mapping of events and event listeners.
        #:
        #: The key of the dict is a KytosEvent (or a string that represent a
        #: regex to match agains KytosEvents) and the value is a list of
        #: methods that will receive the referenced event
        self.events_listeners = {
            'kytos/core.connection.new': [self.new_connection]
        }

        #: dict: Current loaded apps - 'napp_name': napp (instance)
        #:
        #: The key is the napp name (string), while the value is the napp
        #: instance itself.
        self.napps = {}
        #: Object generated by ParseArgs on config.py file
        self.options = options
        #: KytosServer: Instance of KytosServer that will be listening to TCP
        #: connections.
        self.server = None
        #: dict: Current existing switches.
        #:
        #: The key is the switch dpid, while the value is a Switch object.
        self.switches = {}  # dpid: Switch()

        #: datetime.datetime: Time when the controller finished starting.
        self.started_at = None

        #: logging.Logger: Logger instance used by Kytos.
        self.log = None

        #: API Server used to expose rest endpoints.
        self.api_server = APIServer(__name__, self.options.listen,
                                    self.options.api_port)

        self._register_endpoints()

        #: Observer that handle NApps when they are enabled or disabled.
        self.napp_dir_listener = NAppDirListener(self)

        #: Adding the napps 'enabled' directory into the PATH
        #: Now you can access the enabled napps with:
        #: from napps.<username>.<napp_name> import ?....
        sys.path.append(os.path.join(self.options.napps, os.pardir))

    def enable_logs(self):
        """Register kytos log and enable the logs."""
        LogManager.load_config_file(self.options.logging, self.options.debug)
        LogManager.enable_websocket(self.api_server.server)
        self.log = logging.getLogger(__name__)

    def start(self, restart=False):
        """Create pidfile and call start_controller method."""
        self.enable_logs()
        if not restart:
            self.create_pidfile()
        self.start_controller()

    def create_pidfile(self):
        """Create a pidfile."""
        pid = os.getpid()

        # Creates directory if it doesn't exist
        # System can erase /var/run's content
        pid_folder = Path(self.options.pidfile).parent
        self.log.info(pid_folder)

        # Pylint incorrectly infers Path objects
        # https://github.com/PyCQA/pylint/issues/224
        # pylint: disable=no-member
        if not pid_folder.exists():
            pid_folder.mkdir()
            pid_folder.chmod(0o1777)
        # pylint: enable=no-member

        # Make sure the file is deleted when controller stops
        atexit.register(Path(self.options.pidfile).unlink)

        # Checks if a pidfile exists. Creates a new file.
        try:
            pidfile = open(self.options.pidfile, mode='x')
        except OSError:
            # This happens if there is a pidfile already.
            # We shall check if the process that created the pidfile is still
            # running.
            try:
                existing_file = open(self.options.pidfile, mode='r')
                old_pid = int(existing_file.read())
                os.kill(old_pid, 0)
                # If kill() doesn't return an error, there's a process running
                # with the same PID. We assume it is Kytos and quit.
                # Otherwise, overwrite the file and proceed.
                error_msg = ("PID file {} exists. Delete it if Kytos is not "
                             "running. Aborting.")
                sys.exit(error_msg.format(self.options.pidfile))
            except OSError:
                try:
                    pidfile = open(self.options.pidfile, mode='w')
                except OSError as exception:
                    error_msg = "Failed to create pidfile {}: {}."
                    sys.exit(error_msg.format(self.options.pidfile, exception))

        # Identifies the process that created the pidfile.
        pidfile.write(str(pid))
        pidfile.close()

    def start_controller(self):
        """Start the controller.

        Starts a thread with the KytosServer (TCP Server).
        Starts a thread for each buffer handler.
        Load the installed apps.
        """
        self.log.info("Starting Kytos - Kytos Controller")
        self.server = KytosServer(
            (self.options.listen, int(self.options.port)), KytosRequestHandler,
            self, self.options.protocol_name)

        raw_event_handler = self.raw_event_handler
        msg_in_event_handler = self.msg_in_event_handler
        msg_out_event_handler = self.msg_out_event_handler
        app_event_handler = self.app_event_handler

        thrds = {
            'tcp_server':
            Thread(name='TCP server', target=self.server.serve_forever),
            'api_server':
            Thread(name='API server', target=self.api_server.run),
            'raw_event_handler':
            Thread(name='RawEvent Handler', target=raw_event_handler),
            'msg_in_event_handler':
            Thread(name='MsgInEvent Handler', target=msg_in_event_handler),
            'msg_out_event_handler':
            Thread(name='MsgOutEvent Handler', target=msg_out_event_handler),
            'app_event_handler':
            Thread(name='AppEvent Handler', target=app_event_handler)
        }

        self._threads = thrds
        # This is critical, if any of them started we should exit.
        for thread in self._threads.values():
            try:
                thread.start()
            except OSError as exception:
                error_msg = "Error starting thread {}: {}."
                sys.exit(error_msg.format(thread, exception))

        self.log.info("Loading Kytos NApps...")
        self.napp_dir_listener.start()
        self.load_napps()
        self.started_at = now()

    def _register_endpoints(self):
        """Register all rest endpoint served by kytos.

        -   Register APIServer endpoints
        -   Register WebUI endpoints
        -   Register ``/api/kytos/core/config`` endpoint
        """
        self.api_server.start_api()
        # Register controller endpoints as /api/kytos/core/...
        self.api_server.register_core_endpoint('config/',
                                               self.configuration_endpoint)

    def register_rest_endpoint(self, url, function, methods):
        """Deprecate in favor of @rest decorator."""
        self.api_server.register_rest_endpoint(url, function, methods)

    def configuration_endpoint(self):
        """Return the configuration options used by Kytos.

        Returns:
            string: Json with current configurations used by kytos.

        """
        return json.dumps(self.options.__dict__)

    def restart(self, graceful=True):
        """Restart Kytos SDN Controller.

        Args:
            graceful(bool): Represents the way that Kytos will restart.
        """
        if self.started_at is not None:
            self.stop(graceful)
            self.__init__(self.options)

        self.start(restart=True)

    def stop(self, graceful=True):
        """Shutdown all services used by kytos.

        This method should:
            - stop all Websockets
            - stop the API Server
            - stop the Controller
        """
        if self.started_at:
            self.stop_controller(graceful)

    def stop_controller(self, graceful=True):
        """Stop the controller.

        This method should:
            - announce on the network that the controller will shutdown;
            - stop receiving incoming packages;
            - call the 'shutdown' method of each KytosNApp that is running;
            - finish reading the events on all buffers;
            - stop each running handler;
            - stop all running threads;
            - stop the KytosServer;
        """
        self.log.info("Stopping Kytos")

        if not graceful:
            self.server.socket.close()

        self.server.shutdown()
        self.buffers.send_stop_signal()
        self.api_server.stop_api_server()
        self.napp_dir_listener.stop()

        for thread in self._threads.values():
            self.log.info("Stopping thread: %s", thread.name)
            thread.join()

        for thread in self._threads.values():
            while thread.is_alive():
                pass

        self.started_at = None
        self.unload_napps()
        self.buffers = KytosBuffers()
        self.server.server_close()

    def status(self):
        """Return status of Kytos Server.

        If the controller kytos is running this method will be returned
        "Running since 'Started_At'", otherwise "Stopped".

        Returns:
            string: String with kytos status.

        """
        if self.started_at:
            return "Running since %s" % self.started_at
        return "Stopped"

    def uptime(self):
        """Return the uptime of kytos server.

        This method should return:
            - 0 if Kytos Server is stopped.
            - (kytos.start_at - datetime.now) if Kytos Server is running.

        Returns:
           datetime.timedelta: The uptime interval.

        """
        return now() - self.started_at if self.started_at else 0

    def notify_listeners(self, event):
        """Send the event to the specified listeners.

        Loops over self.events_listeners matching (by regexp) the attribute
        name of the event with the keys of events_listeners. If a match occurs,
        then send the event to each registered listener.

        Args:
            event (~kytos.core.KytosEvent): An instance of a KytosEvent.
        """
        for event_regex, listeners in dict(self.events_listeners).items():
            # Do not match if the event has more characters
            # e.g. "shutdown" won't match "shutdown.kytos/of_core"
            if event_regex[-1] != '$' or event_regex[-2] == '\\':
                event_regex += '$'
            if re.match(event_regex, event.name):
                for listener in listeners:
                    listener(event)

    def raw_event_handler(self):
        """Handle raw events.

        This handler listen to the raw_buffer, get every event added to this
        buffer and sends it to the listeners listening to this event.

        It also verify if there is a switch instantiated on that connection_id
        `(ip, port)`. If a switch was found, then the `connection_id` attribute
        is set to `None` and the `dpid` is replaced with the switch dpid.
        """
        self.log.info("Raw Event Handler started")
        while True:
            event = self.buffers.raw.get()
            self.notify_listeners(event)
            self.log.debug("Raw Event handler called")

            if event.name == "kytos/core.shutdown":
                self.log.debug("RawEvent handler stopped")
                break

    def msg_in_event_handler(self):
        """Handle msg_in events.

        This handler listen to the msg_in_buffer, get every event added to this
        buffer and sends it to the listeners listening to this event.
        """
        self.log.info("Message In Event Handler started")
        while True:
            event = self.buffers.msg_in.get()
            self.notify_listeners(event)
            self.log.debug("MsgInEvent handler called")

            if event.name == "kytos/core.shutdown":
                self.log.debug("MsgInEvent handler stopped")
                break

    def msg_out_event_handler(self):
        """Handle msg_out events.

        This handler listen to the msg_out_buffer, get every event added to
        this buffer and sends it to the listeners listening to this event.
        """
        self.log.info("Message Out Event Handler started")
        while True:
            triggered_event = self.buffers.msg_out.get()

            if triggered_event.name == "kytos/core.shutdown":
                self.log.debug("MsgOutEvent handler stopped")
                break

            message = triggered_event.content['message']
            destination = triggered_event.destination
            if (destination
                    and not destination.state == ConnectionState.FINISHED):
                packet = message.pack()
                destination.send(packet)
                self.log.debug(
                    'Connection %s: OUT OFP, ' +
                    'version: %s, type: %s, xid: %s - %s', destination.id,
                    message.header.version, message.header.message_type,
                    message.header.xid, packet.hex())
                self.notify_listeners(triggered_event)
                self.log.debug("MsgOutEvent handler called")
            else:
                self.log.info("connection closed. Cannot send message")

    def app_event_handler(self):
        """Handle app events.

        This handler listen to the app_buffer, get every event added to this
        buffer and sends it to the listeners listening to this event.
        """
        self.log.info("App Event Handler started")
        while True:
            event = self.buffers.app.get()
            self.notify_listeners(event)
            self.log.debug("AppEvent handler called")

            if event.name == "kytos/core.shutdown":
                self.log.debug("AppEvent handler stopped")
                break

    def get_switch_by_dpid(self, dpid):
        """Return a specific switch by dpid.

        Args:
            dpid (|DPID|): dpid object used to identify a switch.

        Returns:
            :class:`~kytos.core.switch.Switch`: Switch with dpid specified.

        """
        return self.switches.get(dpid)

    def get_switch_or_create(self, dpid, connection):
        """Return switch or create it if necessary.

        Args:
            dpid (|DPID|): dpid object used to identify a switch.
            connection (:class:`~kytos.core.connection.Connection`):
                connection used by switch. If a switch has a connection that
                will be updated.

        Returns:
            :class:`~kytos.core.switch.Switch`: new or existent switch.

        """
        self.create_or_update_connection(connection)
        switch = self.get_switch_by_dpid(dpid)
        event = None

        if switch is None:
            switch = Switch(dpid=dpid)
            self.add_new_switch(switch)

            event = KytosEvent(name='kytos/core.switch.new',
                               content={'switch': switch})

        old_connection = switch.connection
        switch.update_connection(connection)

        if old_connection is not connection:
            self.remove_connection(old_connection)

        if event:
            self.buffers.app.put(event)

        return switch

    def create_or_update_connection(self, connection):
        """Update a connection.

        Args:
            connection (:class:`~kytos.core.connection.Connection`):
                Instance of connection that will be updated.
        """
        self.connections[connection.id] = connection

    def get_connection_by_id(self, conn_id):
        """Return a existent connection by id.

        Args:
            id (int): id from a connection.

        Returns:
            :class:`~kytos.core.connection.Connection`: Instance of connection
                or None Type.

        """
        return self.connections.get(conn_id)

    def remove_connection(self, connection):
        """Close a existent connection and remove it.

        Args:
            connection (:class:`~kytos.core.connection.Connection`):
                Instance of connection that will be removed.
        """
        if connection is None:
            return False

        try:
            connection.close()
            del self.connections[connection.id]
        except KeyError:
            return False

    def remove_switch(self, switch):
        """Remove a existent switch.

        Args:
            switch (:class:`~kytos.core.switch.Switch`):
                Instance of switch that will be removed.
        """
        try:
            del self.switches[switch.dpid]
        except KeyError:
            return False

    def new_connection(self, event):
        """Handle a kytos/core.connection.new event.

        This method will read new connection event and store the connection
        (socket) into the connections attribute on the controller.

        It also clear all references to the connection since it is a new
        connection on the same ip:port.

        Args:
            event (~kytos.core.KytosEvent):
                The received event (``kytos/core.connection.new``) with the
                needed infos.
        """
        self.log.info("Handling KytosEvent:kytos/core.connection.new ...")

        connection = event.source

        # Remove old connection (aka cleanup) if exists
        if self.get_connection_by_id(connection.id):
            self.remove_connection(connection.id)

        # Update connections with the new connection
        self.create_or_update_connection(connection)

    def add_new_switch(self, switch):
        """Add a new switch on the controller.

        Args:
            switch (Switch): A Switch object
        """
        self.switches[switch.dpid] = switch

    def load_napp(self, username, napp_name):
        """Load a single app.

        Load a single NAPP based on its name.

        Args:
            username (str): NApp username present in napp's path.
            napp_name (str): Name of the NApp to be loaded.

        Raises:
            FileNotFoundError: if napps' main.py is not found.

        """
        if (username, napp_name) in self.napps:
            message = 'NApp %s/%s was already loaded'
            self.log.warning(message, username, napp_name)
        else:
            mod_name = '.'.join(['napps', username, napp_name, 'main'])
            path = os.path.join(self.options.napps, username, napp_name,
                                'main.py')
            napp_spec = spec_from_file_location(mod_name, path)
            napp_module = module_from_spec(napp_spec)
            sys.modules[napp_spec.name] = napp_module
            napp_spec.loader.exec_module(napp_module)
            napp = napp_module.Main(controller=self)

            self.napps[(username, napp_name)] = napp

            # This start method is inherited from the Threading class.
            # It is not directly defined/declared on the KytosNApp class.
            napp.start()
            self.api_server.register_napp_endpoints(napp)

            # pylint: disable=protected-access
            for event, listeners in napp._listeners.items():
                self.events_listeners.setdefault(event, []).extend(listeners)
            # pylint: enable=protected-access

    def load_napps(self):
        """Load all NApps enabled on the NApps dir."""
        napps = NAppsManager(self)
        for napp in napps.list_enabled():
            try:
                self.log.info("Loading NApp %s", napp.id)
                self.load_napp(napp.username, napp.name)
            except FileNotFoundError as exception:
                self.log.error("Could not load NApp %s: %s", napp.id,
                               exception)

    def unload_napp(self, username, napp_name):
        """Unload a specific NApp.

        Args:
            username (str): NApp username.
            napp_name (str): Name of the NApp to be unloaded.
        """
        napp = self.napps.pop((username, napp_name), None)

        if napp is None:
            self.log.warning('NApp %s/%s was not loaded', username, napp_name)
        else:
            self.log.info("Shutting down NApp %s/%s...", username, napp_name)
            napp_id = NApp(username, napp_name).id
            event = KytosEvent(name='kytos/core.shutdown.' + napp_id)
            napp_shutdown_fn = self.events_listeners[event.name][0]
            # Call listener before removing it from events_listeners
            napp_shutdown_fn(event)

            # Remove rest endpoints from that napp
            self.api_server.remove_napp_endpoints(napp)

            # Removing listeners from that napp
            # pylint: disable=protected-access
            for event_type, napp_listeners in napp._listeners.items():
                event_listeners = self.events_listeners[event_type]
                for listener in napp_listeners:
                    event_listeners.remove(listener)
                if not event_listeners:
                    del self.events_listeners[event_type]
            # pylint: enable=protected-access

    def unload_napps(self):
        """Unload all loaded NApps that are not core NApps."""
        # list() is used here to avoid the error:
        # 'RuntimeError: dictionary changed size during iteration'
        # This is caused by looping over an dictionary while removing
        # items from it.
        for (username, napp_name) in list(self.napps.keys()):  # noqa
            self.unload_napp(username, napp_name)
Exemplo n.º 8
0
 def setUp(self):
     """Instantiate a APIServer."""
     self.api_server = APIServer('CustomName', False)
Exemplo n.º 9
0
class TestAPIServer(unittest.TestCase):
    """Test the class APIServer."""
    def setUp(self):
        """Instantiate a APIServer."""
        self.api_server = APIServer('CustomName', False)
        self.napps_manager = MagicMock()
        self.api_server.server = MagicMock()
        self.api_server.napps_manager = self.napps_manager
        self.api_server.napps_dir = 'napps_dir'
        self.api_server.flask_dir = 'flask_dir'

    def test_deprecation_warning(self):
        """Deprecated method should suggest @rest decorator."""
        with warnings.catch_warnings(record=True) as wrngs:
            warnings.simplefilter("always")  # trigger all warnings
            self.api_server.register_rest_endpoint('rule', lambda x: x,
                                                   ['POST'])
            self.assertEqual(1, len(wrngs))
            warning = wrngs[0]
            self.assertEqual(warning.category, DeprecationWarning)
            self.assertIn('@rest', str(warning.message))

    def test_run(self):
        """Test run method."""
        self.api_server.run()

        self.api_server.server.run.assert_called_with(self.api_server.app,
                                                      self.api_server.listen,
                                                      self.api_server.port)

    @patch('sys.exit')
    def test_run_error(self, mock_exit):
        """Test run method to error case."""
        self.api_server.server.run.side_effect = OSError
        self.api_server.run()

        mock_exit.assert_called()

    @patch('kytos.core.api_server.request')
    def test_shutdown_api(self, mock_request):
        """Test shutdown_api method."""
        mock_request.host = 'localhost:8181'

        self.api_server.shutdown_api()

        self.api_server.server.stop.assert_called()

    @patch('kytos.core.api_server.request')
    def test_shutdown_api__error(self, mock_request):
        """Test shutdown_api method to error case."""
        mock_request.host = 'any:port'

        self.api_server.shutdown_api()

        self.api_server.server.stop.assert_not_called()

    def test_status_api(self):
        """Test status_api method."""
        status = self.api_server.status_api()
        self.assertEqual(status, ('{"response": "running"}', 200))

    @patch('kytos.core.api_server.urlopen')
    def test_stop_api_server(self, mock_urlopen):
        """Test stop_api_server method."""
        self.api_server.stop_api_server()

        url = "%s/shutdown" % API_URI
        mock_urlopen.assert_called_with(url)

    @patch('kytos.core.api_server.send_file')
    @patch('os.path.exists', return_value=True)
    def test_static_web_ui__success(self, *args):
        """Test static_web_ui method to success case."""
        (_, mock_send_file) = args
        self.api_server.static_web_ui('kytos', 'napp', 'filename')

        mock_send_file.assert_called_with('napps_dir/kytos/napp/ui/filename')

    @patch('os.path.exists', return_value=False)
    def test_static_web_ui__error(self, _):
        """Test static_web_ui method to error case."""
        resp, code = self.api_server.static_web_ui('kytos', 'napp', 'filename')

        self.assertEqual(resp, '')
        self.assertEqual(code, 404)

    @patch('kytos.core.api_server.glob')
    def test_get_ui_components(self, mock_glob):
        """Test get_ui_components method."""
        with self.api_server.app.app_context():
            mock_glob.return_value = ['napps_dir/*/*/ui/*/*.kytos']
            response = self.api_server.get_ui_components('all')

            expected_json = [{'name': '*-*-*-*', 'url': 'ui/*/*/*/*.kytos'}]
            self.assertEqual(response.json, expected_json)
            self.assertEqual(response.status_code, 200)

    @patch('kytos.core.api_server.send_file')
    def test_web_ui(self, mock_send_file):
        """Test web_ui method."""
        self.api_server.web_ui()

        mock_send_file.assert_called_with('flask_dir/index.html')

    @patch('kytos.core.api_server.urlretrieve')
    @patch('kytos.core.api_server.urlopen')
    @patch('zipfile.ZipFile')
    @patch('os.path.exists')
    @patch('os.mkdir')
    @patch('shutil.move')
    def test_update_web_ui(self, *args):
        """Test update_web_ui method."""
        (_, _, mock_exists, mock_zipfile, mock_urlopen,
         mock_urlretrieve) = args
        zipfile = MagicMock()
        zipfile.testzip.return_value = None
        mock_zipfile.return_value = zipfile

        data = json.dumps({'tag_name': 1.0})
        url_response = MagicMock()
        url_response.readlines.return_value = [data]
        mock_urlopen.return_value = url_response

        mock_exists.side_effect = [False, True]

        response = self.api_server.update_web_ui()

        url = 'https://github.com/kytos/ui/releases/download/1.0/latest.zip'
        mock_urlretrieve.assert_called_with(url)
        self.assertEqual(response, 'updated the web ui')

    @patch('kytos.core.api_server.urlretrieve')
    @patch('kytos.core.api_server.urlopen')
    @patch('os.path.exists')
    def test_update_web_ui__http_error(self, *args):
        """Test update_web_ui method to http error case."""
        (mock_exists, mock_urlopen, mock_urlretrieve) = args

        data = json.dumps({'tag_name': 1.0})
        url_response = MagicMock()
        url_response.readlines.return_value = [data]
        mock_urlopen.return_value = url_response
        mock_urlretrieve.side_effect = HTTPError('url', 123, 'msg', 'hdrs',
                                                 MagicMock())

        mock_exists.return_value = False

        response = self.api_server.update_web_ui()

        expected_response = 'Uri not found https://github.com/kytos/ui/' + \
                            'releases/download/1.0/latest.zip.'
        self.assertEqual(response, expected_response)

    @patch('kytos.core.api_server.urlretrieve')
    @patch('kytos.core.api_server.urlopen')
    @patch('zipfile.ZipFile')
    @patch('os.path.exists')
    def test_update_web_ui__zip_error(self, *args):
        """Test update_web_ui method to error case in zip file."""
        (mock_exists, mock_zipfile, mock_urlopen, _) = args
        zipfile = MagicMock()
        zipfile.testzip.return_value = 'any'
        mock_zipfile.return_value = zipfile

        data = json.dumps({'tag_name': 1.0})
        url_response = MagicMock()
        url_response.readlines.return_value = [data]
        mock_urlopen.return_value = url_response

        mock_exists.return_value = False

        response = self.api_server.update_web_ui()

        expected_response = 'Zip file from https://github.com/kytos/ui/' + \
                            'releases/download/1.0/latest.zip is corrupted.'
        self.assertEqual(response, expected_response)

    def test_enable_napp__error_not_installed(self):
        """Test _enable_napp method error case when napp is not installed."""
        self.napps_manager.is_installed.return_value = False

        resp, code = self.api_server._enable_napp('kytos', 'napp')

        self.assertEqual(resp, '{"response": "not installed"}')
        self.assertEqual(code, 400)

    def test_enable_napp__error_not_enabling(self):
        """Test _enable_napp method error case when napp is not enabling."""
        self.napps_manager.is_installed.return_value = True
        self.napps_manager.is_enabled.side_effect = [False, False]

        resp, code = self.api_server._enable_napp('kytos', 'napp')

        self.assertEqual(resp, '{"response": "error"}')
        self.assertEqual(code, 500)

    def test_enable_napp__success(self):
        """Test _enable_napp method success case."""
        self.napps_manager.is_installed.return_value = True
        self.napps_manager.is_enabled.side_effect = [False, True]

        resp, code = self.api_server._enable_napp('kytos', 'napp')

        self.assertEqual(resp, '{"response": "enabled"}')
        self.assertEqual(code, 200)

    def test_disable_napp__error_not_installed(self):
        """Test _disable_napp method error case when napp is not installed."""
        self.napps_manager.is_installed.return_value = False

        resp, code = self.api_server._disable_napp('kytos', 'napp')

        self.assertEqual(resp, '{"response": "not installed"}')
        self.assertEqual(code, 400)

    def test_disable_napp__error_not_enabling(self):
        """Test _disable_napp method error case when napp is not enabling."""
        self.napps_manager.is_installed.return_value = True
        self.napps_manager.is_enabled.side_effect = [True, True]

        resp, code = self.api_server._disable_napp('kytos', 'napp')

        self.assertEqual(resp, '{"response": "error"}')
        self.assertEqual(code, 500)

    def test_disable_napp__success(self):
        """Test _disable_napp method success case."""
        self.napps_manager.is_installed.return_value = True
        self.napps_manager.is_enabled.side_effect = [True, False]

        resp, code = self.api_server._disable_napp('kytos', 'napp')

        self.assertEqual(resp, '{"response": "disabled"}')
        self.assertEqual(code, 200)

    def test_install_napp__error_not_installing(self):
        """Test _install_napp method error case when napp is not installing."""
        self.napps_manager.is_installed.return_value = False
        self.napps_manager.install.return_value = False

        resp, code = self.api_server._install_napp('kytos', 'napp')

        self.assertEqual(resp, '{"response": "error"}')
        self.assertEqual(code, 500)

    def test_install_napp__http_error(self):
        """Test _install_napp method to http error case."""
        self.napps_manager.is_installed.return_value = False
        self.napps_manager.install.side_effect = HTTPError(
            'url', 123, 'msg', 'hdrs', MagicMock())

        resp, code = self.api_server._install_napp('kytos', 'napp')

        self.assertEqual(resp, '{"response": "error"}')
        self.assertEqual(code, 123)

    def test_install_napp__success_is_installed(self):
        """Test _install_napp method success case when napp is installed."""
        self.napps_manager.is_installed.return_value = True

        resp, code = self.api_server._install_napp('kytos', 'napp')

        self.assertEqual(resp, '{"response": "installed"}')
        self.assertEqual(code, 200)

    def test_install_napp__success(self):
        """Test _install_napp method success case."""
        self.napps_manager.is_installed.return_value = False
        self.napps_manager.install.return_value = True

        resp, code = self.api_server._install_napp('kytos', 'napp')

        self.assertEqual(resp, '{"response": "installed"}')
        self.assertEqual(code, 200)

    def test_uninstall_napp__error_not_uninstalling(self):
        """Test _uninstall_napp method error case when napp is not
           uninstalling.
        """
        self.napps_manager.is_installed.return_value = True
        self.napps_manager.uninstall.return_value = False

        resp, code = self.api_server._uninstall_napp('kytos', 'napp')

        self.assertEqual(resp, '{"response": "error"}')
        self.assertEqual(code, 500)

    def test_uninstall_napp__success_not_installed(self):
        """Test _uninstall_napp method success case when napp is not
           installed.
        """
        self.napps_manager.is_installed.return_value = False

        resp, code = self.api_server._uninstall_napp('kytos', 'napp')

        self.assertEqual(resp, '{"response": "uninstalled"}')
        self.assertEqual(code, 200)

    def test_uninstall_napp__success(self):
        """Test _uninstall_napp method success case."""
        self.napps_manager.is_installed.return_value = True
        self.napps_manager.uninstall.return_value = True

        resp, code = self.api_server._uninstall_napp('kytos', 'napp')

        self.assertEqual(resp, '{"response": "uninstalled"}')
        self.assertEqual(code, 200)

    def test_list_enabled_napps(self):
        """Test _list_enabled_napps method."""
        napp = MagicMock()
        napp.username = '******'
        napp.name = 'name'
        self.napps_manager.get_enabled_napps.return_value = [napp]

        enabled_napps, code = self.api_server._list_enabled_napps()

        self.assertEqual(enabled_napps, '{"napps": [["kytos", "name"]]}')
        self.assertEqual(code, 200)

    def test_list_installed_napps(self):
        """Test _list_installed_napps method."""
        napp = MagicMock()
        napp.username = '******'
        napp.name = 'name'
        self.napps_manager.get_installed_napps.return_value = [napp]

        enabled_napps, code = self.api_server._list_installed_napps()

        self.assertEqual(enabled_napps, '{"napps": [["kytos", "name"]]}')
        self.assertEqual(code, 200)

    def test_get_napp_metadata__not_installed(self):
        """Test _get_napp_metadata method to error case when napp is not
           installed."""
        self.napps_manager.is_installed.return_value = False
        resp, code = self.api_server._get_napp_metadata(
            'kytos', 'napp', 'version')

        self.assertEqual(resp, 'NApp is not installed.')
        self.assertEqual(code, 400)

    def test_get_napp_metadata__invalid_key(self):
        """Test _get_napp_metadata method to error case when key is invalid."""
        self.napps_manager.is_installed.return_value = True
        resp, code = self.api_server._get_napp_metadata('kytos', 'napp', 'any')

        self.assertEqual(resp, 'Invalid key.')
        self.assertEqual(code, 400)

    def test_get_napp_metadata(self):
        """Test _get_napp_metadata method."""
        data = '{"username": "******", \
                 "name": "napp", \
                 "version": "1.0"}'

        self.napps_manager.is_installed.return_value = True
        self.napps_manager.get_napp_metadata.return_value = data
        resp, code = self.api_server._get_napp_metadata(
            'kytos', 'napp', 'version')

        expected_metadata = json.dumps({'version': data})
        self.assertEqual(resp, expected_metadata)
        self.assertEqual(code, 200)

    @staticmethod
    def __custom_endpoint():
        """Custom method used by APIServer."""
        return "Custom Endpoint"
Exemplo n.º 10
0
 def _add_function_paths(self, decorators_str):
     for rule, parsed_methods in self._parse_decorators(decorators_str):
         absolute_rule = APIServer.get_absolute_rule(rule, self._napp)
         path_url = self._rule2path(absolute_rule)
         path_methods = self._paths.setdefault(path_url, {})
         self._add_methods(parsed_methods, path_methods)
Exemplo n.º 11
0
    def __init__(self, options=None, loop=None):
        """Init method of Controller class takes the parameters below.

        Args:
            options (:attr:`ParseArgs.args`): :attr:`options` attribute from an
                instance of :class:`~kytos.core.config.KytosConfig` class.
        """
        if options is None:
            options = KytosConfig().options['daemon']

        self._loop = loop or asyncio.get_event_loop()
        self._pool = ThreadPoolExecutor(max_workers=1)

        #: dict: keep the main threads of the controller (buffers and handler)
        self._threads = {}
        #: KytosBuffers: KytosBuffer object with Controller buffers
        self.buffers = KytosBuffers(loop=self._loop)
        #: dict: keep track of the socket connections labeled by ``(ip, port)``
        #:
        #: This dict stores all connections between the controller and the
        #: switches. The key for this dict is a tuple (ip, port). The content
        #: is another dict with the connection information.
        self.connections = {}
        #: dict: mapping of events and event listeners.
        #:
        #: The key of the dict is a KytosEvent (or a string that represent a
        #: regex to match agains KytosEvents) and the value is a list of
        #: methods that will receive the referenced event
        self.events_listeners = {'kytos/core.connection.new':
                                 [self.new_connection]}

        #: dict: Current loaded apps - ``'napp_name'``: ``napp`` (instance)
        #:
        #: The key is the napp name (string), while the value is the napp
        #: instance itself.
        self.napps = {}
        #: Object generated by ParseArgs on config.py file
        self.options = options
        #: KytosServer: Instance of KytosServer that will be listening to TCP
        #: connections.
        self.server = None
        #: dict: Current existing switches.
        #:
        #: The key is the switch dpid, while the value is a Switch object.
        self.switches = {}  # dpid: Switch()

        #: datetime.datetime: Time when the controller finished starting.
        self.started_at = None

        #: logging.Logger: Logger instance used by Kytos.
        self.log = None

        #: API Server used to expose rest endpoints.
        self.api_server = APIServer(__name__, self.options.listen,
                                    self.options.api_port,
                                    napps_dir=self.options.napps)

        self._register_endpoints()

        #: Observer that handle NApps when they are enabled or disabled.
        self.napp_dir_listener = NAppDirListener(self)

        self.napps_manager = NAppsManager(self)

        #: Adding the napps 'enabled' directory into the PATH
        #: Now you can access the enabled napps with:
        #: from napps.<username>.<napp_name> import ?....
        sys.path.append(os.path.join(self.options.napps, os.pardir))
Exemplo n.º 12
0
class Controller:
    """Main class of Kytos.

    The main responsibilities of this class are:
        - start a thread with :class:`~.core.tcp_server.KytosServer`;
        - manage KytosNApps (install, load and unload);
        - keep the buffers (instance of :class:`~.core.buffers.KytosBuffers`);
        - manage which event should be sent to NApps methods;
        - manage the buffers handlers, considering one thread per handler.
    """

    # Created issue #568 for the disabled checks.
    # pylint: disable=too-many-instance-attributes,too-many-public-methods
    def __init__(self, options=None, loop=None):
        """Init method of Controller class takes the parameters below.

        Args:
            options (:attr:`ParseArgs.args`): :attr:`options` attribute from an
                instance of :class:`~kytos.core.config.KytosConfig` class.
        """
        if options is None:
            options = KytosConfig().options['daemon']

        self._loop = loop or asyncio.get_event_loop()
        self._pool = ThreadPoolExecutor(max_workers=1)

        #: dict: keep the main threads of the controller (buffers and handler)
        self._threads = {}
        #: KytosBuffers: KytosBuffer object with Controller buffers
        self.buffers = KytosBuffers(loop=self._loop)
        #: dict: keep track of the socket connections labeled by ``(ip, port)``
        #:
        #: This dict stores all connections between the controller and the
        #: switches. The key for this dict is a tuple (ip, port). The content
        #: is another dict with the connection information.
        self.connections = {}
        #: dict: mapping of events and event listeners.
        #:
        #: The key of the dict is a KytosEvent (or a string that represent a
        #: regex to match agains KytosEvents) and the value is a list of
        #: methods that will receive the referenced event
        self.events_listeners = {'kytos/core.connection.new':
                                 [self.new_connection]}

        #: dict: Current loaded apps - ``'napp_name'``: ``napp`` (instance)
        #:
        #: The key is the napp name (string), while the value is the napp
        #: instance itself.
        self.napps = {}
        #: Object generated by ParseArgs on config.py file
        self.options = options
        #: KytosServer: Instance of KytosServer that will be listening to TCP
        #: connections.
        self.server = None
        #: dict: Current existing switches.
        #:
        #: The key is the switch dpid, while the value is a Switch object.
        self.switches = {}  # dpid: Switch()

        #: datetime.datetime: Time when the controller finished starting.
        self.started_at = None

        #: logging.Logger: Logger instance used by Kytos.
        self.log = None

        #: API Server used to expose rest endpoints.
        self.api_server = APIServer(__name__, self.options.listen,
                                    self.options.api_port,
                                    napps_dir=self.options.napps)

        self._register_endpoints()

        #: Observer that handle NApps when they are enabled or disabled.
        self.napp_dir_listener = NAppDirListener(self)

        self.napps_manager = NAppsManager(self)

        #: Adding the napps 'enabled' directory into the PATH
        #: Now you can access the enabled napps with:
        #: from napps.<username>.<napp_name> import ?....
        sys.path.append(os.path.join(self.options.napps, os.pardir))

    def enable_logs(self):
        """Register kytos log and enable the logs."""
        LogManager.load_config_file(self.options.logging, self.options.debug)
        LogManager.enable_websocket(self.api_server.server)
        self.log = logging.getLogger("controller")

    def start(self, restart=False):
        """Create pidfile and call start_controller method."""
        self.enable_logs()
        if not restart:
            self.create_pidfile()
        self.start_controller()

    def create_pidfile(self):
        """Create a pidfile."""
        pid = os.getpid()

        # Creates directory if it doesn't exist
        # System can erase /var/run's content
        pid_folder = Path(self.options.pidfile).parent
        self.log.info(pid_folder)

        # Pylint incorrectly infers Path objects
        # https://github.com/PyCQA/pylint/issues/224
        # pylint: disable=no-member
        if not pid_folder.exists():
            pid_folder.mkdir()
            pid_folder.chmod(0o1777)
        # pylint: enable=no-member

        # Make sure the file is deleted when controller stops
        atexit.register(Path(self.options.pidfile).unlink)

        # Checks if a pidfile exists. Creates a new file.
        try:
            pidfile = open(self.options.pidfile, mode='x')
        except OSError:
            # This happens if there is a pidfile already.
            # We shall check if the process that created the pidfile is still
            # running.
            try:
                existing_file = open(self.options.pidfile, mode='r')
                old_pid = int(existing_file.read())
                os.kill(old_pid, 0)
                # If kill() doesn't return an error, there's a process running
                # with the same PID. We assume it is Kytos and quit.
                # Otherwise, overwrite the file and proceed.
                error_msg = ("PID file {} exists. Delete it if Kytos is not "
                             "running. Aborting.")
                sys.exit(error_msg.format(self.options.pidfile))
            except OSError:
                try:
                    pidfile = open(self.options.pidfile, mode='w')
                except OSError as exception:
                    error_msg = "Failed to create pidfile {}: {}."
                    sys.exit(error_msg.format(self.options.pidfile, exception))

        # Identifies the process that created the pidfile.
        pidfile.write(str(pid))
        pidfile.close()

    def start_controller(self):
        """Start the controller.

        Starts the KytosServer (TCP Server) coroutine.
        Starts a thread for each buffer handler.
        Load the installed apps.
        """
        self.log.info("Starting Kytos - Kytos Controller")
        self.server = KytosServer((self.options.listen,
                                   int(self.options.port)),
                                  KytosServerProtocol,
                                  self,
                                  self.options.protocol_name)

        self.log.info("Starting TCP server: %s", self.server)
        self.server.serve_forever()

        def _stop_loop(_):
            loop = asyncio.get_event_loop()
            # print(_.result())
            threads = threading.enumerate()
            self.log.debug("%s threads before loop.stop: %s",
                           len(threads), threads)
            loop.stop()

        async def _run_api_server_thread(executor):
            log = logging.getLogger('controller.api_server_thread')
            log.debug('starting')
            # log.debug('creating tasks')
            loop = asyncio.get_event_loop()
            blocking_tasks = [
                loop.run_in_executor(executor, self.api_server.run)
            ]
            # log.debug('waiting for tasks')
            completed, pending = await asyncio.wait(blocking_tasks)
            # results = [t.result() for t in completed]
            # log.debug('results: {!r}'.format(results))
            log.debug('completed: %d, pending: %d',
                      len(completed), len(pending))

        task = self._loop.create_task(self.raw_event_handler())
        task = self._loop.create_task(self.msg_in_event_handler())
        task = self._loop.create_task(self.msg_out_event_handler())
        task = self._loop.create_task(self.app_event_handler())
        task = self._loop.create_task(_run_api_server_thread(self._pool))
        task.add_done_callback(_stop_loop)

        self.log.info("ThreadPool started: %s", self._pool)

        # ASYNC TODO: ensure all threads started correctly
        # This is critical, if any of them failed starting we should exit.
        # sys.exit(error_msg.format(thread, exception))

        self.log.info("Loading Kytos NApps...")
        self.napp_dir_listener.start()
        self.pre_install_napps(self.options.napps_pre_installed)
        self.load_napps()

        self.started_at = now()

    def _register_endpoints(self):
        """Register all rest endpoint served by kytos.

        -   Register APIServer endpoints
        -   Register WebUI endpoints
        -   Register ``/api/kytos/core/config`` endpoint
        """
        self.api_server.start_api()
        # Register controller endpoints as /api/kytos/core/...
        self.api_server.register_core_endpoint('config/',
                                               self.configuration_endpoint)

        self.api_server.register_core_endpoint(
            'reload/<username>/<napp_name>/',
            self.rest_reload_napp)
        self.api_server.register_core_endpoint('reload/all',
                                               self.rest_reload_all_napps)

    def register_rest_endpoint(self, url, function, methods):
        """Deprecate in favor of @rest decorator."""
        self.api_server.register_rest_endpoint(url, function, methods)

    def configuration_endpoint(self):
        """Return the configuration options used by Kytos.

        Returns:
            string: Json with current configurations used by kytos.

        """
        return json.dumps(self.options.__dict__)

    def restart(self, graceful=True):
        """Restart Kytos SDN Controller.

        Args:
            graceful(bool): Represents the way that Kytos will restart.
        """
        if self.started_at is not None:
            self.stop(graceful)
            self.__init__(self.options)

        self.start(restart=True)

    def stop(self, graceful=True):
        """Shutdown all services used by kytos.

        This method should:
            - stop all Websockets
            - stop the API Server
            - stop the Controller
        """
        if self.started_at:
            self.stop_controller(graceful)

    def stop_controller(self, graceful=True):
        """Stop the controller.

        This method should:
            - announce on the network that the controller will shutdown;
            - stop receiving incoming packages;
            - call the 'shutdown' method of each KytosNApp that is running;
            - finish reading the events on all buffers;
            - stop each running handler;
            - stop all running threads;
            - stop the KytosServer;
        """
        self.log.info("Stopping Kytos")

        self.buffers.send_stop_signal()
        self.api_server.stop_api_server()
        self.napp_dir_listener.stop()

        self.log.info("Stopping threadpool: %s", self._pool)

        threads = threading.enumerate()
        self.log.debug("%s threads before threadpool shutdown: %s",
                       len(threads), threads)

        self._pool.shutdown(wait=graceful)

        # self.server.socket.shutdown()
        # self.server.socket.close()

        # for thread in self._threads.values():
        #     self.log.info("Stopping thread: %s", thread.name)
        #     thread.join()

        # for thread in self._threads.values():
        #     while thread.is_alive():
        #         self.log.info("Thread is alive: %s", thread.name)
        #         pass

        self.started_at = None
        self.unload_napps()
        self.buffers = KytosBuffers()

        # ASYNC TODO: close connections
        # self.server.server_close()

        # Shutdown the TCP server and the main asyncio loop
        self.server.shutdown()

    def status(self):
        """Return status of Kytos Server.

        If the controller kytos is running this method will be returned
        "Running since 'Started_At'", otherwise "Stopped".

        Returns:
            string: String with kytos status.

        """
        if self.started_at:
            return "Running since %s" % self.started_at
        return "Stopped"

    def uptime(self):
        """Return the uptime of kytos server.

        This method should return:
            - 0 if Kytos Server is stopped.
            - (kytos.start_at - datetime.now) if Kytos Server is running.

        Returns:
           datetime.timedelta: The uptime interval.

        """
        return now() - self.started_at if self.started_at else 0

    def notify_listeners(self, event):
        """Send the event to the specified listeners.

        Loops over self.events_listeners matching (by regexp) the attribute
        name of the event with the keys of events_listeners. If a match occurs,
        then send the event to each registered listener.

        Args:
            event (~kytos.core.KytosEvent): An instance of a KytosEvent.
        """
        self.log.debug("looking for listeners for %s", event)
        for event_regex, listeners in dict(self.events_listeners).items():
            # self.log.debug("listeners found for %s: %r => %s", event,
            #                event_regex, [l.__qualname__ for l in listeners])
            # Do not match if the event has more characters
            # e.g. "shutdown" won't match "shutdown.kytos/of_core"
            if event_regex[-1] != '$' or event_regex[-2] == '\\':
                event_regex += '$'
            if re.match(event_regex, event.name):
                # self.log.debug('Calling listeners for %s', event)
                for listener in listeners:
                    listener(event)

    async def raw_event_handler(self):
        """Handle raw events.

        Listen to the raw_buffer and send all its events to the
        corresponding listeners.
        """
        self.log.info("Raw Event Handler started")
        while True:
            event = await self.buffers.raw.aget()
            self.notify_listeners(event)
            self.log.debug("Raw Event handler called")

            if event.name == "kytos/core.shutdown":
                self.log.debug("Raw Event handler stopped")
                break

    async def msg_in_event_handler(self):
        """Handle msg_in events.

        Listen to the msg_in buffer and send all its events to the
        corresponding listeners.
        """
        self.log.info("Message In Event Handler started")
        while True:
            event = await self.buffers.msg_in.aget()
            self.notify_listeners(event)
            self.log.debug("Message In Event handler called")

            if event.name == "kytos/core.shutdown":
                self.log.debug("Message In Event handler stopped")
                break

    async def msg_out_event_handler(self):
        """Handle msg_out events.

        Listen to the msg_out buffer and send all its events to the
        corresponding listeners.
        """
        self.log.info("Message Out Event Handler started")
        while True:
            triggered_event = await self.buffers.msg_out.aget()

            if triggered_event.name == "kytos/core.shutdown":
                self.log.debug("Message Out Event handler stopped")
                break

            message = triggered_event.content['message']
            destination = triggered_event.destination
            if (destination and
                    not destination.state == ConnectionState.FINISHED):
                packet = message.pack()
                destination.send(packet)
                self.log.debug('Connection %s: OUT OFP, '
                               'version: %s, type: %s, xid: %s - %s',
                               destination.id,
                               message.header.version,
                               message.header.message_type,
                               message.header.xid,
                               packet.hex())
                self.notify_listeners(triggered_event)
                self.log.debug("Message Out Event handler called")
            else:
                self.log.info("connection closed. Cannot send message")

    async def app_event_handler(self):
        """Handle app events.

        Listen to the app buffer and send all its events to the
        corresponding listeners.
        """
        self.log.info("App Event Handler started")
        while True:
            event = await self.buffers.app.aget()
            self.notify_listeners(event)
            self.log.debug("App Event handler called")

            if event.name == "kytos/core.shutdown":
                self.log.debug("App Event handler stopped")
                break

    def get_interface_by_id(self, interface_id):
        """Find a Interface  with interface_id.

        Args:
            interface_id(str): Interface Identifier.

        Returns:
            Interface: Instance of Interface with the id given.

        """
        if interface_id is None:
            return None

        switch_id = ":".join(interface_id.split(":")[:-1])
        interface_number = int(interface_id.split(":")[-1])

        switch = self.switches.get(switch_id)

        if not switch:
            return None

        return switch.interfaces.get(interface_number, None)

    def get_switch_by_dpid(self, dpid):
        """Return a specific switch by dpid.

        Args:
            dpid (|DPID|): dpid object used to identify a switch.

        Returns:
            :class:`~kytos.core.switch.Switch`: Switch with dpid specified.

        """
        return self.switches.get(dpid)

    def get_switch_or_create(self, dpid, connection):
        """Return switch or create it if necessary.

        Args:
            dpid (|DPID|): dpid object used to identify a switch.
            connection (:class:`~kytos.core.connection.Connection`):
                connection used by switch. If a switch has a connection that
                will be updated.

        Returns:
            :class:`~kytos.core.switch.Switch`: new or existent switch.

        """
        self.create_or_update_connection(connection)
        switch = self.get_switch_by_dpid(dpid)
        event_name = 'kytos/core.switch.'

        if switch is None:
            switch = Switch(dpid=dpid)
            self.add_new_switch(switch)
            event_name += 'new'
        else:
            event_name += 'reconnected'

        self.set_switch_options(dpid=dpid)
        event = KytosEvent(name=event_name, content={'switch': switch})

        old_connection = switch.connection
        switch.update_connection(connection)

        if old_connection is not connection:
            self.remove_connection(old_connection)

        self.buffers.app.put(event)

        return switch

    def set_switch_options(self, dpid):
        """Update the switch settings based on kytos.conf options.

        Args:
            dpid (str): dpid used to identify a switch.

        """
        switch = self.switches.get(dpid)
        if not switch:
            return

        vlan_pool = {}
        try:
            vlan_pool = json.loads(self.options.vlan_pool)
            if not vlan_pool:
                return
        except (TypeError, json.JSONDecodeError) as err:
            self.log.error("Invalid vlan_pool settings: %s", err)

        if vlan_pool.get(dpid):
            self.log.info(f"Loading vlan_pool configuration for dpid {dpid}")
            for intf_num, port_list in vlan_pool[dpid].items():
                if not switch.interfaces.get((intf_num)):
                    vlan_ids = set()
                    for vlan_range in port_list:
                        (vlan_begin, vlan_end) = (vlan_range[0:2])
                        for vlan_id in range(vlan_begin, vlan_end):
                            vlan_ids.add(vlan_id)
                    intf_num = int(intf_num)
                    intf = Interface(name=intf_num, port_number=intf_num,
                                     switch=switch)
                    intf.set_available_tags(vlan_ids)
                    switch.update_interface(intf)

    def create_or_update_connection(self, connection):
        """Update a connection.

        Args:
            connection (:class:`~kytos.core.connection.Connection`):
                Instance of connection that will be updated.
        """
        self.connections[connection.id] = connection

    def get_connection_by_id(self, conn_id):
        """Return a existent connection by id.

        Args:
            id (int): id from a connection.

        Returns:
            :class:`~kytos.core.connection.Connection`: Instance of connection
                or None Type.

        """
        return self.connections.get(conn_id)

    def remove_connection(self, connection):
        """Close a existent connection and remove it.

        Args:
            connection (:class:`~kytos.core.connection.Connection`):
                Instance of connection that will be removed.
        """
        if connection is None:
            return False

        try:
            connection.close()
            del self.connections[connection.id]
        except KeyError:
            return False
        return True

    def remove_switch(self, switch):
        """Remove an existent switch.

        Args:
            switch (:class:`~kytos.core.switch.Switch`):
                Instance of switch that will be removed.
        """
        try:
            del self.switches[switch.dpid]
        except KeyError:
            return False
        return True

    def new_connection(self, event):
        """Handle a kytos/core.connection.new event.

        This method will read new connection event and store the connection
        (socket) into the connections attribute on the controller.

        It also clear all references to the connection since it is a new
        connection on the same ip:port.

        Args:
            event (~kytos.core.KytosEvent):
                The received event (``kytos/core.connection.new``) with the
                needed info.
        """
        self.log.info("Handling %s...", event)

        connection = event.source
        self.log.debug("Event source: %s", event.source)

        # Remove old connection (aka cleanup) if it exists
        if self.get_connection_by_id(connection.id):
            self.remove_connection(connection.id)

        # Update connections with the new connection
        self.create_or_update_connection(connection)

    def add_new_switch(self, switch):
        """Add a new switch on the controller.

        Args:
            switch (Switch): A Switch object
        """
        self.switches[switch.dpid] = switch

    def _import_napp(self, username, napp_name):
        """Import a NApp module.

        Raises:
            FileNotFoundError: if NApp's main.py is not found.
            ModuleNotFoundError: if any NApp requirement is not installed.

        """
        mod_name = '.'.join(['napps', username, napp_name, 'main'])
        path = os.path.join(self.options.napps, username, napp_name,
                            'main.py')
        napp_spec = spec_from_file_location(mod_name, path)
        napp_module = module_from_spec(napp_spec)
        sys.modules[napp_spec.name] = napp_module
        napp_spec.loader.exec_module(napp_module)
        return napp_module

    def load_napp(self, username, napp_name):
        """Load a single NApp.

        Args:
            username (str): NApp username (makes up NApp's path).
            napp_name (str): Name of the NApp to be loaded.
        """
        if (username, napp_name) in self.napps:
            message = 'NApp %s/%s was already loaded'
            self.log.warning(message, username, napp_name)
            return

        try:
            napp_module = self._import_napp(username, napp_name)
        except ModuleNotFoundError as err:
            self.log.error("Error loading NApp '%s/%s': %s",
                           username, napp_name, err)
            return
        except FileNotFoundError as err:
            msg = "NApp module not found, assuming it's a meta napp: %s"
            self.log.warning(msg, err.filename)
            return

        napp = napp_module.Main(controller=self)

        self.napps[(username, napp_name)] = napp

        napp.start()
        self.api_server.register_napp_endpoints(napp)

        # pylint: disable=protected-access
        for event, listeners in napp._listeners.items():
            self.events_listeners.setdefault(event, []).extend(listeners)
        # pylint: enable=protected-access

    def pre_install_napps(self, napps, enable=True):
        """Pre install and enable NApps.

        Before installing, it'll check if it's installed yet.

        Args:
            napps ([str]): List of NApps to be pre-installed and enabled.
        """
        all_napps = self.napps_manager.get_installed_napps()
        installed = [str(napp) for napp in all_napps]
        napps_diff = [napp for napp in napps if napp not in installed]
        for napp in napps_diff:
            self.napps_manager.install(napp, enable=enable)

    def load_napps(self):
        """Load all NApps enabled on the NApps dir."""
        for napp in self.napps_manager.get_enabled_napps():
            try:
                self.log.info("Loading NApp %s", napp.id)
                self.load_napp(napp.username, napp.name)
            except FileNotFoundError as exception:
                self.log.error("Could not load NApp %s: %s",
                               napp.id, exception)

    def unload_napp(self, username, napp_name):
        """Unload a specific NApp.

        Args:
            username (str): NApp username.
            napp_name (str): Name of the NApp to be unloaded.
        """
        napp = self.napps.pop((username, napp_name), None)

        if napp is None:
            self.log.warning('NApp %s/%s was not loaded', username, napp_name)
        else:
            self.log.info("Shutting down NApp %s/%s...", username, napp_name)
            napp_id = NApp(username, napp_name).id
            event = KytosEvent(name='kytos/core.shutdown.' + napp_id)
            napp_shutdown_fn = self.events_listeners[event.name][0]
            # Call listener before removing it from events_listeners
            napp_shutdown_fn(event)

            # Remove rest endpoints from that napp
            self.api_server.remove_napp_endpoints(napp)

            # Removing listeners from that napp
            # pylint: disable=protected-access
            for event_type, napp_listeners in napp._listeners.items():
                event_listeners = self.events_listeners[event_type]
                for listener in napp_listeners:
                    event_listeners.remove(listener)
                if not event_listeners:
                    del self.events_listeners[event_type]
            # pylint: enable=protected-access

    def unload_napps(self):
        """Unload all loaded NApps that are not core NApps."""
        # list() is used here to avoid the error:
        # 'RuntimeError: dictionary changed size during iteration'
        # This is caused by looping over an dictionary while removing
        # items from it.
        for (username, napp_name) in list(self.napps.keys()):  # noqa
            self.unload_napp(username, napp_name)

    def reload_napp_module(self, username, napp_name, napp_file):
        """Reload a NApp Module."""
        mod_name = '.'.join(['napps', username, napp_name, napp_file])
        try:
            napp_module = import_module(mod_name)
        except ModuleNotFoundError as err:
            self.log.error("Module '%s' not found", mod_name)
            raise
        try:
            napp_module = reload_module(napp_module)
        except ImportError as err:
            self.log.error("Error reloading NApp '%s/%s': %s",
                           username, napp_name, err)
            raise

    def reload_napp(self, username, napp_name):
        """Reload a NApp."""
        self.unload_napp(username, napp_name)
        try:
            self.reload_napp_module(username, napp_name, 'settings')
            self.reload_napp_module(username, napp_name, 'main')
        except (ModuleNotFoundError, ImportError):
            return 400
        self.log.info("NApp '%s/%s' successfully reloaded",
                      username, napp_name)
        self.load_napp(username, napp_name)
        return 200

    def rest_reload_napp(self, username, napp_name):
        """Request reload a NApp."""
        res = self.reload_napp(username, napp_name)
        return 'reloaded', res

    def rest_reload_all_napps(self):
        """Request reload all NApps."""
        for napp in self.napps:
            self.reload_napp(*napp)
        return 'reloaded', 200