exabgp.reactor.loop.Reactor.neighbor_cli_data() - Code Metrics - Inspection of "move configuration testing in its own section" - Exa-Networks/exabgp - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Push — master ( ea37f3...9aacac )

by Thomas

created 2020-05-17 00:13 UTC

exabgp.reactor.loop.Reactor.neighbor_cli_data() A

↳ Parent: exabgp.reactor.loop

Complexity

Conditions

Size

Total Lines	6
Code Lines	6

Duplication

Lines	0
Ratio	0 %

Importance

Changes

Metric	Value
cc	2
eloc	6
nop	2
dl	0
loc	6
rs	10
c	0
b	0
f	0

# encoding: utf-8
"""
reactor/loop.py

Created by Thomas Mangin on 2012-06-10.
Copyright (c) 2009-2017 Exa Networks. All rights reserved.
License: 3-clause BSD. (See the COPYRIGHT file)
"""

import time
import uuid
import select
import socket

from exabgp.reactor.daemon import Daemon
from exabgp.reactor.listener import Listener
from exabgp.reactor.api.processes import Processes
from exabgp.reactor.api.processes import ProcessError
from exabgp.reactor.peer import Peer
from exabgp.reactor.peer import ACTION
from exabgp.reactor.asynchronous import ASYNC
from exabgp.reactor.interrupt import Signal

from exabgp.reactor.api import API
from exabgp.configuration.configuration import Configuration
from exabgp.environment import getenv

from exabgp.bgp.fsm import FSM

from exabgp.version import version
from exabgp.logger import log


class Reactor(object):
    class Exit(object):
        normal = 0
        validate = 0
        listening = 1
        configuration = 1
        privileges = 1
        log = 1
        pid = 1
        socket = 1
        io_error = 1
        process = 1
        select = 1
        unknown = 1

    # [hex(ord(c)) for c in os.popen('clear').read()]
    clear = b''.join(bytes([int(c, 16)]) for c in ['0x1b', '0x5b', '0x48', '0x1b', '0x5b', '0x32', '0x4a'])

    def __init__(self, configurations):
        self._ips = getenv().tcp.bind
        self._port = getenv().tcp.port
        self._stopping = getenv().tcp.once
        self.exit_code = self.Exit.unknown

        self.max_loop_time = getenv().reactor.speed
        self._sleep_time = self.max_loop_time / 100
        self._busyspin = {}
        self._ratelimit = {}
        self.early_drop = getenv().daemon.drop

        self.processes = None

        self.configuration = Configuration(configurations)
        self.asynchronous = ASYNC()
        self.signal = Signal()
        self.daemon = Daemon(self)
        self.listener = Listener(self)
        self.api = API(self)

        self._peers = {}

        self._saved_pid = False
        self._poller = select.poll()

    def _termination(self, reason, exit_code):
        self.exit_code = exit_code
        self.signal.received = Signal.SHUTDOWN
        log.critical(reason, 'reactor')

    def _prevent_spin(self):
        second = int(time.time())
        if not second in self._busyspin:
            self._busyspin = {second: 0}
        self._busyspin[second] += 1
        if self._busyspin[second] > self.max_loop_time:
            time.sleep(self._sleep_time)
            return True
        return False

    def _rate_limited(self, peer, rate):
        if rate <= 0:
            return False
        second = int(time.time())
        ratelimit = self._ratelimit.get(peer, {})
        if not second in ratelimit:
            self._ratelimit[peer] = {second: rate - 1}
            return False
        if self._ratelimit[peer][second] > 0:
            self._ratelimit[peer][second] -= 1
            return False
        return True

    def _wait_for_io(self, sleeptime):
        spin_prevention = False
        try:
            for fd, event in self._poller.poll(sleeptime):
                if event & select.POLLIN or event & select.POLLPRI:
                    yield fd
                    continue
                elif event & select.POLLHUP or event & select.POLLERR or event & select.POLLNVAL:
                    spin_prevention = True
                    continue
            if spin_prevention:
                self._prevent_spin()
        except KeyboardInterrupt:
            self._termination('^C received', self.Exit.normal)
            return
        except Exception:
            self._prevent_spin()
            return

    # peer related functions

    def active_peers(self):
        peers = set()
        for key, peer in self._peers.items():
            if not peer.neighbor.passive or peer.proto:
                peers.add(key)
        return peers

    def established_peers(self):
        peers = set()
        for key, peer in self._peers.items():
            if peer.fsm == FSM.ESTABLISHED:
                peers.add(key)
        return peers

    def peers(self):
        return list(self._peers)

    def handle_connection(self, peer_name, connection):
        peer = self._peers.get(peer_name, None)
        if not peer:
            log.critical('could not find referenced peer', 'reactor')
            return
        peer.handle_connection(connection)

    def neighbor(self, peer_name):
        peer = self._peers.get(peer_name, None)
        if not peer:
            log.critical('could not find referenced peer', 'reactor')
            return
        return peer.neighbor

    def neighbor_name(self, peer_name):
        peer = self._peers.get(peer_name, None)
        if not peer:
            log.critical('could not find referenced peer', 'reactor')
            return ""
        return peer.neighbor.name()

    def neighbor_ip(self, peer_name):
        peer = self._peers.get(peer_name, None)
        if not peer:
            log.critical('could not find referenced peer', 'reactor')
            return ""
        return str(peer.neighbor.peer_address)

    def neighbor_cli_data(self, peer_name):
        peer = self._peers.get(peer_name, None)
        if not peer:
            log.critical('could not find referenced peer', 'reactor')
            return ""
        return peer.cli_data()

    def neighor_rib(self, peer_name, rib_name, advertised=False):
        peer = self._peers.get(peer_name, None)
        if not peer:
            log.critical('could not find referenced peer', 'reactor')
            return []
        families = None
        if advertised:
            families = peer.proto.negotiated.families if peer.proto else []
        rib = peer.neighbor.rib.outgoing if rib_name == 'out' else peer.neighbor.rib.incoming
        return list(rib.cached_changes(families))

    def neighbor_rib_resend(self, peer_name):
        peer = self._peers.get(peer_name, None)
        if not peer:
            log.critical('could not find referenced peer', 'reactor')
            return
        peer.neighbor.rib.outgoing.resend(None, peer.neighbor.route_refresh)

    def neighbor_rib_out_withdraw(self, peer_name):
        peer = self._peers.get(peer_name, None)
        if not peer:
            log.critical('could not find referenced peer', 'reactor')
            return
        peer.neighbor.rib.outgoing.withdraw(None, peer.neighbor.route_refresh)

    def neighbor_rib_in_clear(self, peer_name):
        peer = self._peers.get(peer_name, None)
        if not peer:
            log.critical('could not find referenced peer', 'reactor')
            return
        peer.neighbor.rib.incoming.clear()

    # ...

    def _pending_adjribout(self):
        for peer in self.active_peers():
            if self._peers[peer].neighbor.rib.outgoing.pending():
                return True
        return False

    def run(self, validate, root):
        self.daemon.daemonise()

        # Make sure we create processes once we have closed file descriptor
        # unfortunately, this must be done before reading the configuration file
        # so we can not do it with dropped privileges
        self.processes = Processes()

        # we have to read the configuration possibly with root privileges
        # as we need the MD5 information when we bind, and root is needed
        # to bind to a port < 1024

        # this is undesirable as :
        # - handling user generated data as root should be avoided
        # - we may not be able to reload the configuration once the privileges are dropped

        # but I can not see any way to avoid it
        for ip in self._ips:
            if not self.listener.listen_on(ip, None, self._port, None, False, None):
                return self.Exit.listening

        if not self.reload():
            return self.Exit.configuration

        if validate:  # only validate configuration
            log.warning('', 'configuration')
            log.warning('parsed Neighbors, un-templated', 'configuration')
            log.warning('------------------------------', 'configuration')
            log.warning('', 'configuration')
            for key in self._peers:
                log.warning(str(self._peers[key].neighbor), 'configuration')
                log.warning('', 'configuration')
            return self.Exit.validate

        for neighbor in self.configuration.neighbors.values():
            if neighbor.listen:
                if not self.listener.listen_on(
                    neighbor.md5_ip,
                    neighbor.peer_address,
                    neighbor.listen,
                    neighbor.md5_password,
                    neighbor.md5_base64,
                    neighbor.ttl_in,
                ):
                    return self.Exit.listening

        if not self.early_drop:
            self.processes.start(self.configuration.processes)

        if not self.daemon.drop_privileges():
            log.critical(
                'could not drop privileges to \'%s\' refusing to run as root' % self.daemon.user, 'reactor'
            )
            log.critical(
                'set the environmemnt value exabgp.daemon.user to change the unprivileged user', 'reactor'
            )
            return self.Exit.privileges

        if self.early_drop:
            self.processes.start(self.configuration.processes)

        # This is required to make sure we can write in the log location as we now have dropped root privileges
        if not log.restart():
            log.critical('could not setup the logger, aborting', 'reactor')
            return self.Exit.log

        if not self.daemon.savepid():
            return self.Exit.pid

        wait = getenv().tcp.delay
        if wait:
            sleeptime = (wait * 60) - int(time.time()) % (wait * 60)
            log.debug('waiting for %d seconds before connecting' % sleeptime, 'reactor')
            time.sleep(float(sleeptime))

        workers = {}
        peers = set()
        api_fds = []
        ms_sleep = int(self._sleep_time * 1000)

        while True:
            try:
                if self.signal.received:
                    signaled = self.signal.received

                    # report that we received a signal
                    for key in self._peers:
                        if self._peers[key].neighbor.api['signal']:
                            self._peers[key].reactor.processes.signal(self._peers[key].neighbor, self.signal.number)

                    self.signal.rearm()

                    # we always want to exit
                    if signaled == Signal.SHUTDOWN:
                        self.exit_code = self.Exit.normal
                        self.shutdown()
                        break

                    # it does mot matter what we did if we are restarting
                    # as the peers and network stack are replaced by new ones
                    if signaled == Signal.RESTART:
                        self.restart()
                        continue

                    # did we complete the run of updates caused by the last SIGUSR1/SIGUSR2 ?
                    if self._pending_adjribout():
                        continue

                    if signaled == Signal.RELOAD:
                        self.reload()
                        self.processes.start(self.configuration.processes, False)
                        continue

                    if signaled == Signal.FULL_RELOAD:
                        self.reload()
                        self.processes.start(self.configuration.processes, True)
                        continue

                if self.listener.incoming():
                    # check all incoming connection
                    self.asynchronous.schedule(
                        str(uuid.uuid1()), 'checking for new connection(s)', self.listener.new_connections()
                    )

                sleep = ms_sleep

                # do not attempt to listen on closed sockets even if the peer is still here
                for io in list(workers.keys()):
                    if io == -1:
                        self._poller.unregister(io)
                        del workers[io]

                peers = self.active_peers()
                # give a turn to all the peers
                for key in list(peers):
                    peer = self._peers[key]

                    # limit the number of message handling per second
                    if self._rate_limited(key, peer.neighbor.rate_limit):
                        peers.discard(key)
                        continue

                    # handle the peer
                    action = peer.run()

                    # .run() returns an ACTION enum:
                    # * immediate if it wants to be called again
                    # * later if it should be called again but has no work atm
                    # * close if it is finished and is closing down, or restarting
                    if action == ACTION.CLOSE:
                        if key in self._peers:
                            del self._peers[key]
                        peers.discard(key)
                    # we are loosing this peer, not point to schedule more process work
                    elif action == ACTION.LATER:
                        io = peer.socket()
                        if io != -1:
                            self._poller.register(
                                io, select.POLLIN | select.POLLPRI | select.POLLHUP | select.POLLNVAL | select.POLLERR
                            )
                            workers[io] = key
                        # no need to come back to it before a a full cycle
                        peers.discard(key)
                    elif action == ACTION.NOW:
                        sleep = 0

                    if not peers:
                        break

                # read at least on message per process if there is some and parse it
                for service, command in self.processes.received():
                    self.api.text(self, service, command)
                    sleep = 0

                self.asynchronous.run()

                if api_fds != self.processes.fds:
                    for fd in api_fds:
                        if fd == -1:
                            continue
                        if fd not in self.processes.fds:
                            self._poller.unregister(fd)
                    for fd in self.processes.fds:
                        if fd == -1:
                            continue
                        if fd not in api_fds:
                            self._poller.register(
                                fd, select.POLLIN | select.POLLPRI | select.POLLHUP | select.POLLNVAL | select.POLLERR
                            )
                    api_fds = self.processes.fds

                for io in self._wait_for_io(sleep):
                    if io not in api_fds:
                        peers.add(workers[io])

                if self._stopping and not self._peers.keys():
                    self._termination('exiting on peer termination', self.Exit.normal)

            except KeyboardInterrupt:
                self._termination('^C received', self.Exit.normal)
            except SystemExit:
                self._termination('exiting', self.Exit.normal)
            # socket.error is a subclass of IOError (so catch it first)
            except socket.error:
                self._termination('socket error received', self.Exit.socket)
            except IOError:
                self._termination('I/O Error received, most likely ^C during IO', self.Exit.io_error)
            except ProcessError:
                self._termination('Problem when sending message(s) to helper program, stopping', self.Exit.process)
            except select.error:
                self._termination('problem using select, stopping', self.Exit.select)

        return self.exit_code

    def register_peer(self, name, peer):
        self._peers[name] = peer

    def teardown_peer(self, name, code):
        self._peers[name].teardown(code)

    def shutdown(self):
        """Terminate all the current BGP connections"""
        log.critical('performing shutdown', 'reactor')
        if self.listener:
            self.listener.stop()
            self.listener = None
        for key in self._peers.keys():
            self._peers[key].shutdown()
        self.asynchronous.clear()
        self.processes.terminate()
        self.daemon.removepid()
        self._stopping = True

    def reload(self):
        """Reload the configuration and send to the peer the route which changed"""
        log.notice('performing reload of exabgp %s' % version, 'configuration')

        reloaded = self.configuration.reload()

        if not reloaded:
            #
            # Careful the string below is used but the QA code to check for sucess of failure
            log.error('not reloaded, no change found in the configuration', 'configuration')
            # Careful the string above is used but the QA code to check for sucess of failure
            #
            log.error(str(self.configuration.error), 'configuration')
            return False

        for key, peer in self._peers.items():
            if key not in self.configuration.neighbors:
                log.debug('removing peer: %s' % peer.neighbor.name(), 'reactor')
                peer.remove()

        for key, neighbor in self.configuration.neighbors.items():
            # new peer
            if key not in self._peers:
                log.debug('new peer: %s' % neighbor.name(), 'reactor')
                peer = Peer(neighbor, self)
                self._peers[key] = peer
            # modified peer
            elif self._peers[key].neighbor != neighbor:
                log.debug('peer definition change, establishing a new connection for %s' % str(key), 'reactor')
                self._peers[key].reestablish(neighbor)
            # same peer but perhaps not the routes
            else:
                # finding what route changed and sending the delta is not obvious
                log.debug(
                    'peer definition identical, updating peer routes if required for %s' % str(key), 'reactor'
                )
                self._peers[key].reconfigure(neighbor)
            for ip in self._ips:
                if ip.afi == neighbor.peer_address.afi:
                    self.listener.listen_on(
                        ip, neighbor.peer_address, self._port, neighbor.md5_password, neighbor.md5_base64, None
                    )
        log.notice('loaded new configuration successfully', 'reactor')

        return True

    def restart(self):
        """Kill the BGP session and restart it"""
        log.notice('performing restart of exabgp %s' % version, 'reactor')

        # XXX: FIXME: Could return False, in case there is interference with old config...
        reloaded = self.configuration.reload()

        for key in self._peers.keys():
            if key not in self.configuration.neighbors.keys():
                peer = self._peers[key]
                log.debug('removing peer %s' % peer.neighbor.name(), 'reactor')
                self._peers[key].remove()
            else:
                self._peers[key].reestablish()
        self.processes.start(self.configuration.processes, True)

    # def nexthops (self, peers):
    # 	return dict((peer,self._peers[peer].neighbor.local_address) for peer in peers)


1			# encoding: utf-8
2			"""
3			reactor/loop.py
4
5			Created by Thomas Mangin on 2012-06-10.
6			Copyright (c) 2009-2017 Exa Networks. All rights reserved.
7			License: 3-clause BSD. (See the COPYRIGHT file)
8			"""
9
10			import time
11			import uuid
12			import select
13			import socket
14
15			from exabgp.reactor.daemon import Daemon
16			from exabgp.reactor.listener import Listener
17			from exabgp.reactor.api.processes import Processes
18			from exabgp.reactor.api.processes import ProcessError
19			from exabgp.reactor.peer import Peer
20			from exabgp.reactor.peer import ACTION
21			from exabgp.reactor.asynchronous import ASYNC
22			from exabgp.reactor.interrupt import Signal
23
24			from exabgp.reactor.api import API
25			from exabgp.configuration.configuration import Configuration
26			from exabgp.environment import getenv
27
28			from exabgp.bgp.fsm import FSM
29
30			from exabgp.version import version
31			from exabgp.logger import log
32
33
34			class Reactor(object):
35			class Exit(object):
36			normal = 0
37			validate = 0
38			listening = 1
39			configuration = 1
40			privileges = 1
41			log = 1
42			pid = 1
43			socket = 1
44			io_error = 1
45			process = 1
46			select = 1
47			unknown = 1
48
49			# [hex(ord(c)) for c in os.popen('clear').read()]
50			clear = b''.join(bytes([int(c, 16)]) for c in ['0x1b', '0x5b', '0x48', '0x1b', '0x5b', '0x32', '0x4a'])
51
52			def __init__(self, configurations):
53			self._ips = getenv().tcp.bind
54			self._port = getenv().tcp.port
55			self._stopping = getenv().tcp.once
56			self.exit_code = self.Exit.unknown
57
58			self.max_loop_time = getenv().reactor.speed
59			self._sleep_time = self.max_loop_time / 100
60			self._busyspin = {}
61			self._ratelimit = {}
62			self.early_drop = getenv().daemon.drop
63
64			self.processes = None
65
66			self.configuration = Configuration(configurations)
67			self.asynchronous = ASYNC()
68			self.signal = Signal()
69			self.daemon = Daemon(self)
70			self.listener = Listener(self)
71			self.api = API(self)
72
73			self._peers = {}
74
75			self._saved_pid = False
76			self._poller = select.poll()
77
78			def _termination(self, reason, exit_code):
79			self.exit_code = exit_code
80			self.signal.received = Signal.SHUTDOWN
81			log.critical(reason, 'reactor')
82
83			def _prevent_spin(self):
84			second = int(time.time())
85			if not second in self._busyspin:
86			self._busyspin = {second: 0}
87			self._busyspin[second] += 1
88			if self._busyspin[second] > self.max_loop_time:
89			time.sleep(self._sleep_time)
90			return True
91			return False
92
93			def _rate_limited(self, peer, rate):
94			if rate <= 0:
95			return False
96			second = int(time.time())
97			ratelimit = self._ratelimit.get(peer, {})
98			if not second in ratelimit:
99			self._ratelimit[peer] = {second: rate - 1}
100			return False
101			if self._ratelimit[peer][second] > 0:
102			self._ratelimit[peer][second] -= 1
103			return False
104			return True
105
106			def _wait_for_io(self, sleeptime):
107			spin_prevention = False
108			try:
109			for fd, event in self._poller.poll(sleeptime):
110			if event & select.POLLIN or event & select.POLLPRI:
111			yield fd
112			continue
113			elif event & select.POLLHUP or event & select.POLLERR or event & select.POLLNVAL:
114			spin_prevention = True
115			continue
116			if spin_prevention:
117			self._prevent_spin()
118			except KeyboardInterrupt:
119			self._termination('^C received', self.Exit.normal)
120			return
121			except Exception:
122			self._prevent_spin()
123			return
124
125			# peer related functions
126
127			def active_peers(self):
128			peers = set()
129			for key, peer in self._peers.items():
130			if not peer.neighbor.passive or peer.proto:
131			peers.add(key)
132			return peers
133
134			def established_peers(self):
135			peers = set()
136			for key, peer in self._peers.items():
137			if peer.fsm == FSM.ESTABLISHED:
138			peers.add(key)
139			return peers
140
141			def peers(self):
142			return list(self._peers)
143
144			def handle_connection(self, peer_name, connection):
145			peer = self._peers.get(peer_name, None)
146			if not peer:
147			log.critical('could not find referenced peer', 'reactor')
148			return
149			peer.handle_connection(connection)
150
151			def neighbor(self, peer_name):
152			peer = self._peers.get(peer_name, None)
153			if not peer:
154			log.critical('could not find referenced peer', 'reactor')
155			return
156			return peer.neighbor
157
158			def neighbor_name(self, peer_name):
159			peer = self._peers.get(peer_name, None)
160			if not peer:
161			log.critical('could not find referenced peer', 'reactor')
162			return ""
163			return peer.neighbor.name()
164
165			def neighbor_ip(self, peer_name):
166			peer = self._peers.get(peer_name, None)
167			if not peer:
168			log.critical('could not find referenced peer', 'reactor')
169			return ""
170			return str(peer.neighbor.peer_address)
171
172			def neighbor_cli_data(self, peer_name):
173			peer = self._peers.get(peer_name, None)
174			if not peer:
175			log.critical('could not find referenced peer', 'reactor')
176			return ""
177			return peer.cli_data()
178
179			def neighor_rib(self, peer_name, rib_name, advertised=False):
180			peer = self._peers.get(peer_name, None)
181			if not peer:
182			log.critical('could not find referenced peer', 'reactor')
183			return []
184			families = None
185			if advertised:
186			families = peer.proto.negotiated.families if peer.proto else []
187			rib = peer.neighbor.rib.outgoing if rib_name == 'out' else peer.neighbor.rib.incoming
188			return list(rib.cached_changes(families))
189
190			def neighbor_rib_resend(self, peer_name):
191			peer = self._peers.get(peer_name, None)
192			if not peer:
193			log.critical('could not find referenced peer', 'reactor')
194			return
195			peer.neighbor.rib.outgoing.resend(None, peer.neighbor.route_refresh)
196
197			def neighbor_rib_out_withdraw(self, peer_name):
198			peer = self._peers.get(peer_name, None)
199			if not peer:
200			log.critical('could not find referenced peer', 'reactor')
201			return
202			peer.neighbor.rib.outgoing.withdraw(None, peer.neighbor.route_refresh)
203
204			def neighbor_rib_in_clear(self, peer_name):
205			peer = self._peers.get(peer_name, None)
206			if not peer:
207			log.critical('could not find referenced peer', 'reactor')
208			return
209			peer.neighbor.rib.incoming.clear()
210
211			# ...
212
213			def _pending_adjribout(self):
214			for peer in self.active_peers():
215			if self._peers[peer].neighbor.rib.outgoing.pending():
216			return True
217			return False
218
219			def run(self, validate, root):
220			self.daemon.daemonise()
221
222			# Make sure we create processes once we have closed file descriptor
223			# unfortunately, this must be done before reading the configuration file
224			# so we can not do it with dropped privileges
225			self.processes = Processes()
226
227			# we have to read the configuration possibly with root privileges
228			# as we need the MD5 information when we bind, and root is needed
229			# to bind to a port < 1024
230
231			# this is undesirable as :
232			# - handling user generated data as root should be avoided
233			# - we may not be able to reload the configuration once the privileges are dropped
234
235			# but I can not see any way to avoid it
236			for ip in self._ips:
237			if not self.listener.listen_on(ip, None, self._port, None, False, None):
238			return self.Exit.listening
239
240			if not self.reload():
241			return self.Exit.configuration
242
243			if validate: # only validate configuration
244			log.warning('', 'configuration')
245			log.warning('parsed Neighbors, un-templated', 'configuration')
246			log.warning('------------------------------', 'configuration')
247			log.warning('', 'configuration')
248			for key in self._peers:
249			log.warning(str(self._peers[key].neighbor), 'configuration')
250			log.warning('', 'configuration')
251			return self.Exit.validate
252
253			for neighbor in self.configuration.neighbors.values():
254			if neighbor.listen:
255			if not self.listener.listen_on(
256			neighbor.md5_ip,
257			neighbor.peer_address,
258			neighbor.listen,
259			neighbor.md5_password,
260			neighbor.md5_base64,
261			neighbor.ttl_in,
262			):
263			return self.Exit.listening
264
265			if not self.early_drop:
266			self.processes.start(self.configuration.processes)
267
268			if not self.daemon.drop_privileges():
269			log.critical(
270			'could not drop privileges to \'%s\' refusing to run as root' % self.daemon.user, 'reactor'
271			)
272			log.critical(
273			'set the environmemnt value exabgp.daemon.user to change the unprivileged user', 'reactor'
274			)
275			return self.Exit.privileges
276
277			if self.early_drop:
278			self.processes.start(self.configuration.processes)
279
280			# This is required to make sure we can write in the log location as we now have dropped root privileges
281			if not log.restart():
282			log.critical('could not setup the logger, aborting', 'reactor')
283			return self.Exit.log
284
285			if not self.daemon.savepid():
286			return self.Exit.pid
287
288			wait = getenv().tcp.delay
289			if wait:
290			sleeptime = (wait * 60) - int(time.time()) % (wait * 60)
291			log.debug('waiting for %d seconds before connecting' % sleeptime, 'reactor')
292			time.sleep(float(sleeptime))
293
294			workers = {}
295			peers = set()
296			api_fds = []
297			ms_sleep = int(self._sleep_time * 1000)
298
299			while True:
300			try:
301			if self.signal.received:
302			signaled = self.signal.received
303
304			# report that we received a signal
305			for key in self._peers:
306			if self._peers[key].neighbor.api['signal']:
307			self._peers[key].reactor.processes.signal(self._peers[key].neighbor, self.signal.number)
308
309			self.signal.rearm()
310
311			# we always want to exit
312			if signaled == Signal.SHUTDOWN:
313			self.exit_code = self.Exit.normal
314			self.shutdown()
315			break
316
317			# it does mot matter what we did if we are restarting
318			# as the peers and network stack are replaced by new ones
319			if signaled == Signal.RESTART:
320			self.restart()
321			continue
322
323			# did we complete the run of updates caused by the last SIGUSR1/SIGUSR2 ?
324			if self._pending_adjribout():
325			continue
326
327			if signaled == Signal.RELOAD:
328			self.reload()
329			self.processes.start(self.configuration.processes, False)
330			continue
331
332			if signaled == Signal.FULL_RELOAD:
333			self.reload()
334			self.processes.start(self.configuration.processes, True)
335			continue
336
337			if self.listener.incoming():
338			# check all incoming connection
339			self.asynchronous.schedule(
340			str(uuid.uuid1()), 'checking for new connection(s)', self.listener.new_connections()
341			)
342
343			sleep = ms_sleep
344
345			# do not attempt to listen on closed sockets even if the peer is still here
346			for io in list(workers.keys()):
347			if io == -1:
348			self._poller.unregister(io)
349			del workers[io]
350
351			peers = self.active_peers()
352			# give a turn to all the peers
353			for key in list(peers):
354			peer = self._peers[key]
355
356			# limit the number of message handling per second
357			if self._rate_limited(key, peer.neighbor.rate_limit):
358			peers.discard(key)
359			continue
360
361			# handle the peer
362			action = peer.run()
363
364			# .run() returns an ACTION enum:
365			# * immediate if it wants to be called again
366			# * later if it should be called again but has no work atm
367			# * close if it is finished and is closing down, or restarting
368			if action == ACTION.CLOSE:
369			if key in self._peers:
370			del self._peers[key]
371			peers.discard(key)
372			# we are loosing this peer, not point to schedule more process work
373			elif action == ACTION.LATER:
374			io = peer.socket()
375			if io != -1:
376			self._poller.register(
377			io, select.POLLIN \| select.POLLPRI \| select.POLLHUP \| select.POLLNVAL \| select.POLLERR
378			)
379			workers[io] = key
380			# no need to come back to it before a a full cycle
381			peers.discard(key)
382			elif action == ACTION.NOW:
383			sleep = 0
384
385			if not peers:
386			break
387
388			# read at least on message per process if there is some and parse it
389			for service, command in self.processes.received():
390			self.api.text(self, service, command)
391			sleep = 0
392
393			self.asynchronous.run()
394
395			if api_fds != self.processes.fds:
396			for fd in api_fds:
397			if fd == -1:
398			continue
399			if fd not in self.processes.fds:
400			self._poller.unregister(fd)
401			for fd in self.processes.fds:
402			if fd == -1:
403			continue
404			if fd not in api_fds:
405			self._poller.register(
406			fd, select.POLLIN \| select.POLLPRI \| select.POLLHUP \| select.POLLNVAL \| select.POLLERR
407			)
408			api_fds = self.processes.fds
409
410			for io in self._wait_for_io(sleep):
411			if io not in api_fds:
412			peers.add(workers[io])
413
414			if self._stopping and not self._peers.keys():
415			self._termination('exiting on peer termination', self.Exit.normal)
416
417			except KeyboardInterrupt:
418			self._termination('^C received', self.Exit.normal)
419			except SystemExit:
420			self._termination('exiting', self.Exit.normal)
421			# socket.error is a subclass of IOError (so catch it first)
422			except socket.error:
423			self._termination('socket error received', self.Exit.socket)
424			except IOError:
425			self._termination('I/O Error received, most likely ^C during IO', self.Exit.io_error)
426			except ProcessError:
427			self._termination('Problem when sending message(s) to helper program, stopping', self.Exit.process)
428			except select.error:
429			self._termination('problem using select, stopping', self.Exit.select)
430
431			return self.exit_code
432
433			def register_peer(self, name, peer):
434			self._peers[name] = peer
435
436			def teardown_peer(self, name, code):
437			self._peers[name].teardown(code)
438
439			def shutdown(self):
440			"""Terminate all the current BGP connections"""
441			log.critical('performing shutdown', 'reactor')
442			if self.listener:
443			self.listener.stop()
444			self.listener = None
445			for key in self._peers.keys():
446			self._peers[key].shutdown()
447			self.asynchronous.clear()
448			self.processes.terminate()
449			self.daemon.removepid()
450			self._stopping = True
451
452			def reload(self):
453			"""Reload the configuration and send to the peer the route which changed"""
454			log.notice('performing reload of exabgp %s' % version, 'configuration')
455
456			reloaded = self.configuration.reload()
457
458			if not reloaded:
459			#
460			# Careful the string below is used but the QA code to check for sucess of failure
461			log.error('not reloaded, no change found in the configuration', 'configuration')
462			# Careful the string above is used but the QA code to check for sucess of failure
463			#
464			log.error(str(self.configuration.error), 'configuration')
465			return False
466
467			for key, peer in self._peers.items():
468			if key not in self.configuration.neighbors:
469			log.debug('removing peer: %s' % peer.neighbor.name(), 'reactor')
470			peer.remove()
471
472			for key, neighbor in self.configuration.neighbors.items():
473			# new peer
474			if key not in self._peers:
475			log.debug('new peer: %s' % neighbor.name(), 'reactor')
476			peer = Peer(neighbor, self)
477			self._peers[key] = peer
478			# modified peer
479			elif self._peers[key].neighbor != neighbor:
480			log.debug('peer definition change, establishing a new connection for %s' % str(key), 'reactor')
481			self._peers[key].reestablish(neighbor)
482			# same peer but perhaps not the routes
483			else:
484			# finding what route changed and sending the delta is not obvious
485			log.debug(
486			'peer definition identical, updating peer routes if required for %s' % str(key), 'reactor'
487			)
488			self._peers[key].reconfigure(neighbor)
489			for ip in self._ips:
490			if ip.afi == neighbor.peer_address.afi:
491			self.listener.listen_on(
492			ip, neighbor.peer_address, self._port, neighbor.md5_password, neighbor.md5_base64, None
493			)
494			log.notice('loaded new configuration successfully', 'reactor')
495
496			return True
497
498			def restart(self):
499			"""Kill the BGP session and restart it"""
500			log.notice('performing restart of exabgp %s' % version, 'reactor')
501
502			# XXX: FIXME: Could return False, in case there is interference with old config...
503			reloaded = self.configuration.reload()
504
505			for key in self._peers.keys():
506			if key not in self.configuration.neighbors.keys():
507			peer = self._peers[key]
508			log.debug('removing peer %s' % peer.neighbor.name(), 'reactor')
509			self._peers[key].remove()
510			else:
511			self._peers[key].reestablish()
512			self.processes.start(self.configuration.processes, True)
513
514			# def nexthops (self, peers):
515			# return dict((peer,self._peers[peer].neighbor.local_address) for peer in peers)
516

Exa-Networks / exabgp

Push — master ( ea37f3...9aacac )

exabgp.reactor.loop.Reactor.neighbor_cli_data() A

Complexity

Size

Duplication

Importance

Duplication Side-by-Side

Filter issues like