import re, time, sha from base64 import b32decode from zope.interface import implements from twisted.application import service from foolscap import Referenceable from allmydata import node from allmydata.interfaces import RIIntroducerPublisherAndSubscriberService, \ RIIntroducerSubscriberClient, IIntroducerClient from allmydata.util import log, idlib class IntroducerNode(node.Node): PORTNUMFILE = "introducer.port" NODETYPE = "introducer" def __init__(self, basedir="."): node.Node.__init__(self, basedir) self.init_introducer() def init_introducer(self): introducerservice = IntroducerService(self.basedir) self.add_service(introducerservice) d = self.when_tub_ready() def _publish(res): self.introducer_url = self.tub.registerReference(introducerservice, "introducer") self.log(" introducer is at %s" % self.introducer_url) self.write_config("introducer.furl", self.introducer_url + "\n") d.addCallback(_publish) d.addErrback(log.err, facility="tahoe.init", level=log.BAD) class IntroducerService(service.MultiService, Referenceable): implements(RIIntroducerPublisherAndSubscriberService) name = "introducer" def __init__(self, basedir="."): service.MultiService.__init__(self) self.introducer_url = None self._announcements = set() self._subscribers = {} def log(self, *args, **kwargs): if "facility" not in kwargs: kwargs["facility"] = "tahoe.introducer" return log.msg(*args, **kwargs) def remote_publish(self, announcement): self.log("introducer: announcement published: %s" % (announcement,) ) (furl, service_name, ri_name, nickname, ver, oldest) = announcement if announcement in self._announcements: self.log("but we already knew it, ignoring", level=log.NOISY) return self._announcements.add(announcement) for s in self._subscribers.get(service_name, []): s.callRemote("announce", set([announcement])) def remote_subscribe(self, subscriber, service_name): self.log("introducer: subscription[%s] request at %s" % (service_name, subscriber)) if service_name not in self._subscribers: self._subscribers[service_name] = set() subscribers = self._subscribers[service_name] if subscriber in subscribers: self.log("but they're already subscribed, ignoring", level=log.UNUSUAL) return subscribers.add(subscriber) def _remove(): self.log("introducer: unsubscribing[%s] %s" % (service_name, subscriber)) subscribers.remove(subscriber) subscriber.notifyOnDisconnect(_remove) announcements = set( [ a for a in self._announcements if a[1] == service_name ] ) d = subscriber.callRemote("announce", announcements) d.addErrback(log.err, facility="tahoe.introducer", level=log.UNUSUAL) class RemoteServiceConnector: """I hold information about a peer service that we want to connect to. If we are connected, I hold the RemoteReference, the peer's address, and the peer's version information. I remember information about when we were last connected to the peer too, even if we aren't currently connected. @ivar announcement_time: when we first heard about this service @ivar last_connect_time: when we last established a connection @ivar last_loss_time: when we last lost a connection @ivar version: the peer's version, from the most recent announcement @ivar oldest_supported: the peer's oldest supported version, same @ivar nickname: the peer's self-reported nickname, same @ivar rref: the RemoteReference, if connected, otherwise None @ivar remote_host: the IAddress, if connected, otherwise None """ def __init__(self, announcement, tub, ic): self._tub = tub self._announcement = announcement self._ic = ic (furl, service_name, ri_name, nickname, ver, oldest) = announcement self._furl = furl m = re.match(r'pb://(\w+)@', furl) assert m self._nodeid = b32decode(m.group(1).upper()) self._nodeid_s = idlib.shortnodeid_b2a(self._nodeid) self._index = (self._nodeid, service_name) self.service_name = service_name self.log("attempting to connect to %s" % self._nodeid_s) self.announcement_time = time.time() self.last_loss_time = None self.rref = None self.remote_host = None self.last_connect_time = None self.version = ver self.oldest_supported = oldest self.nickname = nickname def log(self, *args, **kwargs): return self._ic.log(*args, **kwargs) def get_index(self): return self._index def startConnecting(self): self._reconnector = self._tub.connectTo(self._furl, self._got_service) def stopConnecting(self): self._reconnector.stopConnecting() def _got_service(self, rref): self.last_connect_time = time.time() self.remote_host = rref.tracker.broker.transport.getPeer() self.rref = rref self.log("connected to %s" % self._nodeid_s) self._ic.add_connection(self._nodeid, self.service_name, rref) rref.notifyOnDisconnect(self._lost, rref) def _lost(self, rref): self.log("lost connection to %s" % self._nodeid_s) self.last_loss_time = time.time() self.rref = None self.remote_host = None self._ic.remove_connection(self._nodeid, self.service_name, rref) class IntroducerClient(service.Service, Referenceable): implements(RIIntroducerSubscriberClient, IIntroducerClient) def __init__(self, tub, introducer_furl, nickname, my_version, oldest_supported): self._tub = tub self.introducer_furl = introducer_furl self._nickname = nickname self._my_version = my_version self._oldest_supported = oldest_supported self._published_announcements = set() self._publisher = None self._connected = False self._subscribed_service_names = set() self._subscriptions = set() # requests we've actually sent self._received_announcements = set() # TODO: this set will grow without bound, until the node is restarted # we only accept one announcement per (peerid+service_name) pair. # This insures that an upgraded host replace their previous # announcement. It also means that each peer must have their own Tub # (no sharing), which is slightly weird but consistent with the rest # of the Tahoe codebase. self._connectors = {} # k: (peerid+svcname), v: RemoteServiceConnector # self._connections is a set of (peerid, service_name, rref) tuples self._connections = set() self.counter = 0 # incremented each time we change state, for tests self.encoding_parameters = None def startService(self): service.Service.startService(self) rc = self._tub.connectTo(self.introducer_furl, self._got_introducer) self._introducer_reconnector = rc def connect_failed(failure): self.log("Initial Introducer connection failed: perhaps it's down", level=log.WEIRD, failure=failure) d = self._tub.getReference(self.introducer_furl) d.addErrback(connect_failed) def _got_introducer(self, publisher): self.log("connected to introducer") self._connected = True self._publisher = publisher publisher.notifyOnDisconnect(self._disconnected) self._maybe_publish() self._maybe_subscribe() def _disconnected(self): self.log("bummer, we've lost our connection to the introducer") self._connected = False self._publisher = None self._subscriptions.clear() def stopService(self): service.Service.stopService(self) self._introducer_reconnector.stopConnecting() for rsc in self._connectors.itervalues(): rsc.stopConnecting() def log(self, *args, **kwargs): if "facility" not in kwargs: kwargs["facility"] = "tahoe.introducer" return log.msg(*args, **kwargs) def publish(self, furl, service_name, remoteinterface_name): ann = (furl, service_name, remoteinterface_name, self._nickname, self._my_version, self._oldest_supported) self._published_announcements.add(ann) self._maybe_publish() def subscribe_to(self, service_name): self._subscribed_service_names.add(service_name) self._maybe_subscribe() def _maybe_subscribe(self): if not self._publisher: self.log("want to subscribe, but no introducer yet", level=log.NOISY) return for service_name in self._subscribed_service_names: if service_name not in self._subscriptions: # there is a race here, but the subscription desk ignores # duplicate requests. self._subscriptions.add(service_name) d = self._publisher.callRemote("subscribe", self, service_name) d.addErrback(log.err, facility="tahoe.introducer", level=log.WEIRD) def _maybe_publish(self): if not self._publisher: self.log("want to publish, but no introducer yet", level=log.NOISY) return # this re-publishes everything. The Introducer ignores duplicates for ann in self._published_announcements: d = self._publisher.callRemote("publish", ann) d.addErrback(log.err, facility="tahoe.introducer", level=log.WEIRD) def remote_announce(self, announcements): for ann in announcements: self.log("received %d announcements" % len(announcements)) (furl, service_name, ri_name, nickname, ver, oldest) = ann if service_name not in self._subscribed_service_names: self.log("announcement for a service we don't care about [%s]" % (service_name,), level=log.WEIRD) continue if ann in self._received_announcements: self.log("ignoring old announcement: %s" % (ann,), level=log.NOISY) continue self.log("new announcement[%s]: %s" % (service_name, ann)) self._received_announcements.add(ann) self._new_announcement(ann) def _new_announcement(self, announcement): # this will only be called for new announcements rsc = RemoteServiceConnector(announcement, self._tub, self) index = rsc.get_index() if index in self._connectors: self._connectors[index].stopConnecting() self._connectors[index] = rsc rsc.startConnecting() def add_connection(self, nodeid, service_name, rref): self._connections.add( (nodeid, service_name, rref) ) self.counter += 1 def remove_connection(self, nodeid, service_name, rref): self._connections.discard( (nodeid, service_name, rref) ) self.counter += 1 def get_all_connections(self): return frozenset(self._connections) def get_all_connectors(self): return self._connectors.copy() def get_all_peerids(self): return frozenset([peerid for (peerid, service_name, rref) in self._connections]) def get_all_connections_for(self, service_name): return frozenset([c for c in self._connections if c[1] == service_name]) def get_permuted_peers(self, service_name, key): """Return an ordered list of (peerid, rref) tuples.""" results = [] for (c_peerid, c_service_name, rref) in self._connections: assert isinstance(c_peerid, str) if c_service_name != service_name: continue permuted = sha.new(key + c_peerid).digest() results.append((permuted, c_peerid, rref)) results.sort(lambda a,b: cmp(a[0], b[0])) return [ (r[1], r[2]) for r in results ] def remote_set_encoding_parameters(self, parameters): self.encoding_parameters = parameters def connected_to_introducer(self): return self._connected def debug_disconnect_from_peerid(self, victim_nodeid): # for unit tests: locate and sever all connections to the given # peerid. for (nodeid, service_name, rref) in self._connections: if nodeid == victim_nodeid: rref.tracker.broker.transport.loseConnection()