diff options
Diffstat (limited to 'lib/python2.7/site-packages/Twisted-12.2.0-py2.7-linux-x86_64.egg/twisted/names/srvconnect.py')
| -rwxr-xr-x | lib/python2.7/site-packages/Twisted-12.2.0-py2.7-linux-x86_64.egg/twisted/names/srvconnect.py | 211 |
1 files changed, 0 insertions, 211 deletions
diff --git a/lib/python2.7/site-packages/Twisted-12.2.0-py2.7-linux-x86_64.egg/twisted/names/srvconnect.py b/lib/python2.7/site-packages/Twisted-12.2.0-py2.7-linux-x86_64.egg/twisted/names/srvconnect.py deleted file mode 100755 index 34434db6..00000000 --- a/lib/python2.7/site-packages/Twisted-12.2.0-py2.7-linux-x86_64.egg/twisted/names/srvconnect.py +++ /dev/null @@ -1,211 +0,0 @@ -# -*- test-case-name: twisted.names.test.test_srvconnect -*- -# Copyright (c) Twisted Matrix Laboratories. -# See LICENSE for details. - -import random - -from zope.interface import implements - -from twisted.internet import error, interfaces - -from twisted.names import client, dns -from twisted.names.error import DNSNameError -from twisted.python.compat import reduce - -class _SRVConnector_ClientFactoryWrapper: - def __init__(self, connector, wrappedFactory): - self.__connector = connector - self.__wrappedFactory = wrappedFactory - - def startedConnecting(self, connector): - self.__wrappedFactory.startedConnecting(self.__connector) - - def clientConnectionFailed(self, connector, reason): - self.__connector.connectionFailed(reason) - - def clientConnectionLost(self, connector, reason): - self.__connector.connectionLost(reason) - - def __getattr__(self, key): - return getattr(self.__wrappedFactory, key) - -class SRVConnector: - """A connector that looks up DNS SRV records. See RFC2782.""" - - implements(interfaces.IConnector) - - stopAfterDNS=0 - - def __init__(self, reactor, service, domain, factory, - protocol='tcp', connectFuncName='connectTCP', - connectFuncArgs=(), - connectFuncKwArgs={}, - defaultPort=None, - ): - """ - @ivar defaultPort: Optional default port number to be used when SRV - lookup fails and the service name is unknown. This should be the - port number associated with the service name as defined by the IANA - registry. - @type defaultPort: C{int} - """ - self.reactor = reactor - self.service = service - self.domain = domain - self.factory = factory - - self.protocol = protocol - self.connectFuncName = connectFuncName - self.connectFuncArgs = connectFuncArgs - self.connectFuncKwArgs = connectFuncKwArgs - self._defaultPort = defaultPort - - self.connector = None - self.servers = None - self.orderedServers = None # list of servers already used in this round - - def connect(self): - """Start connection to remote server.""" - self.factory.doStart() - self.factory.startedConnecting(self) - - if not self.servers: - if self.domain is None: - self.connectionFailed(error.DNSLookupError("Domain is not defined.")) - return - d = client.lookupService('_%s._%s.%s' % (self.service, - self.protocol, - self.domain)) - d.addCallbacks(self._cbGotServers, self._ebGotServers) - d.addCallback(lambda x, self=self: self._reallyConnect()) - if self._defaultPort: - d.addErrback(self._ebServiceUnknown) - d.addErrback(self.connectionFailed) - elif self.connector is None: - self._reallyConnect() - else: - self.connector.connect() - - def _ebGotServers(self, failure): - failure.trap(DNSNameError) - - # Some DNS servers reply with NXDOMAIN when in fact there are - # just no SRV records for that domain. Act as if we just got an - # empty response and use fallback. - - self.servers = [] - self.orderedServers = [] - - def _cbGotServers(self, (answers, auth, add)): - if len(answers) == 1 and answers[0].type == dns.SRV \ - and answers[0].payload \ - and answers[0].payload.target == dns.Name('.'): - # decidedly not available - raise error.DNSLookupError("Service %s not available for domain %s." - % (repr(self.service), repr(self.domain))) - - self.servers = [] - self.orderedServers = [] - for a in answers: - if a.type != dns.SRV or not a.payload: - continue - - self.orderedServers.append((a.payload.priority, a.payload.weight, - str(a.payload.target), a.payload.port)) - - def _ebServiceUnknown(self, failure): - """ - Connect to the default port when the service name is unknown. - - If no SRV records were found, the service name will be passed as the - port. If resolving the name fails with - L{error.ServiceNameUnknownError}, a final attempt is done using the - default port. - """ - failure.trap(error.ServiceNameUnknownError) - self.servers = [(0, 0, self.domain, self._defaultPort)] - self.orderedServers = [] - self.connect() - - def _serverCmp(self, a, b): - if a[0]!=b[0]: - return cmp(a[0], b[0]) - else: - return cmp(a[1], b[1]) - - def pickServer(self): - assert self.servers is not None - assert self.orderedServers is not None - - if not self.servers and not self.orderedServers: - # no SRV record, fall back.. - return self.domain, self.service - - if not self.servers and self.orderedServers: - # start new round - self.servers = self.orderedServers - self.orderedServers = [] - - assert self.servers - - self.servers.sort(self._serverCmp) - minPriority=self.servers[0][0] - - weightIndex = zip(xrange(len(self.servers)), [x[1] for x in self.servers - if x[0]==minPriority]) - weightSum = reduce(lambda x, y: (None, x[1]+y[1]), weightIndex, (None, 0))[1] - rand = random.randint(0, weightSum) - - for index, weight in weightIndex: - weightSum -= weight - if weightSum <= 0: - chosen = self.servers[index] - del self.servers[index] - self.orderedServers.append(chosen) - - p, w, host, port = chosen - return host, port - - raise RuntimeError, 'Impossible %s pickServer result.' % self.__class__.__name__ - - def _reallyConnect(self): - if self.stopAfterDNS: - self.stopAfterDNS=0 - return - - self.host, self.port = self.pickServer() - assert self.host is not None, 'Must have a host to connect to.' - assert self.port is not None, 'Must have a port to connect to.' - - connectFunc = getattr(self.reactor, self.connectFuncName) - self.connector=connectFunc( - self.host, self.port, - _SRVConnector_ClientFactoryWrapper(self, self.factory), - *self.connectFuncArgs, **self.connectFuncKwArgs) - - def stopConnecting(self): - """Stop attempting to connect.""" - if self.connector: - self.connector.stopConnecting() - else: - self.stopAfterDNS=1 - - def disconnect(self): - """Disconnect whatever our are state is.""" - if self.connector is not None: - self.connector.disconnect() - else: - self.stopConnecting() - - def getDestination(self): - assert self.connector - return self.connector.getDestination() - - def connectionFailed(self, reason): - self.factory.clientConnectionFailed(self, reason) - self.factory.doStop() - - def connectionLost(self, reason): - self.factory.clientConnectionLost(self, reason) - self.factory.doStop() - |