Example #1
0
 def loadActorSource(self, fname):
     self._LOADFAILED = None
     loadLimit = ExpiryTime(MAX_LOAD_SOURCE_DELAY)
     f = fname if hasattr(fname, 'read') else open(fname, 'rb')
     try:
         d = f.read()
         import hashlib
         hval = hashlib.md5(d).hexdigest()
         self.transport.scheduleTransmit(
             None,
             TransmitIntent(
                 self.adminAddr,
                 ValidateSource(
                     hval, d,
                     getattr(
                         f, 'name',
                         str(fname) if hasattr(fname, 'read') else fname)),
                 onError=self._loadReqFailed))
         while not loadLimit.expired():
             if not self.transport.run(TransmitOnly, loadLimit.remaining()):
                 break  # all transmits completed
         if self._LOADFAILED or loadLimit.expired():
             raise ActorSystemFailure('Load source failed due to ' + (
                 'failure response (%s)' %
                 self._LOADFAILED if self._LOADFAILED else 'timeout (%s)' %
                 str(loadLimit)))
         return hval
     finally:
         f.close()
Example #2
0
 def updateCapability(self, capabilityName, capabilityValue=None):
     self._updCAPFAILED = False
     attemptLimit = ExpiryTime(MAX_CAPABILITY_UPDATE_DELAY)
     self.transport.scheduleTransmit(
         None,
         TransmitIntent(self.adminAddr,
                        CapabilityUpdate(capabilityName, capabilityValue),
                        onError=self._updateCapsFailed))
     while not attemptLimit.expired():
         if not self.transport.run(TransmitOnly, attemptLimit.remaining()):
             break  # all transmits completed
     if self._updCAPFAILED or attemptLimit.expired():
         raise ActorSystemFailure(
             "Could not update Actor System Admin capabilities.")
Example #3
0
 def unloadActorSource(self, sourceHash):
     self._LOADFAILED = None
     loadLimit = ExpiryTime(MAX_LOAD_SOURCE_DELAY)
     self.transport.scheduleTransmit(
         None,
         TransmitIntent(self.adminAddr,
                        ValidateSource(sourceHash, None),
                        onError=self._loadReqFailed))
     while not loadLimit.expired():
         if not self.transport.run(TransmitOnly, loadLimit.remaining()):
             break  # all transmits completed
     if self._LOADFAILED or loadLimit.expired():
         raise ActorSystemFailure('Unload source failed due to ' + (
             'failure response' if self._LOADFAILED else 'timeout (%s)' %
             str(loadLimit)))
Example #4
0
 def tell(self, anActor, msg):
     attemptLimit = ExpiryTime(MAX_TELL_PERIOD)
     # transport may not use sockets, but this helps error handling
     # in case it does.
     import socket
     for attempt in range(5000):
         try:
             txwatch = self._tx_to_actor(anActor, msg)
             while not attemptLimit.expired():
                 if not self._run_transport(attemptLimit.remaining(),
                                            txonly=True):
                     # all transmits completed
                     return
                 if txwatch.failed:
                     raise ActorSystemFailure(
                         'Error sending to %s: %s' % (str(anActor),
                                                      str(txwatch.failure)))
             raise ActorSystemRequestTimeout(
                 'Unable to send to %s within %s' %
                 (str(anActor), str(MAX_CAPABILITY_UPDATE_DELAY)))
         except socket.error as ex:
             import errno
             if errno.EMFILE == ex.errno:
                 import time
                 time.sleep(0.1)
             else:
                 raise
Example #5
0
 def shutdown(self):
     thesplog('ActorSystem shutdown requested.', level=logging.INFO)
     time_to_quit = ExpiryTime(MAX_SYSTEM_SHUTDOWN_DELAY)
     self.transport.scheduleTransmit(
         None,
         TransmitIntent(self.adminAddr,
                        SystemShutdown(),
                        onError=self._shutdownSendFailed))
     while not time_to_quit.expired():
         response = self.transport.run(None, time_to_quit.remaining())
         if getattr(self, '_TASF', False):
             thesplog(
                 'Could not send shutdown request to Admin'
                 '; aborting but not necessarily stopped',
                 level=logging.WARNING)
             return
         if response:
             if isinstance(response.message, SystemShutdownCompleted):
                 break
             else:
                 thesplog('Expected shutdown completed message, got: %s',
                          response.message,
                          level=logging.WARNING)
         else:
             thesplog(
                 'No response to Admin shutdown request; Actor system not completely shutdown',
                 level=logging.ERROR)
     thesplog('ActorSystem shutdown complete.')
Example #6
0
 def ask(self, anActor, msg, timeout):
     txwatch = self._tx_to_actor(anActor, msg)  # KWQ: pass timeout on tx??
     askLimit = ExpiryTime(toTimeDeltaOrNone(timeout))
     while not askLimit.expired():
         response = self._run_transport(askLimit.remaining())
         if txwatch.failed:
             if txwatch.failure in [SendStatus.DeadTarget,
                                    SendStatus.Failed,
                                    SendStatus.NotSent]:
                 # Silent failure; not all transports can indicate
                 # this, so for conformity the Dead Letter handler is
                 # the intended method of handling this issue.
                 return None
             raise ActorSystemFailure('Transmit of ask message to %s failed (%s)'%(
                 str(anActor),
                 str(txwatch.failure)))
         if response is None:
             # Timed out, give up.
             return None
         # Do not send miscellaneous ActorSystemMessages to the
         # caller that it might not recognize.  If one of those was
         # recieved, loop to get another response.
         if response and \
            hasattr(response, 'message') and \
            not isInternalActorSystemMessage(response.message):
             return response.message
     return None
Example #7
0
 def unloadActorSource(self, sourceHash):
     loadLimit = ExpiryTime(MAX_LOAD_SOURCE_DELAY)
     txwatch = self._tx_to_admin(ValidateSource(sourceHash, None))
     while not loadLimit.expired():
         if not self._run_transport(loadLimit.remaining(), txonly=True):
             return  # all transmits completed
         if txwatch.failed:
             raise ActorSystemFailure(
                 'Error sending source unload to Admin: %s' %
                 str(txwatch.failure))
     raise ActorSystemRequestTimeout('Unload source timeout: ' +
                                     str(loadLimit))
Example #8
0
 def updateCapability(self, capabilityName, capabilityValue=None):
     attemptLimit = ExpiryTime(MAX_CAPABILITY_UPDATE_DELAY)
     txwatch = self._tx_to_admin(CapabilityUpdate(capabilityName,
                                                  capabilityValue))
     while not attemptLimit.expired():
         if not self._run_transport(attemptLimit.remaining(), txonly=True):
             return  # all transmits completed
         if txwatch.failed:
             raise ActorSystemFailure(
                 'Error sending capability updates to Admin: %s' %
                 str(txwatch.failure))
     raise ActorSystemRequestTimeout(
         'Unable to confirm capability update in %s' %
         str(MAX_CAPABILITY_UPDATE_DELAY))
Example #9
0
    def __init__(self, system, logDefs=None):
        self._numPrimaries = 0
        # Expects self.transport has already been set by subclass __init__
        self.adminAddr = self.transport.getAdminAddr(system.capabilities)
        tryingTime = ExpiryTime(MAX_SYSTEM_SHUTDOWN_DELAY +
                                timedelta(seconds=1))
        while not tryingTime.expired():
            if not self.transport.probeAdmin(self.adminAddr):
                self._startAdmin(self.adminAddr, self.transport.myAddress,
                                 system.capabilities, logDefs)
            if self._verifyAdminRunning(): return
            import time
            time.sleep(0.5)  # Previous version may have been exiting

        if not self._verifyAdminRunning():
            raise InvalidActorAddress(
                self.adminAddr, 'not a valid or useable ActorSystem Admin')
Example #10
0
    def __init__(self, system, logDefs = None):
        ensure_TZ_set()

        # Expects self.transport has already been set by subclass __init__
        super(systemBase, self).__init__(
            self.transport.getAdminAddr(system.capabilities))

        tryingTime = ExpiryTime(MAX_SYSTEM_SHUTDOWN_DELAY + timedelta(seconds=1))
        while not tryingTime.expired():
            if not self.transport.probeAdmin(self.adminAddr):
                self._startAdmin(self.adminAddr,
                                 self.transport.myAddress,
                                 system.capabilities,
                                 logDefs)
            if self._verifyAdminRunning(): return
            import time
            time.sleep(0.5)  # Previous version may have been exiting

        if not self._verifyAdminRunning():
            raise InvalidActorAddress(self.adminAddr,
                                          'not a valid or useable ActorSystem Admin')
Example #11
0
 def tell(self, anActor, msg):
     attemptLimit = ExpiryTime(MAX_TELL_PERIOD)
     import socket
     for attempt in range(5000):
         try:
             self.transport.scheduleTransmit(
                 None, TransmitIntent(anActor,
                                      msg,
                                      onError=self._tellFailed))
             while not attemptLimit.expired():
                 if not self.transport.run(TransmitOnly,
                                           attemptLimit.remaining()):
                     break  # all transmits completed
             return
         except socket.error as ex:
             import errno
             if errno.EMFILE == ex.errno:
                 import time
                 time.sleep(0.1)
             else:
                 raise
Example #12
0
 def shutdown(self):
     thesplog('ActorSystem shutdown requested.', level=logging.INFO)
     time_to_quit = ExpiryTime(MAX_SYSTEM_SHUTDOWN_DELAY)
     txwatch = self._tx_to_admin(SystemShutdown())
     while not time_to_quit.expired():
         response = self._run_transport(time_to_quit.remaining())
         if txwatch.failed:
             thesplog('Could not send shutdown request to Admin'
                      '; aborting but not necessarily stopped',
                      level=logging.WARNING)
             return
         if response:
             if isinstance(response.message, SystemShutdownCompleted):
                 break
             else:
                 thesplog('Expected shutdown completed message, got: %s', response.message,
                          level=logging.WARNING)
         else:
             thesplog('No response to Admin shutdown request; Actor system not completely shutdown',
                      level=logging.ERROR)
     self.transport.close()
     thesplog('ActorSystem shutdown complete.')
Example #13
0
 def loadActorSource(self, fname):
     loadLimit = ExpiryTime(MAX_LOAD_SOURCE_DELAY)
     f = fname if hasattr(fname, 'read') else open(fname, 'rb')
     try:
         d = f.read()
         import hashlib
         hval = hashlib.md5(d).hexdigest()
         txwatch = self._tx_to_admin(
             ValidateSource(hval, d, getattr(f, 'name',
                                             str(fname)
                                             if hasattr(fname, 'read')
                                             else fname)))
         while not loadLimit.expired():
             if not self._run_transport(loadLimit.remaining(), txonly=True):
                 # All transmits completed
                 return hval
             if txwatch.failed:
                 raise ActorSystemFailure(
                     'Error sending source load to Admin: %s' %
                     str(txwatch.failure))
         raise ActorSystemRequestTimeout('Load source timeout: ' +
                                         str(loadLimit))
     finally:
         f.close()
Example #14
0
class wakeupTransportBase(object):

    """The wakeupTransportBase is designed to be used as a mixin-base for
       a Transport class and provides handling for the wakeupAfter()
       functionality.

       This base mixin provides the primary .run() entrypoint for the
       transport and a .run_time ExpiryTime member that provides the
       remaining time-to-run period.

       The system can handle .wakeupAfter() requests by calling this
       class's .addWakeup() method with the datetime.timedelta for the
       wakeup to be scheduled.

       The Transport should provide the following:

         ._runWithExpiry(incomingHandler)

              Called by this class's .run() entrypoint to do the
              actual transport-specific run routine.  Should perform
              that activity while the self.run_time ExpiryTime is not
              expired (self.run_time will be updated when new
              wakeupAfter() events are scheduled).
    """

    def __init__(self, *args, **kw):
        super(wakeupTransportBase, self).__init__(*args, **kw)
        # _pendingWakeups: key = datetime for wakeup, value = list of
        # pending wakeupAfter msgs to restart at that time
        self._pendingWakeups = {}
        self._activeWakeups = []  # expired wakeups to be delivered


    def _updateStatusResponse(self, resp):
        "Called to update a Thespian_SystemStatus or Thespian_ActorStatus with common information"
        resp.addWakeups(self._pendingWakeups)
        for each in self._activeWakeups:
            resp.addPendingMessage(self.myAddress, self.myAddress, str(each.message))


    def run(self, incomingHandler, maximumDuration=None):
        """Core scheduling method; called by the current Actor process when
           idle to await new messages (or to do background
           processing).
        """
        self._max_runtime = ExpiryTime(maximumDuration)

        # Always make at least one pass through to handle expired wakeups
        # and queued events; otherwise a null/negative maximumDuration could
        # block all processing.
        firstTime = True

        while firstTime or not self._max_runtime.expired():
            firstTime = False
            now = datetime.now()
            self.run_time = min([ExpiryTime(P - now) for P in self._pendingWakeups] +
                                [self._max_runtime])
            rval = self._runWithExpiry(incomingHandler)
            if rval is not None:
                return rval

            if not self._realizeWakeups():
                # No wakeups were processed, and the inner run
                # returned, so assume there's nothing to do and exit
                return rval

            while self._activeWakeups:
                w = self._activeWakeups.pop()
                if incomingHandler in (None, TransmitOnly):
                    return w
                if not incomingHandler(w):
                    return None

        return None


    def addWakeup(self, timePeriod):
        now = datetime.now()
        wakeupTime = now + timePeriod
        self._pendingWakeups.setdefault(wakeupTime, []) \
                            .append(ReceiveEnvelope(self.myAddress, WakeupMessage(timePeriod)))
        self.run_time = min([ExpiryTime(P - now) for P in self._pendingWakeups] +
                            [self._max_runtime])


    def _realizeWakeups(self):
        "Find any expired wakeups and queue them to the send processing queue"
        now = datetime.now()
        removals = []
        for wakeupTime in self._pendingWakeups:
            if wakeupTime > now:
                continue
            self._activeWakeups.extend(self._pendingWakeups[wakeupTime])
            removals.append(wakeupTime)
        for each in removals:
            del self._pendingWakeups[each]
        return bool(removals)
Example #15
0
class LocalConventionState(object):
    def __init__(self, myAddress, capabilities, sCBStats,
                 getConventionAddressFunc):
        self._myAddress = myAddress
        self._capabilities = capabilities
        self._sCBStats = sCBStats
        self._conventionMembers = AssocList() # key=Remote Admin Addr, value=ConventionMemberData
        self._conventionNotificationHandlers = []
        self._getConventionAddr = getConventionAddressFunc
        self._conventionAddress = getConventionAddressFunc(capabilities)
        self._conventionRegistration = ExpiryTime(CONVENTION_REREGISTRATION_PERIOD)
        self._has_been_activated = False
        self._invited = False  # entered convention as a result of an explicit invite


    @property
    def myAddress(self):
        return self._myAddress

    @property
    def capabilities(self):
        return self._capabilities

    def updateStatusResponse(self, resp):
        resp.setConventionLeaderAddress(self.conventionLeaderAddr)
        resp.setConventionRegisterTime(self._conventionRegistration)
        for each in self._conventionMembers.values():
            resp.addConventioneer(each.remoteAddress, each.registryValid)
        resp.setNotifyHandlers(self._conventionNotificationHandlers)

    def active_in_convention(self):
        # If this is the convention leader, it is automatically
        # active, otherwise this convention member should have a
        # convention leader and that leader should have an active
        # entry in the _conventionMembers table (indicating it has
        # updated this system with its information)
        return bool(self.conventionLeaderAddr and
                    self._conventionMembers.find(self.conventionLeaderAddr))

    @property
    def conventionLeaderAddr(self):
        return self._conventionAddress

    def isConventionLeader(self):
        # Might also be the leader if self.conventionLeaderAddr is None
        return self.conventionLeaderAddr == self.myAddress

    def capabilities_have_changed(self, new_capabilities):
        self._capabilities = new_capabilities
        return self.setup_convention()

    def setup_convention(self, activation=False):
        self._has_been_activated |= activation
        rmsgs = []
        # If not specified in capabilities, don't override any invites
        # that may have been received.
        self._conventionAddress = self._getConventionAddr(self.capabilities) or \
                                  self._conventionAddress
        leader_is_gone = (self._conventionMembers.find(self.conventionLeaderAddr) is None) \
                         if self.conventionLeaderAddr else True
        if not self.isConventionLeader() and self.conventionLeaderAddr:
            thesplog('Admin registering with Convention @ %s (%s)',
                     self.conventionLeaderAddr,
                     'first time' if leader_is_gone else 're-registering',
                     level=logging.INFO, primary=True)
            rmsgs.append(
                HysteresisSend(self.conventionLeaderAddr,
                               ConventionRegister(self.myAddress,
                                                  self.capabilities,
                                                  leader_is_gone),
                               onSuccess = self._setupConventionCBGood,
                               onError = self._setupConventionCBError))
            rmsgs.append(LogAggregator(self.conventionLeaderAddr))
        self._conventionRegistration = ExpiryTime(CONVENTION_REREGISTRATION_PERIOD)
        return rmsgs

    def _setupConventionCBGood(self, result, finishedIntent):
        self._sCBStats.inc('Admin Convention Registered')
        if hasattr(self, '_conventionLeaderMissCount'):
            delattr(self, '_conventionLeaderMissCount')

    def _setupConventionCBError(self, result, finishedIntent):
        self._sCBStats.inc('Admin Convention Registration Failed')
        if hasattr(self, '_conventionLeaderMissCount'):
            self._conventionLeaderMissCount += 1
        else:
            self._conventionLeaderMissCount = 1
        thesplog('Admin cannot register with convention @ %s (miss %d): %s',
                 finishedIntent.targetAddr,
                 self._conventionLeaderMissCount,
                 result, level=logging.WARNING, primary=True)

    def got_convention_invite(self, sender):
        self._conventionAddress = sender
        self._invited = True
        return self.setup_convention()

    def got_convention_register(self, regmsg):
        # Called when remote convention member has sent a ConventionRegister message
        self._sCBStats.inc('Admin Handle Convention Registration')
        if self._invited and not self.conventionLeaderAddr:
            # Lost connection to an invitation-only convention.
            # Cannot join again until another invitation is received.
            return []
        # Registrant may re-register if changing capabilities
        rmsgs = []
        registrant = regmsg.adminAddress
        prereg = getattr(regmsg, 'preRegister', False)  # getattr used; see definition
        existing = self._conventionMembers.find(registrant)
        thesplog('Got Convention %sregistration from %s (%s) (new? %s)',
                 'pre-' if prereg else '',
                 registrant,
                 'first time' if regmsg.firstTime else 're-registering',
                 not existing,
                 level=logging.INFO)
        if registrant == self.myAddress:
            # Either remote failed getting an external address and is
            # using 127.0.0.1 or else this is a malicious attempt to
            # make us talk to ourselves.  Ignore it.
            thesplog('Convention registration from %s is an invalid address; ignoring.',
                     registrant,
                     level=logging.WARNING)
            return rmsgs

        existingPreReg = (
            # existing.preRegOnly
            # or existing.preRegistered
            existing.permanentEntry
        ) if existing else False
        notify = (not existing or existing.preRegOnly) and not prereg

        if regmsg.firstTime or not existing:
            if existing:
                existing = None
                notify = not prereg
                rmsgs.extend(self._remote_system_cleanup(registrant))
            newmember = ConventionMemberData(registrant,
                                             regmsg.capabilities,
                                             prereg)
            if prereg or existingPreReg:
                newmember.preRegistered = PreRegistration()
            self._conventionMembers.add(registrant, newmember)
        else:
            existing.refresh(regmsg.capabilities, prereg or existingPreReg)
            if not prereg:
                existing.preRegOnly = False

        if not self.isConventionLeader():
            self._conventionRegistration = ExpiryTime(CONVENTION_REREGISTRATION_PERIOD)

        # Convention Members normally periodically initiate a
        # membership message, to which the leader confirms by
        # responding; if this was a pre-registration, that identifies
        # this system as the "leader" for that remote.  Also, if the
        # remote sent this because it was a pre-registration leader,
        # it doesn't yet have all the member information so the member
        # should respond.
        #if self.isConventionLeader() or prereg or regmsg.firstTime:
        if prereg:
            rmsgs.append(HysteresisCancel(registrant))
            rmsgs.append(TransmitIntent(registrant, ConventionInvite()))
        elif (self.isConventionLeader() or prereg or regmsg.firstTime or \
           (existing and existing.permanentEntry)):
            # If we are the Convention Leader, this would be the point to
            # inform all other registrants of the new registrant.  At
            # present, there is no reciprocity here, so just update the
            # new registrant with the leader's info.
            rmsgs.append(
                TransmitIntent(registrant,
                               ConventionRegister(self.myAddress,
                                                  self.capabilities)))

        if notify:
            rmsgs.extend(self._notifications_of(
                ActorSystemConventionUpdate(registrant,
                                            regmsg.capabilities,
                                            True)))
        return rmsgs

    def _notifications_of(self, msg):
        return [TransmitIntent(H, msg) for H in self._conventionNotificationHandlers]

    def add_notification_handler(self, addr):
        if addr not in self._conventionNotificationHandlers:
            self._conventionNotificationHandlers.append(addr)
            # Now update the registrant on the current state of all convention members
            return [TransmitIntent(addr,
                                   ActorSystemConventionUpdate(M.remoteAddress,
                                                               M.remoteCapabilities,
                                                               True))
                    for M in self._conventionMembers.values()
                    if not M.preRegOnly]
        return []

    def remove_notification_handler(self, addr):
        self._conventionNotificationHandlers = [
            H for H in self._conventionNotificationHandlers
            if H != addr]

    def got_convention_deregister(self, deregmsg):
        self._sCBStats.inc('Admin Handle Convention De-registration')
        remoteAdmin = deregmsg.adminAddress
        if remoteAdmin == self.myAddress:
            # Either remote failed getting an external address and is
            # using 127.0.0.1 or else this is a malicious attempt to
            # make us talk to ourselves.  Ignore it.
            thesplog('Convention deregistration from %s is an invalid address; ignoring.',
                     remoteAdmin,
                     level=logging.WARNING)
        rmsgs = []
        if getattr(deregmsg, 'preRegistered', False): # see definition for getattr use
            existing = self._conventionMembers.find(remoteAdmin)
            if existing:
                existing.preRegistered = None
                rmsgs.append(TransmitIntent(remoteAdmin, ConventionDeRegister(self.myAddress)))
        return rmsgs + self._remote_system_cleanup(remoteAdmin)

    def got_system_shutdown(self):
        return self.exit_convention()

    def exit_convention(self):
        self.invited = False
        gen_ops = lambda addr: [HysteresisCancel(addr),
                                TransmitIntent(addr,
                                               ConventionDeRegister(self.myAddress)),
        ]
        terminate = lambda a: [ self._remote_system_cleanup(a), gen_ops(a) ][-1]
        if self.conventionLeaderAddr and \
           self.conventionLeaderAddr != self.myAddress:
            thesplog('Admin de-registering with Convention @ %s',
                     str(self.conventionLeaderAddr),
                     level=logging.INFO, primary=True)
            # Cache convention leader address because it might get reset by terminate()
            claddr = self.conventionLeaderAddr
            terminate(self.conventionLeaderAddr)
            return gen_ops(claddr)
        return join(fmap(terminate,
                         [M.remoteAddress
                          for M in self._conventionMembers.values()
                          if M.remoteAddress != self.myAddress]))

    def check_convention(self):
        rmsgs = []
        if not self._has_been_activated:
            return rmsgs
        if self.isConventionLeader() or not self.conventionLeaderAddr:
            missing = [ each
                        for each in self._conventionMembers.values()
                        if each.registryValid.expired() ]
            for each in missing:
                thesplog('%s missed %d checkins (%s); assuming it has died',
                         str(each),
                         CONVENTION_REGISTRATION_MISS_MAX,
                         str(each.registryValid),
                         level=logging.WARNING, primary=True)
                rmsgs.extend(self._remote_system_cleanup(each.remoteAddress))
            self._conventionRegistration = ExpiryTime(CONVENTION_REREGISTRATION_PERIOD)
        else:
            # Re-register with the Convention if it's time
            if self.conventionLeaderAddr and self._conventionRegistration.expired():
                if getattr(self, '_conventionLeaderMissCount', 0) >= \
                   CONVENTION_REGISTRATION_MISS_MAX:
                    thesplog('Admin convention registration lost @ %s (miss %d)',
                             self.conventionLeaderAddr,
                             self._conventionLeaderMissCount,
                             level=logging.WARNING, primary=True)
                    rmsgs.extend(self._remote_system_cleanup(self.conventionLeaderAddr))
                    self._conventionLeaderMissCount = 0
                else:
                    rmsgs.extend(self.setup_convention())

        for member in self._conventionMembers.values():
            if member.preRegistered and \
               member.preRegistered.pingValid.expired() and \
               not member.preRegistered.pingPending:
                member.preRegistered.pingPending = True
                # If remote misses a checkin, re-extend the
                # invitation.  This also helps re-initiate a socket
                # connection if a TxOnly socket has been lost.
                member.preRegistered.pingValid = ExpiryTime(
                    convention_reinvite_adjustment(CONVENTION_RESTART_PERIOD
                                                   if member.registryValid.expired()
                                                   else CONVENTION_REREGISTRATION_PERIOD))
                rmsgs.append(HysteresisSend(
                    member.remoteAddress, ConventionInvite(),
                    onSuccess = self._preRegQueryNotPending,
                    onError = self._preRegQueryNotPending))
        return rmsgs


    def _preRegQueryNotPending(self, result, finishedIntent):
        remoteAddr = finishedIntent.targetAddr
        member = self._conventionMembers.find(remoteAddr)
        if member and member.preRegistered:
            member.preRegistered.pingPending = False

    def _remote_system_cleanup(self, registrant):
        """Called when a RemoteActorSystem has exited and all associated
           Actors should be marked as exited and the ActorSystem
           removed from Convention membership.  This is also called on
           a First Time connection from the remote to discard any
           previous connection information.

        """
        thesplog('Convention cleanup or deregistration for %s (known? %s)',
                 registrant,
                 bool(self._conventionMembers.find(registrant)),
                 level=logging.INFO)
        rmsgs = [LostRemote(registrant)]
        cmr = self._conventionMembers.find(registrant)
        if not cmr or cmr.preRegOnly:
            return []

        # Send exited notification to conventionNotificationHandler (if any)
        for each in self._conventionNotificationHandlers:
            rmsgs.append(
                TransmitIntent(each,
                               ActorSystemConventionUpdate(cmr.remoteAddress,
                                                           cmr.remoteCapabilities,
                                                           False)))  # errors ignored

        # If the remote ActorSystem shutdown gracefully (i.e. sent
        # a Convention Deregistration) then it should not be
        # necessary to shutdown remote Actors (or notify of their
        # shutdown) because the remote ActorSystem should already
        # have caused this to occur.  However, it won't hurt, and
        # it's necessary if the remote ActorSystem did not exit
        # gracefully.

        for lpa, raa in cmr.hasRemoteActors:
            # ignore errors:
            rmsgs.append(TransmitIntent(lpa, ChildActorExited(raa)))
            # n.b. at present, this means that the parent might
            # get duplicate notifications of ChildActorExited; it
            # is expected that Actors can handle this.

        # Remove remote system from conventionMembers
        if not cmr.preRegistered:
            if registrant == self.conventionLeaderAddr and self._invited:
                self._conventionAddress = None
                # Don't clear invited: once invited, that
                # perpetually indicates this should be only a
                # member and never a leader.
            self._conventionMembers.rmv(registrant)
        else:
            # This conventionMember needs to stay because the
            # current system needs to continue issuing
            # registration pings.  By setting the registryValid
            # expiration to forever, this member won't re-time-out
            # and will therefore be otherwise ignored... until it
            # registers again at which point the membership will
            # be updated with new settings.
            cmr.registryValid = ExpiryTime(None)
            cmr.preRegOnly = True

        return rmsgs + [HysteresisCancel(registrant)]

    def sentByRemoteAdmin(self, envelope):
        for each in self._conventionMembers.values():
            if envelope.sender == each.remoteAddress:
                return True
        return False

    def convention_inattention_delay(self):
        return self._conventionRegistration or \
            ExpiryTime(CONVENTION_REREGISTRATION_PERIOD
                       if self.active_in_convention() or
                       self.isConventionLeader() else
                       CONVENTION_RESTART_PERIOD)

    def forward_pending_to_remote_system(self, childClass, envelope, sourceHash, acceptsCaps):
        alreadyTried = getattr(envelope.message, 'alreadyTried', [])

        remoteCandidates = [
            K
            for K in self._conventionMembers.values()
            if not K.registryValid.expired()
            and K.remoteAddress != envelope.sender # source Admin
            and K.remoteAddress not in alreadyTried
            and acceptsCaps(K.remoteCapabilities)]

        if not remoteCandidates:
            if self.isConventionLeader() or not self.conventionLeaderAddr:
                raise NoCompatibleSystemForActor(
                    childClass,
                    'No known ActorSystems can handle a %s for %s',
                    childClass, envelope.message.forActor)
            # Let the Convention Leader try to find an appropriate ActorSystem
            bestC = self.conventionLeaderAddr
        else:
            # distribute equally amongst candidates
            C = [(K.remoteAddress, len(K.hasRemoteActors))
                 for K in remoteCandidates]
            bestC = foldl(lambda best,possible:
                          best if best[1] <= possible[1] else possible,
                          C)[0]
            thesplog('Requesting creation of %s%s on remote admin %s',
                     envelope.message.actorClassName,
                     ' (%s)'%sourceHash if sourceHash else '',
                     bestC)
        if bestC not in alreadyTried:
            # Don't send request to this remote again, it has already
            # been tried.  This would also be indicated by that system
            # performing the add of self.myAddress as below, but if
            # there is disagreement between the local and remote
            # addresses, this addition will prevent continual
            # bounceback.
            alreadyTried.append(bestC)
        if self.myAddress not in alreadyTried:
            # Don't send request back to this actor system: it cannot
            # handle it
            alreadyTried.append(self.myAddress)
        envelope.message.alreadyTried = alreadyTried
        return [TransmitIntent(bestC, envelope.message)]


    def send_to_all_members(self, message, exception_list=None):
        return [HysteresisSend(M.remoteAddress, message)
                for M in self._conventionMembers.values()
                if M.remoteAddress not in (exception_list or [])]
Example #16
0
 def testZeroExpired(self):
     et = ExpiryTime(timedelta(seconds=0))
     assert et.expired()
Example #17
0
 def testNonZeroExpired(self):
     et = ExpiryTime(timedelta(milliseconds=10))
     assert not et.expired()
     sleep(et.remainingSeconds())
     assert et.expired()
Example #18
0
class LocalConventionState(object):
    def __init__(self, myAddress, capabilities, sCBStats,
                 getConventionAddressFunc):
        self._myAddress = myAddress
        self._capabilities = capabilities
        self._sCBStats = sCBStats
        self._conventionMembers = AssocList(
        )  # key=Remote Admin Addr, value=ConventionMemberData
        self._conventionNotificationHandlers = []
        self._getConventionAddr = getConventionAddressFunc
        self._conventionAddress = getConventionAddressFunc(capabilities)
        self._conventionRegistration = ExpiryTime(
            CONVENTION_REREGISTRATION_PERIOD)
        self._has_been_activated = False
        self._invited = False  # entered convention as a result of an explicit invite

    @property
    def myAddress(self):
        return self._myAddress

    @property
    def capabilities(self):
        return self._capabilities

    def updateStatusResponse(self, resp):
        resp.setConventionLeaderAddress(self.conventionLeaderAddr)
        resp.setConventionRegisterTime(self._conventionRegistration)
        for each in self._conventionMembers.values():
            resp.addConventioneer(each.remoteAddress, each.registryValid)
        resp.setNotifyHandlers(self._conventionNotificationHandlers)

    def active_in_convention(self):
        # If this is the convention leader, it is automatically
        # active, otherwise this convention member should have a
        # convention leader and that leader should have an active
        # entry in the _conventionMembers table (indicating it has
        # updated this system with its information)
        return bool(
            self.conventionLeaderAddr
            and self._conventionMembers.find(self.conventionLeaderAddr))

    @property
    def conventionLeaderAddr(self):
        return self._conventionAddress

    def isConventionLeader(self):
        # Might also be the leader if self.conventionLeaderAddr is None
        return self.conventionLeaderAddr == self.myAddress

    def capabilities_have_changed(self, new_capabilities):
        self._capabilities = new_capabilities
        return self.setup_convention()

    def setup_convention(self, activation=False):
        self._has_been_activated |= activation
        rmsgs = []
        # If not specified in capabilities, don't override any invites
        # that may have been received.
        self._conventionAddress = self._getConventionAddr(self.capabilities) or \
                                  self._conventionAddress
        leader_is_gone = (self._conventionMembers.find(self.conventionLeaderAddr) is None) \
                         if self.conventionLeaderAddr else True
        if not self.isConventionLeader() and self.conventionLeaderAddr:
            thesplog('Admin registering with Convention @ %s (%s)',
                     self.conventionLeaderAddr,
                     'first time' if leader_is_gone else 're-registering',
                     level=logging.INFO,
                     primary=True)
            rmsgs.append(
                HysteresisSend(self.conventionLeaderAddr,
                               ConventionRegister(self.myAddress,
                                                  self.capabilities,
                                                  leader_is_gone),
                               onSuccess=self._setupConventionCBGood,
                               onError=self._setupConventionCBError))
            rmsgs.append(LogAggregator(self.conventionLeaderAddr))
        self._conventionRegistration = ExpiryTime(
            CONVENTION_REREGISTRATION_PERIOD)
        return rmsgs

    def _setupConventionCBGood(self, result, finishedIntent):
        self._sCBStats.inc('Admin Convention Registered')
        if hasattr(self, '_conventionLeaderMissCount'):
            delattr(self, '_conventionLeaderMissCount')

    def _setupConventionCBError(self, result, finishedIntent):
        self._sCBStats.inc('Admin Convention Registration Failed')
        if hasattr(self, '_conventionLeaderMissCount'):
            self._conventionLeaderMissCount += 1
        else:
            self._conventionLeaderMissCount = 1
        thesplog('Admin cannot register with convention @ %s (miss %d): %s',
                 finishedIntent.targetAddr,
                 self._conventionLeaderMissCount,
                 result,
                 level=logging.WARNING,
                 primary=True)

    def got_convention_invite(self, sender):
        self._conventionAddress = sender
        self._invited = True
        return self.setup_convention()

    def got_convention_register(self, regmsg):
        # Called when remote convention member has sent a ConventionRegister message
        self._sCBStats.inc('Admin Handle Convention Registration')
        if self._invited and not self.conventionLeaderAddr:
            # Lost connection to an invitation-only convention.
            # Cannot join again until another invitation is received.
            return []
        # Registrant may re-register if changing capabilities
        rmsgs = []
        registrant = regmsg.adminAddress
        prereg = getattr(regmsg, 'preRegister',
                         False)  # getattr used; see definition
        existing = self._conventionMembers.find(registrant)
        thesplog('Got Convention %sregistration from %s (%s) (new? %s)',
                 'pre-' if prereg else '',
                 registrant,
                 'first time' if regmsg.firstTime else 're-registering',
                 not existing,
                 level=logging.INFO)
        if registrant == self.myAddress:
            # Either remote failed getting an external address and is
            # using 127.0.0.1 or else this is a malicious attempt to
            # make us talk to ourselves.  Ignore it.
            thesplog(
                'Convention registration from %s is an invalid address; ignoring.',
                registrant,
                level=logging.WARNING)
            return rmsgs

        existingPreReg = (
            # existing.preRegOnly
            # or existing.preRegistered
            existing.permanentEntry) if existing else False
        notify = (not existing or existing.preRegOnly) and not prereg

        if regmsg.firstTime or not existing:
            if existing:
                existing = None
                notify = not prereg
                rmsgs.extend(self._remote_system_cleanup(registrant))
            newmember = ConventionMemberData(registrant, regmsg.capabilities,
                                             prereg)
            if prereg or existingPreReg:
                newmember.preRegistered = PreRegistration()
            self._conventionMembers.add(registrant, newmember)
        else:
            existing.refresh(regmsg.capabilities, prereg or existingPreReg)
            if not prereg:
                existing.preRegOnly = False

        if not self.isConventionLeader():
            self._conventionRegistration = ExpiryTime(
                CONVENTION_REREGISTRATION_PERIOD)

        # Convention Members normally periodically initiate a
        # membership message, to which the leader confirms by
        # responding; if this was a pre-registration, that identifies
        # this system as the "leader" for that remote.  Also, if the
        # remote sent this because it was a pre-registration leader,
        # it doesn't yet have all the member information so the member
        # should respond.
        #if self.isConventionLeader() or prereg or regmsg.firstTime:
        if prereg:
            rmsgs.append(TransmitIntent(registrant, ConventionInvite()))
        elif (self.isConventionLeader() or prereg or regmsg.firstTime or \
           (existing and existing.permanentEntry)):
            # If we are the Convention Leader, this would be the point to
            # inform all other registrants of the new registrant.  At
            # present, there is no reciprocity here, so just update the
            # new registrant with the leader's info.
            rmsgs.append(
                TransmitIntent(
                    registrant,
                    ConventionRegister(self.myAddress, self.capabilities)))

        if notify:
            rmsgs.extend(
                self._notifications_of(
                    ActorSystemConventionUpdate(registrant,
                                                regmsg.capabilities, True)))
        return rmsgs

    def _notifications_of(self, msg):
        return [
            TransmitIntent(H, msg)
            for H in self._conventionNotificationHandlers
        ]

    def add_notification_handler(self, addr):
        if addr not in self._conventionNotificationHandlers:
            self._conventionNotificationHandlers.append(addr)
            # Now update the registrant on the current state of all convention members
            return [
                TransmitIntent(
                    addr,
                    ActorSystemConventionUpdate(M.remoteAddress,
                                                M.remoteCapabilities, True))
                for M in self._conventionMembers.values()
            ]
        return []

    def remove_notification_handler(self, addr):
        self._conventionNotificationHandlers = [
            H for H in self._conventionNotificationHandlers if H != addr
        ]

    def got_convention_deregister(self, deregmsg):
        self._sCBStats.inc('Admin Handle Convention De-registration')
        remoteAdmin = deregmsg.adminAddress
        if remoteAdmin == self.myAddress:
            # Either remote failed getting an external address and is
            # using 127.0.0.1 or else this is a malicious attempt to
            # make us talk to ourselves.  Ignore it.
            thesplog(
                'Convention deregistration from %s is an invalid address; ignoring.',
                remoteAdmin,
                level=logging.WARNING)
        rmsgs = []
        if getattr(deregmsg, 'preRegistered',
                   False):  # see definition for getattr use
            existing = self._conventionMembers.find(remoteAdmin)
            if existing:
                existing.preRegistered = None
                rmsgs.append(
                    TransmitIntent(remoteAdmin,
                                   ConventionDeRegister(self.myAddress)))
        return rmsgs + self._remote_system_cleanup(remoteAdmin)

    def got_system_shutdown(self):
        return self.exit_convention()

    def exit_convention(self):
        self.invited = False
        gen_ops = lambda addr: [
            HysteresisCancel(addr),
            TransmitIntent(addr, ConventionDeRegister(self.myAddress)),
        ]
        terminate = lambda a: [self._remote_system_cleanup(a), gen_ops(a)][-1]
        if self.conventionLeaderAddr and \
           self.conventionLeaderAddr != self.myAddress:
            thesplog('Admin de-registering with Convention @ %s',
                     str(self.conventionLeaderAddr),
                     level=logging.INFO,
                     primary=True)
            # Cache convention leader address because it might get reset by terminate()
            claddr = self.conventionLeaderAddr
            terminate(self.conventionLeaderAddr)
            return gen_ops(claddr)
        return join(
            fmap(terminate, [
                M.remoteAddress for M in self._conventionMembers.values()
                if M.remoteAddress != self.myAddress
            ]))

    def check_convention(self):
        rmsgs = []
        if not self._has_been_activated:
            return rmsgs
        if self.isConventionLeader() or not self.conventionLeaderAddr:
            missing = [
                each for each in self._conventionMembers.values()
                if each.registryValid.expired()
            ]
            for each in missing:
                thesplog('%s missed %d checkins (%s); assuming it has died',
                         str(each),
                         CONVENTION_REGISTRATION_MISS_MAX,
                         str(each.registryValid),
                         level=logging.WARNING,
                         primary=True)
                rmsgs.extend(self._remote_system_cleanup(each.remoteAddress))
            self._conventionRegistration = ExpiryTime(
                CONVENTION_REREGISTRATION_PERIOD)
        else:
            # Re-register with the Convention if it's time
            if self.conventionLeaderAddr and self._conventionRegistration.expired(
            ):
                if getattr(self, '_conventionLeaderMissCount', 0) >= \
                   CONVENTION_REGISTRATION_MISS_MAX:
                    thesplog(
                        'Admin convention registration lost @ %s (miss %d)',
                        self.conventionLeaderAddr,
                        self._conventionLeaderMissCount,
                        level=logging.ERROR,
                        primary=True)
                    rmsgs.extend(
                        self._remote_system_cleanup(self.conventionLeaderAddr))
                    self._conventionLeaderMissCount = 0
                else:
                    rmsgs.extend(self.setup_convention())

        for member in self._conventionMembers.values():
            if member.preRegistered and \
               member.preRegistered.pingValid.expired() and \
               not member.preRegistered.pingPending:
                member.preRegistered.pingPending = True
                # If remote misses a checkin, re-extend the
                # invitation.  This also helps re-initiate a socket
                # connection if a TxOnly socket has been lost.
                member.preRegistered.pingValid = ExpiryTime(
                    convention_reinvite_adjustment(
                        CONVENTION_RESTART_PERIOD if member.registryValid.
                        expired() else CONVENTION_REREGISTRATION_PERIOD))
                rmsgs.append(
                    HysteresisSend(member.remoteAddress,
                                   ConventionInvite(),
                                   onSuccess=self._preRegQueryNotPending,
                                   onError=self._preRegQueryNotPending))
        return rmsgs

    def _preRegQueryNotPending(self, result, finishedIntent):
        remoteAddr = finishedIntent.targetAddr
        member = self._conventionMembers.find(remoteAddr)
        if member and member.preRegistered:
            member.preRegistered.pingPending = False

    def _remote_system_cleanup(self, registrant):
        """Called when a RemoteActorSystem has exited and all associated
           Actors should be marked as exited and the ActorSystem
           removed from Convention membership.  This is also called on
           a First Time connection from the remote to discard any
           previous connection information.

        """
        thesplog('Convention cleanup or deregistration for %s (known? %s)',
                 registrant,
                 bool(self._conventionMembers.find(registrant)),
                 level=logging.INFO)
        rmsgs = [LostRemote(registrant)]
        cmr = self._conventionMembers.find(registrant)
        if not cmr or cmr.preRegOnly:
            return []

        # Send exited notification to conventionNotificationHandler (if any)
        for each in self._conventionNotificationHandlers:
            rmsgs.append(
                TransmitIntent(
                    each,
                    ActorSystemConventionUpdate(cmr.remoteAddress,
                                                cmr.remoteCapabilities,
                                                False)))  # errors ignored

        # If the remote ActorSystem shutdown gracefully (i.e. sent
        # a Convention Deregistration) then it should not be
        # necessary to shutdown remote Actors (or notify of their
        # shutdown) because the remote ActorSystem should already
        # have caused this to occur.  However, it won't hurt, and
        # it's necessary if the remote ActorSystem did not exit
        # gracefully.

        for lpa, raa in cmr.hasRemoteActors:
            # ignore errors:
            rmsgs.append(TransmitIntent(lpa, ChildActorExited(raa)))
            # n.b. at present, this means that the parent might
            # get duplicate notifications of ChildActorExited; it
            # is expected that Actors can handle this.

        # Remove remote system from conventionMembers
        if not cmr.preRegistered:
            if registrant == self.conventionLeaderAddr and self._invited:
                self._conventionAddress = None
                # Don't clear invited: once invited, that
                # perpetually indicates this should be only a
                # member and never a leader.
            self._conventionMembers.rmv(registrant)
        else:
            # This conventionMember needs to stay because the
            # current system needs to continue issuing
            # registration pings.  By setting the registryValid
            # expiration to forever, this member won't re-time-out
            # and will therefore be otherwise ignored... until it
            # registers again at which point the membership will
            # be updated with new settings.
            cmr.registryValid = ExpiryTime(None)
            cmr.preRegOnly = True

        return rmsgs + [HysteresisCancel(registrant)]

    def sentByRemoteAdmin(self, envelope):
        for each in self._conventionMembers.values():
            if envelope.sender == each.remoteAddress:
                return True
        return False

    def convention_inattention_delay(self):
        return self._conventionRegistration or \
            ExpiryTime(CONVENTION_REREGISTRATION_PERIOD
                       if self.active_in_convention() or
                       self.isConventionLeader() else
                       CONVENTION_RESTART_PERIOD)

    def forward_pending_to_remote_system(self, childClass, envelope,
                                         sourceHash, acceptsCaps):
        alreadyTried = getattr(envelope.message, 'alreadyTried', [])

        remoteCandidates = [
            K for K in self._conventionMembers.values()
            if not K.registryValid.expired()
            and K.remoteAddress != envelope.sender  # source Admin
            and K.remoteAddress not in alreadyTried
            and acceptsCaps(K.remoteCapabilities)
        ]

        if not remoteCandidates:
            if self.isConventionLeader() or not self.conventionLeaderAddr:
                raise NoCompatibleSystemForActor(
                    childClass, 'No known ActorSystems can handle a %s for %s',
                    childClass, envelope.message.forActor)
            # Let the Convention Leader try to find an appropriate ActorSystem
            bestC = self.conventionLeaderAddr
        else:
            # distribute equally amongst candidates
            C = [(K.remoteAddress, len(K.hasRemoteActors))
                 for K in remoteCandidates]
            bestC = foldl(
                lambda best, possible: best
                if best[1] <= possible[1] else possible, C)[0]
            thesplog('Requesting creation of %s%s on remote admin %s',
                     envelope.message.actorClassName,
                     ' (%s)' % sourceHash if sourceHash else '', bestC)
        if bestC not in alreadyTried:
            # Don't send request to this remote again, it has already
            # been tried.  This would also be indicated by that system
            # performing the add of self.myAddress as below, but if
            # there is disagreement between the local and remote
            # addresses, this addition will prevent continual
            # bounceback.
            alreadyTried.append(bestC)
        if self.myAddress not in alreadyTried:
            # Don't send request back to this actor system: it cannot
            # handle it
            alreadyTried.append(self.myAddress)
        envelope.message.alreadyTried = alreadyTried
        return [TransmitIntent(bestC, envelope.message)]

    def send_to_all_members(self, message, exception_list=None):
        return [
            HysteresisSend(M.remoteAddress, message)
            for M in self._conventionMembers.values()
            if M.remoteAddress not in (exception_list or [])
        ]
Example #19
0
 def testNoneExpired(self):
     et = ExpiryTime(None)
     assert not et.expired()
Example #20
0
 def drainTransmits(self):
     drainLimit = ExpiryTime(MAX_SHUTDOWN_DRAIN_PERIOD)
     while not drainLimit.expired():
         if not self.transport.run(TransmitOnly, drainLimit.remaining()):
             break  # no transmits left
Example #21
0
 def testNonZeroExpired(self):
     et = ExpiryTime(timedelta(milliseconds=10))
     assert not et.expired()
     sleep(et.remainingSeconds())
     assert et.expired()
Example #22
0
 def testNoneExpired(self):
     et = ExpiryTime(None)
     assert not et.expired()
Example #23
0
class HysteresisDelaySender(object):
    """Implements hysteresis delay for sending messages.  This is intended
       to be used for messages exchanged between convention members to
       ensure that a mis-behaved member doesn't have the ability to
       inflict damage on the entire convention.  The first time a
       message is sent via this sender it is passed on through, but
       that starts a blackout period that starts with the
       CONVENTION_HYSTERESIS_MIN_PERIOD.  Each additional send attempt
       during that blackout period will cause the blackout period to
       be extended by the CONVENTION_HYSTERESIS_RATE, up to the
       CONVENTION_HYSTERESIS_MAX_PERIOD.  Once the blackout period
       ends, the queued sends will be sent, but only the last
       attempted message of each type for the specified remote target.
       At that point, the hysteresis delay will be reduced by the
       CONVENTION_HYSTERESIS_RATE; further send attempts will affect
       the hysteresis blackout period as described as above but lack
       of sending attempts will continue to reduce the hysteresis back
       to a zero-delay setting.

       Note: delays are updated in a target-independent manner; the
             target is only considered when eliminating duplicates.

       Note: maxDelay on TransmitIntents is ignored by hysteresis
             delays.  It is assumed that a transmit intent's maxDelay
             is greater than the maximum hysteresis period and/or that
             the hysteresis delay is more important than the transmit
             intent timeout.
    """
    def __init__(self,
                 actual_sender,
                 hysteresis_min_period=HYSTERESIS_MIN_PERIOD,
                 hysteresis_max_period=HYSTERESIS_MAX_PERIOD,
                 hysteresis_rate=HYSTERESIS_RATE):
        self._sender = actual_sender
        self._hysteresis_until = ExpiryTime(timedelta(seconds=0))
        self._hysteresis_queue = []
        self._current_hysteresis = None  # timedelta
        self._hysteresis_min_period = hysteresis_min_period
        self._hysteresis_max_period = hysteresis_max_period
        self._hysteresis_rate = hysteresis_rate

    @property
    def delay(self):
        return self._hysteresis_until

    def _has_hysteresis(self):
        return (self._current_hysteresis is not None
                and self._current_hysteresis >= self._hysteresis_min_period)

    def _increase_hysteresis(self):
        if self._has_hysteresis():
            try:
                self._current_hysteresis = min(
                    (self._current_hysteresis * self._hysteresis_rate),
                    self._hysteresis_max_period)
            except TypeError:
                # See note below for _decrease_hysteresis
                self._current_hysteresis = min(
                    timedelta(seconds=(self._current_hysteresis.seconds *
                                       self._hysteresis_rate)),
                    self._hysteresis_max_period)
        else:
            self._current_hysteresis = self._hysteresis_min_period

    def _decrease_hysteresis(self):
        try:
            self._current_hysteresis = ((self._current_hysteresis /
                                         self._hysteresis_rate)
                                        if self._has_hysteresis() else None)
        except TypeError:
            # Python 2.x cannot multiply or divide a timedelta by a
            # fractional amount.  There is also not a total_seconds
            # retrieval from a timedelta, but it should be safe to
            # assume that the hysteresis value is not greater than 1
            # day.
            self._current_hysteresis = timedelta(
                seconds=(self._current_hysteresis.seconds /
                         self._hysteresis_rate)) \
                if self._has_hysteresis() else None

    def _update_remaining_hysteresis_period(self, reset=False):
        if not self._current_hysteresis:
            self._hysteresis_until = ExpiryTime(timedelta(seconds=0))
        else:
            if reset or not self._hysteresis_until:
                self._hysteresis_until = ExpiryTime(self._current_hysteresis)
            else:
                self._hysteresis_until = ExpiryTime(
                    self._current_hysteresis -
                    self._hysteresis_until.remaining())

    def checkSends(self):
        if self.delay.expired():
            self._decrease_hysteresis()
            self._update_remaining_hysteresis_period(reset=True)
            for intent in self._keepIf(lambda M: False):
                self._sender(intent)

    @staticmethod
    def safe_cmp(val1, val2):
        try:
            return val1 == val2
        except Exception:
            return False

    def sendWithHysteresis(self, intent):
        if self._hysteresis_until.expired():
            self._current_hysteresis = self._hysteresis_min_period
            self._sender(intent)
        else:
            dups = self._keepIf(lambda M: (M.targetAddr != intent.targetAddr or
                                           not HysteresisDelaySender.safe_cmp(
                                               M.message, intent.message)))
            # The dups are duplicate sends to the new intent's target;
            # complete them when the actual message is finally sent
            # with the same result
            if dups:
                intent.addCallback(self._dupSentGood(dups),
                                   self._dupSentFail(dups))
            self._hysteresis_queue.append(intent)
            self._increase_hysteresis()
        self._update_remaining_hysteresis_period()

    def cancelSends(self, remoteAddr):
        for each in self._keepIf(lambda M: M.targetAddr != remoteAddr):
            each.tx_done(SendStatus.Failed)

    def _keepIf(self, keepFunc):
        requeues, removes = partition(keepFunc, self._hysteresis_queue)
        self._hysteresis_queue = requeues
        return removes

    @staticmethod
    def _dupSentGood(dups):
        def _finishDups(result, finishedIntent):
            for each in dups:
                each.tx_done(result)

        return _finishDups

    @staticmethod
    def _dupSentFail(dups):
        def _finishDups(result, finishedIntent):
            for each in dups:
                each.tx_done(result)

        return _finishDups
Example #24
0
 def testZeroExpired(self):
     et = ExpiryTime(timedelta(seconds=0))
     assert et.expired()