Viewing file:  batch.py (37.84 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
# -*- test-case-name: axiom.test.test_batch -*-
"""
Utilities for performing repetitive tasks over potentially large sets
of data over an extended period of time.
"""
import weakref, datetime, os, sys
from zope.interface import implements
from twisted.python import reflect, failure, log, procutils, util, runtime
from twisted.internet import task, defer, reactor, error, protocol
from twisted.application import service
from epsilon import extime, process, cooperator, modal, juice
from axiom import iaxiom, errors as eaxiom, item, attributes
from axiom.scheduler import Scheduler, SubScheduler
from axiom.upgrade import registerUpgrader, registerDeletionUpgrader
from axiom.dependency import installOn
VERBOSE = False
_processors = weakref.WeakValueDictionary()
class _NoWorkUnits(Exception):
"""
Raised by a _ReliableListener's step() method to indicate it
didn't do anything.
"""
class _ProcessingFailure(Exception):
"""
Raised when processItem raises any exception. This is never raised
directly, but instances of the three subclasses are.
"""
def __init__(self, reliableListener, workUnit, failure):
Exception.__init__(self)
self.reliableListener = reliableListener
self.workUnit = workUnit
self.failure = failure
# Get rid of all references this failure is holding so that it doesn't
# cause any crazy object leaks. See also the comment in
# BatchProcessingService.step's except suite.
self.failure.cleanFailure()
def mark(self):
"""
Mark the unit of work as failed in the database and update the listener
so as to skip it next time.
"""
self.reliableListener.lastRun = extime.Time()
BatchProcessingError(
store=self.reliableListener.store,
processor=self.reliableListener.processor,
listener=self.reliableListener.listener,
item=self.workUnit,
error=self.failure.getErrorMessage())
class _ForwardProcessingFailure(_ProcessingFailure):
"""
An error occurred in a reliable listener while processing items forward
from the mark.
"""
def mark(self):
_ProcessingFailure.mark(self)
self.reliableListener.forwardMark = self.workUnit.storeID
class _BackwardProcessingFailure(_ProcessingFailure):
"""
An error occurred in a reliable listener while processing items backwards
from the mark.
"""
def mark(self):
_ProcessingFailure.mark(self)
self.reliableListener.backwardMark = self.workUnit.storeID
class _TrackedProcessingFailure(_ProcessingFailure):
"""
An error occurred in a reliable listener while processing items specially
added to the batch run.
"""
class BatchProcessingError(item.Item):
processor = attributes.reference(doc="""
The batch processor which owns this failure.
""")
listener = attributes.reference(doc="""
The listener which caused this error.
""")
item = attributes.reference(doc="""
The item which actually failed to be processed.
""")
error = attributes.bytes(doc="""
The error message which was associated with this failure.
""")
class _ReliableTracker(item.Item):
"""
A tracking item for an out-of-sequence item which a reliable listener
should be given to process.
These are created when L{_ReliableListener.addItem} is called and the
specified item is in the range of items which have already been processed.
"""
processor = attributes.reference(doc="""
The batch processor which owns this tracker.
""")
listener = attributes.reference(doc="""
The listener which is responsible for this tracker's item.
""")
item = attributes.reference(doc="""
The item which this is tracking.
""")
class _ReliableListener(item.Item):
processor = attributes.reference(doc="""
The batch processor which owns this listener.
""")
listener = attributes.reference(doc="""
The item which is actually the listener.
""")
backwardMark = attributes.integer(doc="""
Store ID of the first Item after the next Item to be processed in
the backwards direction. Usually, the Store ID of the Item
previously processed in the backwards direction.
""")
forwardMark = attributes.integer(doc="""
Store ID of the first Item before the next Item to be processed in
the forwards direction. Usually, the Store ID of the Item
previously processed in the forwards direction.
""")
lastRun = attributes.timestamp(doc="""
Time indicating the last chance given to this listener to do some
work.
""")
style = attributes.integer(doc="""
Either L{iaxiom.LOCAL} or L{iaxiom.REMOTE}. Indicates where the
batch processing should occur, in the main process or a
subprocess.
""")
def __repr__(self):
return '<ReliableListener %s %r #%r>' % ({iaxiom.REMOTE: 'remote',
iaxiom.LOCAL: 'local'}[self.style],
self.listener,
self.storeID)
def addItem(self, item):
assert type(item) is self.processor.workUnitType, \
"Adding work unit of type %r to listener for type %r" % (
type(item), self.processor.workUnitType)
if item.storeID >= self.backwardMark and item.storeID <= self.forwardMark:
_ReliableTracker(store=self.store,
listener=self,
item=item)
def _forwardWork(self, workUnitType):
if VERBOSE:
log.msg("%r looking forward from %r" % (self, self.forwardMark,))
return self.store.query(
workUnitType,
workUnitType.storeID > self.forwardMark,
sort=workUnitType.storeID.ascending,
limit=2)
def _backwardWork(self, workUnitType):
if VERBOSE:
log.msg("%r looking backward from %r" % (self, self.backwardMark,))
if self.backwardMark == 0:
return []
return self.store.query(
workUnitType,
workUnitType.storeID < self.backwardMark,
sort=workUnitType.storeID.descending,
limit=2)
def _extraWork(self):
return self.store.query(_ReliableTracker,
_ReliableTracker.listener == self,
limit=2)
def _doOneWork(self, workUnit, failureType):
if VERBOSE:
log.msg("Processing a unit of work: %r" % (workUnit,))
try:
self.listener.processItem(workUnit)
except:
f = failure.Failure()
if VERBOSE:
log.msg("Processing failed: %s" % (f.getErrorMessage(),))
log.err(f)
raise failureType(self, workUnit, f)
def step(self):
first = True
for workTracker in self._extraWork():
if first:
first = False
else:
return True
item = workTracker.item
workTracker.deleteFromStore()
self._doOneWork(item, _TrackedProcessingFailure)
for workUnit in self._forwardWork(self.processor.workUnitType):
if first:
first = False
else:
return True
self.forwardMark = workUnit.storeID
self._doOneWork(workUnit, _ForwardProcessingFailure)
for workUnit in self._backwardWork(self.processor.workUnitType):
if first:
first = False
else:
return True
self.backwardMark = workUnit.storeID
self._doOneWork(workUnit, _BackwardProcessingFailure)
if first:
raise _NoWorkUnits()
if VERBOSE:
log.msg("%r.step() returning False" % (self,))
return False
class _BatchProcessorMixin:
def step(self, style=iaxiom.LOCAL, skip=()):
now = extime.Time()
first = True
for listener in self.store.query(_ReliableListener,
attributes.AND(_ReliableListener.processor == self,
_ReliableListener.style == style,
_ReliableListener.listener.notOneOf(skip)),
sort=_ReliableListener.lastRun.ascending):
if not first:
if VERBOSE:
log.msg("Found more work to do, returning True from %r.step()" % (self,))
return True
listener.lastRun = now
try:
if listener.step():
if VERBOSE:
log.msg("%r.step() reported more work to do, returning True from %r.step()" % (listener, self))
return True
except _NoWorkUnits:
if VERBOSE:
log.msg("%r.step() reported no work units" % (listener,))
else:
first = False
if VERBOSE:
log.msg("No listeners left with work, returning False from %r.step()" % (self,))
return False
def run(self):
"""
Try to run one unit of work through one listener. If there are more
listeners or more work, reschedule this item to be run again in
C{self.busyInterval} milliseconds, otherwise unschedule it.
@rtype: L{extime.Time} or C{None}
@return: The next time at which to run this item, used by the scheduler
for automatically rescheduling, or None if there is no more work to do.
"""
now = extime.Time()
if self.step():
self.scheduled = now + datetime.timedelta(milliseconds=self.busyInterval)
else:
self.scheduled = None
return self.scheduled
def timedEventErrorHandler(self, timedEvent, failureObj):
failureObj.trap(_ProcessingFailure)
log.msg("Batch processing failure")
log.err(failureObj.value.failure)
failureObj.value.mark()
return extime.Time() + datetime.timedelta(milliseconds=self.busyInterval)
def addReliableListener(self, listener, style=iaxiom.LOCAL):
"""
Add the given Item to the set which will be notified of Items
available for processing.
Note: Each Item is processed synchronously. Adding too many
listeners to a single batch processor will cause the L{step}
method to block while it sends notification to each listener.
@param listener: An Item instance which provides a
C{processItem} method.
@return: An Item representing L{listener}'s persistent tracking state.
"""
existing = self.store.findUnique(_ReliableListener,
attributes.AND(_ReliableListener.processor == self,
_ReliableListener.listener == listener),
default=None)
if existing is not None:
return existing
for work in self.store.query(self.workUnitType,
sort=self.workUnitType.storeID.descending,
limit=1):
forwardMark = work.storeID
backwardMark = work.storeID + 1
break
else:
forwardMark = 0
backwardMark = 0
if self.scheduled is None:
self.scheduled = extime.Time()
iaxiom.IScheduler(self.store).schedule(self, self.scheduled)
return _ReliableListener(store=self.store,
processor=self,
listener=listener,
forwardMark=forwardMark,
backwardMark=backwardMark,
style=style)
def removeReliableListener(self, listener):
"""
Remove a previously added listener.
"""
self.store.query(_ReliableListener,
attributes.AND(_ReliableListener.processor == self,
_ReliableListener.listener == listener)).deleteFromStore()
self.store.query(BatchProcessingError,
attributes.AND(BatchProcessingError.processor == self,
BatchProcessingError.listener == listener)).deleteFromStore()
def getReliableListeners(self):
"""
Return an iterable of the listeners which have been added to
this batch processor.
"""
for rellist in self.store.query(_ReliableListener, _ReliableListener.processor == self):
yield rellist.listener
def getFailedItems(self):
"""
Return an iterable of two-tuples of listeners which raised an
exception from C{processItem} and the item which was passed as
the argument to that method.
"""
for failed in self.store.query(BatchProcessingError, BatchProcessingError.processor == self):
yield (failed.listener, failed.item)
def itemAdded(self):
"""
Called to indicate that a new item of the type monitored by this batch
processor is being added to the database.
If this processor is not already scheduled to run, this will schedule
it.
"""
localCount = self.store.query(
_ReliableListener,
attributes.AND(_ReliableListener.processor == self,
_ReliableListener.style == iaxiom.LOCAL),
limit=1).count()
if localCount and self.scheduled is None:
self.scheduled = extime.Time()
iaxiom.IScheduler(self.store).schedule(self, self.scheduled)
def upgradeProcessor1to2(oldProcessor):
"""
Batch processors stopped polling at version 2, so they no longer needed the
idleInterval attribute. They also gained a scheduled attribute which
tracks their interaction with the scheduler. Since they stopped polling,
we also set them up as a timed event here to make sure that they don't
silently disappear, never to be seen again: running them with the scheduler
gives them a chance to figure out what's up and set up whatever other state
they need to continue to run.
Since this introduces a new dependency of all batch processors on a powerup
for the IScheduler, install a Scheduler or a SubScheduler if one is not
already present.
"""
newProcessor = oldProcessor.upgradeVersion(
oldProcessor.typeName, 1, 2,
busyInterval=oldProcessor.busyInterval)
newProcessor.scheduled = extime.Time()
s = newProcessor.store
sch = iaxiom.IScheduler(s, None)
if sch is None:
if s.parent is None:
# Only site stores have no parents.
sch = Scheduler(store=s)
else:
# Substores get subschedulers.
sch = SubScheduler(store=s)
installOn(sch, s)
# And set it up to run.
sch.schedule(newProcessor, newProcessor.scheduled)
return newProcessor
def processor(forType):
"""
Create an Axiom Item type which is suitable to use as a batch processor for
the given Axiom Item type.
Processors created this way depend on a L{iaxiom.IScheduler} powerup on the
on which store they are installed.
@type forType: L{item.MetaItem}
@param forType: The Axiom Item type for which to create a batch processor
type.
@rtype: L{item.MetaItem}
@return: An Axiom Item type suitable for use as a batch processor. If such
a type previously existed, it will be returned. Otherwise, a new type is
created.
"""
MILLI = 1000
if forType not in _processors:
def __init__(self, *a, **kw):
item.Item.__init__(self, *a, **kw)
self.store.powerUp(self, iaxiom.IBatchProcessor)
attrs = {
'__name__': 'Batch_' + forType.__name__,
'__module__': forType.__module__,
'__init__': __init__,
'__repr__': lambda self: '<Batch of %s #%d>' % (reflect.qual(self.workUnitType), self.storeID),
'schemaVersion': 2,
'workUnitType': forType,
'scheduled': attributes.timestamp(doc="""
The next time at which this processor is scheduled to run.
""", default=None),
# MAGIC NUMBERS AREN'T THEY WONDERFUL?
'busyInterval': attributes.integer(doc="", default=MILLI / 10),
}
_processors[forType] = item.MetaItem(
attrs['__name__'],
(item.Item, _BatchProcessorMixin),
attrs)
registerUpgrader(
upgradeProcessor1to2,
_processors[forType].typeName,
1, 2)
return _processors[forType]
class ProcessUnavailable(Exception):
"""Indicates the process is not available to perform tasks.
This is a transient error. Calling code should handle it by
arranging to do the work they planned on doing at a later time.
"""
class Shutdown(juice.Command):
"""
Abandon, belay, cancel, cease, close, conclude, cut it out, desist,
determine, discontinue, drop it, end, finish, finish up, give over, go
amiss, go astray, go wrong, halt, have done with, hold, knock it off, lay
off, leave off, miscarry, perorate, quit, refrain, relinquish, renounce,
resolve, scrap, scratch, scrub, stay, stop, terminate, wind up.
"""
commandName = "Shutdown"
responseType = juice.QuitBox
def _childProcTerminated(self, err):
self.mode = 'stopped'
err = ProcessUnavailable(err)
for d in self.waitingForProcess:
d.errback(err)
del self.waitingForProcess
class ProcessController(object):
"""
Stateful class which tracks a Juice connection to a child process.
Communication occurs over stdin and stdout of the child process. The
process is launched and restarted as necessary. Failures due to the child
process terminating, either unilaterally of by request, are represented as
a transient exception class,
Mode is one of::
- 'stopped' (no process running or starting)
- 'starting' (process begun but not ready for requests)
- 'ready' (process ready for requests)
- 'stopping' (process being torn down)
- 'waiting_ready' (process beginning but will be shut down
as soon as it starts up)
Transitions are as follows::
getProcess:
stopped -> starting:
launch process
create/save in waitingForStartup/return Deferred
starting -> starting:
create/save/return Deferred
ready -> ready:
return saved process
stopping:
return failing Deferred indicating transient failure
waiting_ready:
return failing Deferred indicating transient failure
stopProcess:
stopped -> stopped:
return succeeding Deferred
starting -> waiting_ready:
create Deferred, add transient failure errback handler, return
ready -> stopping:
call shutdown on process
return Deferred which fires when shutdown is done
childProcessCreated:
starting -> ready:
callback saved Deferreds
clear saved Deferreds
waiting_ready:
errback saved Deferred indicating transient failure
return _shutdownIndexerProcess()
childProcessTerminated:
starting -> stopped:
errback saved Deferreds indicating transient failure
waiting_ready -> stopped:
errback saved Deferreds indicating transient failure
ready -> stopped:
drop reference to process object
stopping -> stopped:
Callback saved shutdown deferred
@ivar process: A reference to the process object. Set in every non-stopped
mode.
@ivar juice: A reference to the juice protocol. Set in all modes.
@ivar connector: A reference to the process protocol. Set in every
non-stopped mode.
@ivar onProcessStartup: None or a no-argument callable which will
be invoked whenever the connection is first established to a newly
spawned child process.
@ivar onProcessTermination: None or a no-argument callable which
will be invoked whenever a Juice connection is lost, except in the
case where process shutdown was explicitly requested via
stopProcess().
"""
__metaclass__ = modal.ModalType
initialMode = 'stopped'
modeAttribute = 'mode'
# A reference to the Twisted process object which corresponds to
# the child process we have spawned. Set to a non-None value in
# every state except stopped.
process = None
# A reference to the process protocol object via which we
# communicate with the process's stdin and stdout. Set to a
# non-None value in every state except stopped.
connector = None
def __init__(self, name, juice, tacPath,
onProcessStartup=None,
onProcessTermination=None,
logPath=None,
pidPath=None):
self.name = name
self.juice = juice
self.tacPath = tacPath
self.onProcessStartup = onProcessStartup
self.onProcessTermination = onProcessTermination
if logPath is None:
logPath = name + '.log'
if pidPath is None:
pidPath = name + '.pid'
self.logPath = logPath
self.pidPath = pidPath
def _startProcess(self):
executable = sys.executable
env = os.environ
env['PYTHONPATH'] = os.pathsep.join(sys.path)
twistdBinaries = procutils.which("twistd2.4") + procutils.which("twistd")
if not twistdBinaries:
return defer.fail(RuntimeError("Couldn't find twistd to start subprocess"))
twistd = twistdBinaries[0]
setsid = procutils.which("setsid")
self.connector = JuiceConnector(self.juice, self)
args = [
sys.executable,
twistd,
'--logfile=%s' % (self.logPath,)]
if not runtime.platform.isWindows():
args.append('--pidfile=%s' % (self.pidPath,))
args.extend(['-noy',
self.tacPath])
if setsid:
args = ['setsid'] + args
executable = setsid[0]
self.process = process.spawnProcess(
self.connector, executable, tuple(args), env=env)
class stopped(modal.mode):
def getProcess(self):
self.mode = 'starting'
self.waitingForProcess = []
self._startProcess()
# Mode has changed, this will call some other
# implementation of getProcess.
return self.getProcess()
def stopProcess(self):
return defer.succeed(None)
class starting(modal.mode):
def getProcess(self):
d = defer.Deferred()
self.waitingForProcess.append(d)
return d
def stopProcess(self):
def eb(err):
err.trap(ProcessUnavailable)
d = defer.Deferred().addErrback(eb)
self.waitingForProcess.append(d)
self.mode = 'waiting_ready'
return d
def childProcessCreated(self):
self.mode = 'ready'
if self.onProcessStartup is not None:
self.onProcessStartup()
for d in self.waitingForProcess:
d.callback(self.juice)
del self.waitingForProcess
def childProcessTerminated(self, reason):
_childProcTerminated(self, reason)
if self.onProcessTermination is not None:
self.onProcessTermination()
class ready(modal.mode):
def getProcess(self):
return defer.succeed(self.juice)
def stopProcess(self):
self.mode = 'stopping'
self.onShutdown = defer.Deferred()
Shutdown().do(self.juice)
return self.onShutdown
def childProcessTerminated(self, reason):
self.mode = 'stopped'
self.process = self.connector = None
if self.onProcessTermination is not None:
self.onProcessTermination()
class stopping(modal.mode):
def getProcess(self):
return defer.fail(ProcessUnavailable("Shutting down"))
def stopProcess(self):
return self.onShutdown
def childProcessTerminated(self, reason):
self.mode = 'stopped'
self.process = self.connector = None
self.onShutdown.callback(None)
class waiting_ready(modal.mode):
def getProcess(self):
return defer.fail(ProcessUnavailable("Shutting down"))
def childProcessCreated(self):
# This will put us into the stopped state - no big deal,
# we are going into the ready state as soon as it returns.
_childProcTerminated(self, RuntimeError("Shutting down"))
# Dip into the ready mode for ever so brief an instant so
# that we can shut ourselves down.
self.mode = 'ready'
return self.stopProcess()
def childProcessTerminated(self, reason):
_childProcTerminated(self, reason)
if self.onProcessTermination is not None:
self.onProcessTermination()
class JuiceConnector(protocol.ProcessProtocol):
def __init__(self, proto, controller):
self.juice = proto
self.controller = controller
def connectionMade(self):
log.msg("Subprocess started.")
self.juice.makeConnection(self)
self.controller.childProcessCreated()
# Transport
disconnecting = False
def write(self, data):
self.transport.write(data)
def writeSequence(self, data):
self.transport.writeSequence(data)
def loseConnection(self):
self.transport.loseConnection()
def getPeer(self):
return ('omfg what are you talking about',)
def getHost(self):
return ('seriously it is a process this makes no sense',)
def inConnectionLost(self):
log.msg("Standard in closed")
protocol.ProcessProtocol.inConnectionLost(self)
def outConnectionLost(self):
log.msg("Standard out closed")
protocol.ProcessProtocol.outConnectionLost(self)
def errConnectionLost(self):
log.msg("Standard err closed")
protocol.ProcessProtocol.errConnectionLost(self)
def outReceived(self, data):
self.juice.dataReceived(data)
def errReceived(self, data):
log.msg("Received stderr from subprocess: " + repr(data))
def processEnded(self, status):
log.msg("Process ended")
self.juice.connectionLost(status)
self.controller.childProcessTerminated(status)
class JuiceChild(juice.Juice):
"""
Protocol class which runs in the child process
This just defines one behavior on top of a regular juice protocol: the
shutdown command, which drops the connection and stops the reactor.
"""
shutdown = False
def connectionLost(self, reason):
juice.Juice.connectionLost(self, reason)
if self.shutdown:
reactor.stop()
def command_SHUTDOWN(self):
log.msg("Shutdown message received, goodbye.")
self.shutdown = True
return {}
command_SHUTDOWN.command = Shutdown
class SetStore(juice.Command):
"""
Specify the location of the site store.
"""
commandName = 'Set-Store'
arguments = [('storepath', juice.Path())]
class SuspendProcessor(juice.Command):
"""
Prevent a particular reliable listener from receiving any notifications
until a L{ResumeProcessor} command is sent or the batch process is
restarted.
"""
commandName = 'Suspend-Processor'
arguments = [('storepath', juice.Path()),
('storeid', juice.Integer())]
class ResumeProcessor(juice.Command):
"""
Cause a particular reliable listener to begin receiving notifications
again.
"""
commandName = 'Resume-Processor'
arguments = [('storepath', juice.Path()),
('storeid', juice.Integer())]
class CallItemMethod(juice.Command):
"""
Invoke a particular method of a particular item.
"""
commandName = 'Call-Item-Method'
arguments = [('storepath', juice.Path()),
('storeid', juice.Integer()),
('method', juice.String())]
class BatchProcessingControllerService(service.Service):
"""
Controls starting, stopping, and passing messages to the system process in
charge of remote batch processing.
"""
def __init__(self, store):
self.store = store
self.setName("Batch Processing Controller")
def startService(self):
service.Service.startService(self)
tacPath = util.sibpath(__file__, "batch.tac")
proto = BatchProcessingProtocol()
rundir = self.store.dbdir.child("run")
logdir = rundir.child("logs")
for d in rundir, logdir:
try:
d.createDirectory()
except OSError:
pass
self.batchController = ProcessController(
"batch", proto, tacPath,
self._setStore, self._restartProcess,
logdir.child("batch.log").path,
rundir.child("batch.pid").path)
def _setStore(self):
return SetStore(storepath=self.store.dbdir).do(self.batchController.juice)
def _restartProcess(self):
reactor.callLater(1.0, self.batchController.getProcess)
def stopService(self):
service.Service.stopService(self)
d = self.batchController.stopProcess()
d.addErrback(lambda err: err.trap(error.ProcessDone))
return d
def call(self, itemMethod):
"""
Invoke the given bound item method in the batch process.
Return a Deferred which fires when the method has been invoked.
"""
item = itemMethod.im_self
method = itemMethod.im_func.func_name
return self.batchController.getProcess().addCallback(
CallItemMethod(storepath=item.store.dbdir,
storeid=item.storeID,
method=method).do)
def suspend(self, storepath, storeID):
return self.batchController.getProcess().addCallback(
SuspendProcessor(storepath=storepath, storeid=storeID).do)
def resume(self, storepath, storeID):
return self.batchController.getProcess().addCallback(
ResumeProcessor(storepath=storepath, storeid=storeID).do)
class _SubStoreBatchChannel(object):
"""
SubStore adapter for passing messages to the batch processing system
process.
SubStores are adaptable to L{iaxiom.IBatchService} via this adapter.
"""
implements(iaxiom.IBatchService)
def __init__(self, substore):
self.storepath = substore.dbdir
self.service = iaxiom.IBatchService(substore.parent)
def call(self, itemMethod):
return self.service.call(itemMethod)
def suspend(self, storeID):
return self.service.suspend(self.storepath, storeID)
def resume(self, storeID):
return self.service.resume(self.storepath, storeID)
def storeBatchServiceSpecialCase(st, pups):
if st.parent is not None:
return _SubStoreBatchChannel(st)
return service.IService(st).getServiceNamed("Batch Processing Controller")
class BatchProcessingProtocol(JuiceChild):
siteStore = None
def __init__(self, service=None, issueGreeting=False):
juice.Juice.__init__(self, issueGreeting)
self.storepaths = []
if service is not None:
service.cooperator = cooperator.Cooperator()
self.service = service
def connectionLost(self, reason):
# In the child process, we are a server. In the child process, we
# don't want to keep running after we can't talk to the client anymore.
if self.isServer:
reactor.stop()
def command_SET_STORE(self, storepath):
from axiom import store
assert self.siteStore is None
self.siteStore = store.Store(storepath, debug=False)
self.subStores = {}
self.pollCall = task.LoopingCall(self._pollSubStores)
self.pollCall.start(10.0)
return {}
command_SET_STORE.command = SetStore
def command_SUSPEND_PROCESSOR(self, storepath, storeid):
return self.subStores[storepath.path].suspend(storeid).addCallback(lambda ign: {})
command_SUSPEND_PROCESSOR.command = SuspendProcessor
def command_RESUME_PROCESSOR(self, storepath, storeid):
return self.subStores[storepath.path].resume(storeid).addCallback(lambda ign: {})
command_RESUME_PROCESSOR.command = ResumeProcessor
def command_CALL_ITEM_METHOD(self, storepath, storeid, method):
return self.subStores[storepath.path].call(storeid, method).addCallback(lambda ign: {})
command_CALL_ITEM_METHOD.command = CallItemMethod
def _pollSubStores(self):
from axiom import store, substore
# Any service which has encountered an error will have logged it and
# then stopped. Prune those here, so that they are noticed as missing
# below and re-added.
for path, svc in self.subStores.items():
if not svc.running:
del self.subStores[path]
try:
paths = set([p.path for p in self.siteStore.query(substore.SubStore).getColumn("storepath")])
except eaxiom.SQLError, e:
# Generally, database is locked.
log.msg("SubStore query failed with SQLError: %r" % (e,))
except:
# WTF?
log.msg("SubStore query failed with bad error:")
log.err()
else:
for removed in set(self.subStores) - paths:
self.subStores[removed].disownServiceParent()
del self.subStores[removed]
if VERBOSE:
log.msg("Removed SubStore " + removed)
for added in paths - set(self.subStores):
try:
s = store.Store(added, debug=False)
except eaxiom.SQLError, e:
# Generally, database is locked.
log.msg("Opening sub-Store failed with SQLError: %r" % (e,))
except:
log.msg("Opening sub-Store failed with bad error:")
log.err()
else:
self.subStores[added] = BatchProcessingService(s, style=iaxiom.REMOTE)
self.subStores[added].setServiceParent(self.service)
if VERBOSE:
log.msg("Added SubStore " + added)
class BatchProcessingService(service.Service):
"""
Steps over the L{iaxiom.IBatchProcessor} powerups for a single L{axiom.store.Store}.
"""
def __init__(self, store, style=iaxiom.LOCAL):
self.store = store
self.style = style
self.suspended = []
def suspend(self, storeID):
item = self.store.getItemByID(storeID)
self.suspended.append(item)
return item.suspend()
def resume(self, storeID):
item = self.store.getItemByID(storeID)
self.suspended.remove(item)
return item.resume()
def call(self, storeID, methodName):
return defer.maybeDeferred(getattr(self.store.getItemByID(storeID), methodName))
def items(self):
return self.store.powerupsFor(iaxiom.IBatchProcessor)
def processWhileRunning(self):
"""
Run tasks until stopService is called.
"""
work = self.step()
for result, more in work:
yield result
if not self.running:
break
if more:
delay = 0.1
else:
delay = 10.0
yield task.deferLater(reactor, delay, lambda: None)
def step(self):
while True:
items = list(self.items())
if VERBOSE:
log.msg("Found %d processors for %s" % (len(items), self.store))
ran = False
more = False
while items:
ran = True
item = items.pop()
if VERBOSE:
log.msg("Stepping processor %r (suspended is %r)" % (item, self.suspended))
try:
itemHasMore = item.store.transact(item.step, style=self.style, skip=self.suspended)
except _ProcessingFailure, e:
log.msg("%r failed while processing %r:" % (e.reliableListener, e.workUnit))
log.err(e.failure)
e.mark()
# _Fuck_. /Fuck/. If user-code in or below (*fuck*)
# item.step creates a Failure on any future iteration
# (-Fuck-) of this loop, it will get a reference to this
# exception instance, since it's in locals and Failures
# extract and save locals (Aaarrrrggg). Get rid of this so
# that doesn't happen. See also the definition of
# _ProcessingFailure.__init__.
e = None
else:
if itemHasMore:
more = True
yield None, bool(more or items)
if not ran:
yield None, more
def startService(self):
service.Service.startService(self)
self.parent.cooperator.coiterate(self.processWhileRunning())
def stopService(self):
service.Service.stopService(self)
self.store.close()
class BatchManholePowerup(item.Item):
"""
Previously, an L{IConchUser} powerup. This class is only still defined for
schema compatibility. Any instances of it will be deleted by an upgrader.
See #1001.
"""
schemaVersion = 2
unused = attributes.integer(
doc="Satisfy Axiom requirement for at least one attribute")
registerDeletionUpgrader(BatchManholePowerup, 1, 2)
|