def connect(self):
"""\
Try to connect to this node's remote side.
"""
assert self.node_id is not None
if self._server:
return # already done
if self._connector: # in progress: wait for it
trace("remote", "Chain connect to node %d", self.node_id)
yield triggeredDefer(self._connector)
return
if self.node_id not in self.fs.topology:
trace("remote", "Not connecting to node %d: no topo", self.node_id)
return
if self.fs.topology[self.node_id] != self.node_id:
trace("remote", "Not connecting to node %d: via %s", self.node_id, self.fs.topology[self.node_id])
return
trace("remote", "Connecting to node %d", self.node_id)
try:
with self.fs.db() as db:
try:
m, = yield db.DoFn(
"select method from updater where src=${src} and dest=${dest}",
src=self.fs.node_id,
dest=self.node_id,
)
except NoData:
raise NoLink(self.node_id, "No Data")
m = __import__("sqlfuse.connect." + m, fromlist=("NodeClient",))
m = m.NodeClient(self)
self._connector = m.connect()
# Do this to avoid having a single Deferred both in the inline
# callback chain and as a possible cancellation point
yield triggeredDefer(self._connector)
if self._server is None:
raise NoLink(self.node_id, "No _server")
except NoLink:
raise
except Exception as e: # no connection
if isinstance(e, (err.ConnectionRefusedError, NoConnection)):
trace("remote", "No link to %d, retrying", self.node_id)
else:
f = failure.Failure()
log.err(f, "Connecting remote")
self.queue_retry()
finally:
self._connector = None
def stopService(self):
"""Shutdown. Part of IService. Triggers a last run of the worker."""
trace('background',"StopService %s",self.__class__.__name__)
try:
self.do_idle = True
super(BackgroundJob,self).stopService()
if self.workerCall:
self.workerCall.cancel()
self.workerCall = None
IdleWorker.add(self)
d = triggeredDefer(self.workerDefer)
if d is None:
trace('background',"StopService %s: not running",self.__class__.__name__)
else:
trace('background',"StopService %s: wait for finish",self.__class__.__name__)
def rep(r):
trace('background',"StopService %s: finished",self.__class__.__name__)
return r
d.addBoth(rep)
return d
except Exception as e:
log.err(e,"StopService "+self.__class__.__name__)