openstack/deb-python-eventlet
Code Issues Proposed changes

fix twistedutil.protocol.ValueQueue in regard to new Queue class

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This commit is contained in:
Denis Bilenko
2009-06-22 15:56:34 +07:00
parent a99f133868
commit 51f9cee438
1 changed files with 7 additions and 12 deletions
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19
eventlet/twistedutil/protocol.py
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@@ -29,10 +29,10 @@ from twisted.python import failure
from eventlet import proc from eventlet import proc
from eventlet.api import getcurrent from eventlet.api import getcurrent
from eventlet.coros import queue, event from eventlet.coros import Queue, event
class ValueQueue(queue): class ValueQueue(Queue):
"""Queue that keeps the last item forever in the queue if it's an exception. """Queue that keeps the last item forever in the queue if it's an exception.
Useful if you send an exception over queue only once, and once sent it must be always Useful if you send an exception over queue only once, and once sent it must be always
available. available.
@@ -40,23 +40,18 @@ class ValueQueue(queue):
def send(self, value=None, exc=None): def send(self, value=None, exc=None):
if exc is not None or not self.has_error(): if exc is not None or not self.has_error():
queue.send(self, value, exc) Queue.send(self, value, exc)
def wait(self): def wait(self):
"""The difference from queue.wait: if there is an only item in the """The difference from Queue.wait: if there is an only item in the
queue and it is an exception, raise it, but keep it in the queue, so Queue and it is an exception, raise it, but keep it in the Queue, so
that future calls to wait() will raise it again. that future calls to wait() will raise it again.
""" """
self.sem.acquire()
if self.has_error() and len(self.items)==1: if self.has_error() and len(self.items)==1:
# the last item, which is an exception, raise without emptying the queue # the last item, which is an exception, raise without emptying the Queue
self.sem.release()
getcurrent().throw(*self.items[0][1]) getcurrent().throw(*self.items[0][1])
else: else:
result, exc = self.items.popleft() return Queue.wait(self)
if exc is not None:
getcurrent().throw(*exc)
return result
def has_error(self): def has_error(self):
return self.items and self.items[-1][1] is not None return self.items and self.items[-1][1] is not None