twisted.internet.defer.DeferredQueue(object)
class documentationtwisted.internet.defer
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An event driven queue.
Objects may be added as usual to this queue. When an attempt is made to
retrieve an object when the queue is empty, a Deferred
is
returned which will fire when an object becomes available.
Instance Variable | size | The maximum number of objects to allow into the queue at a time. When an
attempt to add a new object would exceed this limit, QueueOverflow
is raised synchronously. None
for no limit. |
Instance Variable | backlog | The maximum number of Deferred gets
to allow at one time. When an attempt is made to get an object which would
exceed this limit, QueueUnderflow
is raised synchronously. None
for no limit. |
Method | __init__ | Undocumented |
Method | put | Add an object to this queue. |
Method | get | Attempt to retrieve and remove an object from the queue. |
Method | _cancelGet | Remove a deferred d from our waiting list, as the deferred has been canceled. |
QueueOverflow
is raised synchronously. None
for no limit.
Deferred
gets
to allow at one time. When an attempt is made to get an object which would
exceed this limit, QueueUnderflow
is raised synchronously. None
for no limit.
Remove a deferred d from our waiting list, as the deferred has been canceled.
Note: We do not need to wrap this in a try/except to catch d not being in self.waiting because this canceller will not be called if d has fired. put() pops a deferred out of self.waiting and calls it, so the canceller will no longer be called.
Parameters | d | The deferred that has been canceled. |
Add an object to this queue.
Raises | QueueOverflow | Too many objects are in this queue. |