twisted.internet.task.LoopingCall
class documentationtwisted.internet.task
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Call a function repeatedly.
If f
returns a deferred, rescheduling will not take place
until the deferred has fired. The result value is ignored.
Instance Variable | f | The function to call. |
Instance Variable | a | A tuple of arguments to pass the function. |
Instance Variable | kw | A dictionary of keyword arguments to pass to the function. |
Instance Variable | clock | A provider of twisted.internet.interfaces.IReactorTime .
The default is twisted.internet.reactor .
Feel free to set this to something else, but it probably ought to be set
*before* calling start . |
Instance Variable | running | A flag which is True while f is scheduled to be
called (or is currently being called). It is set to True when
start
is called and set to False when stop is
called or if f raises an exception. In either case, it will be
False by the time the Deferred returned by start
fires its callback or errback. (type: bool ) |
Method | __init__ | Undocumented |
Method | deferred | DEPRECATED. Deferred fired
when loop stops or fails. |
Class Method | withCount | An alternate constructor for LoopingCall
that makes available the number of calls which should have occurred since
it was last invoked. |
Method | start | Start running function every interval seconds. |
Method | stop | Stop running function. |
Method | reset | Skip the next iteration and reset the timer. |
Method | __call__ | Undocumented |
Method | __repr__ | Undocumented |
Instance Variable | _realLastTime | When counting skips, the time at which the skip counter was last invoked. (type: float ) |
Instance Variable | _runAtStart | A flag indicating whether the 'now' argument was passed to LoopingCall.start . (type: bool ) |
Method | _intervalOf | Determine the number of intervals passed as of the given point in time. |
Method | _scheduleFrom | Schedule the next iteration of this looping call. |
twisted.internet.interfaces.IReactorTime
.
The default is twisted.internet.reactor
.
Feel free to set this to something else, but it probably ought to be set
*before* calling start
.
True
while f
is scheduled to be
called (or is currently being called). It is set to True
when
start
is called and set to False
when stop
is
called or if f
raises an exception. In either case, it will be
False
by the time the Deferred
returned by start
fires its callback or errback. (type: bool
)
float
)
LoopingCall.start
. (type: bool
)
DEPRECATED. Deferred
fired
when loop stops or fails.
Use the Deferred
returned by LoopingCall.start
.
An alternate constructor for LoopingCall
that makes available the number of calls which should have occurred since
it was last invoked.
Note that this number is an int
value; It represents the
discrete number of calls that should have been made. For example, if you
are using a looping call to display an animation with discrete frames, this
number would be the number of frames to advance.
The count is normally 1, but can be higher. For example, if the reactor
is blocked and takes too long to invoke the LoopingCall
,
a Deferred returned from a previous call is not fired before an interval
has elapsed, or if the callable itself blocks for longer than an interval,
preventing itself from being called.
When running with an interval if 0, count will be always 1.
Parameters | countCallable | A callable that will be invoked each time the resulting LoopingCall is run,
with an integer specifying the number of calls that should have been
invoked. (type: 1-argument callable which takes an int ) |
Returns | An instance of LoopingCall
with call counting enabled, which provides the count as the first
positional argument. (type: LoopingCall ) | |
Present Since | 9.0 |
Determine the number of intervals passed as of the given point in time.
Parameters | t | The specified time (from the start of the LoopingCall )
to be measured in intervals |
Returns | The int number of intervals which have passed as of the given
point in time. |
Start running function every interval seconds.
Parameters | interval | The number of seconds between calls. May be less than one. Precision will depend on the underlying platform, the available hardware, and the load on the system. |
now | If True, run this call right now. Otherwise, wait until the interval has elapsed before beginning. | |
Returns | A Deferred whose callback will be invoked with self when
self.stop is called, or whose errback will be invoked when the
function raises an exception or returned a deferred that has its errback
invoked. |
Schedule the next iteration of this looping call.
Parameters | when | The present time from whence the call is scheduled. |