task.task.Task Class Reference

Provides a quick way to execute long running procedures. More...

Public Member Functions
	__new__ (Type cls, Callable fn, *args, **kwargs)
	Method that indicates how a new object for this class is created.
	__init__ (self, Callable fn, *args, **kwargs)
	Initializes a new Task, saving within its attributes the arguments passed.
	set_thread_pool (self, QThreadPool tp)
	Sets a custom QThreadPool in which the Task will be executed.
QThreadPool	get_thread_pool (self)
	Gets the currently used QThreadPool.
int	start (self, bool with_qrunnable=True)
	Starts the task, by requesting a common QThreadPool the execution of this object (which it accepts, as it is a QRunnable).
	run (self)
	Method that contains the logic that is pushed to the secondary thread.

Detailed Description

Provides a quick way to execute long running procedures.

Attention

To use this class, please import with the following statement:

from elt.cut.task.task import Task

Provides a quick way to execute long running procedures in a separate thread. If the user may choose, they can set up connections to signals that are triggered in specific circumstances.

Inherits from QRunnable to handle task setup and wrap-up. Since QRunnable is not a QObject, it cannot have signals and slot: Thus, this is delegated to a WorkerSignals class that is owned by the WorkerIO.

In this example, it is shown how to use this class::

from elt.cut.task.task import Task
task = Task(function_to_execute)
task.signals.result.connect(function_to_publish_result)
task.signals.finished.connect(function_when_finished)
task.start()

The start() method requests a common QThreadPool to execute this object.

Note

This class is intended to simplify threading, and is in no way a complete replacement for all situations.

Copyright

ESO - European Southern Observatory

Encapsulates a task to be executed, and executes it in another thread.

Constructor & Destructor Documentation

__init__()

task.task.Task.__init__	(		self,
		Callable	fn,
		*	args,
		**	kwargs )

Initializes a new Task, saving within its attributes the arguments passed.

Parameters

[in]	fn	The function callback to run on this worker thread. Supplied args and kwargs will be passed through to the runner.
[in]	args	Arguments to pass to the callback function
[in]	kwargs	Keywords to pass to the callback function

Member Function Documentation

__new__()

task.task.Task.__new__	(	Type	cls,
		Callable	fn,
		*	args,
		**	kwargs )

Method that indicates how a new object for this class is created.

Implements singleton pattern for the ThreadPool. The first object created will store a "static" reference of the same object, and from then on the "static" reference is returned.

get_thread_pool()

QThreadPool task.task.Task.get_thread_pool

(

self

)

Gets the currently used QThreadPool.

Returns

QThreadPool The thread pool currently used by the task.

run()

task.task.Task.run

(

self

)

Method that contains the logic that is pushed to the secondary thread.

This executes the method fn, with arguments args and kwargs, as indicated during initialization.

set_thread_pool()

task.task.Task.set_thread_pool	(		self,
		QThreadPool	tp )

Sets a custom QThreadPool in which the Task will be executed.

Developer is responsible for its lifecycle.

start()

int task.task.Task.start	(		self,
		bool	with_qrunnable = True )

Starts the task, by requesting a common QThreadPool the execution of this object (which it accepts, as it is a QRunnable).

If no threads are available, the task will be queued for execution.

Parameters

[in]

with_qrunnable

Uses QRunnable instead of taurus.Manager for task job execution. In particular, QRunnables offer more feedback capabilities.

Returns

Task id as an int.

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The documentation for this class was generated from the following file:

• task/src/elt/cut/task/task.py