traits_futures.traits_executor module

Executor to submit background tasks.

traits_futures.traits_executor.ExecutorState = Enum(RUNNING, STOPPING, STOPPED)

Trait type representing the executor state.

traits_futures.traits_executor.RUNNING = 'running'

Executor is currently running (this is the initial state).

traits_futures.traits_executor.STOPPED = 'stopped'

Executor is stopped.

traits_futures.traits_executor.STOPPING = 'stopping'

Executor has been requested to stop. In this state, no new jobs can be submitted, and we’re waiting for old ones to complete.

class traits_futures.traits_executor.TraitsExecutor(thread_pool=None, *, worker_pool=None, max_workers=None, context=None, **traits)

Bases: traits.has_traits.HasStrictTraits

Executor to initiate and manage background tasks.

Parameters

• thread_pool (concurrent.futures.Executor, optional) –

  Deprecated alias for worker_pool.

  Deprecated since version 0.2: Use worker_pool instead.

• worker_pool (concurrent.futures.Executor, optional) – If supplied, provides the underlying worker pool executor to use. In this case, the creator of the TraitsExecutor is responsible for shutting down the worker pool once it’s no longer needed. If not supplied, a new private worker pool will be created, and this object’s stop method will shut down that worker pool.

• max_workers (int or None, optional) – Maximum number of workers for the private worker pool. This parameter is mutually exclusive with worker_pool. The default is None, which delegates the choice of number of workers to Python’s concurrent.futures module.

• context (IParallelContext, optional) – Parallelism context, providing appropriate concurrent primitives and worker pools for a given choice of parallelism (for example multithreading or multiprocessing). If not given, assumes multithreading. Note that if both context and worker_pool are given, they must be compatible.

running = Property(Bool())

Derived state: true if this executor is running; False if it’s stopped or stopping.

state = ExecutorState

Current state of this executor.

stop()

Initiate stop: cancel existing jobs and prevent new ones.

stopped = Property(Bool())

Derived state: true if this executor is stopped and it’s safe to dispose of related resources (like the worker pool).

submit(task)

Submit a task to the executor, and return the corresponding future.

Parameters

task (ITaskSpecification) –

Returns

future – Future for this task.

Return type

IFuture

submit_call(callable, *args, **kwargs)

Convenience function to submit a background call.

Deprecated since version 0.2: Use the submit_call function instead.

Parameters

• callable (an arbitrary callable) – Function to execute in the background.

• *args – Positional arguments to pass to that function.

• **kwargs – Named arguments to pass to that function.

Returns

future – Object representing the state of the background call.

Return type

CallFuture

submit_iteration(callable, *args, **kwargs)

Convenience function to submit a background iteration.

Deprecated since version 0.2: Use the submit_iteration function instead.

Parameters

• callable (an arbitrary callable) – Function executed in the background to provide the iterable.

• *args – Positional arguments to pass to that function.

• **kwargs – Named arguments to pass to that function.

Returns

future – Object representing the state of the background iteration.

Return type

IterationFuture

submit_progress(callable, *args, **kwargs)

Convenience function to submit a background progress call.

Deprecated since version 0.2: Use the submit_progress function instead.

Parameters

• callable (callable accepting a "progress" named argument) – Function executed in the background to provide the iterable. This should accept a “progress” named argument. The callable can then call the “progress” object to report progress.

• *args – Positional arguments to pass to that function.

• **kwargs – Named arguments to pass to that function. These should not include “progress”.

Returns

future – Object representing the state of the background task.

Return type

ProgressFuture