cs.threads 20190812

threading and communication/synchronisation conveniences

Release 20190812: bg: compute default name before wrapping func in @logexc.

Thread related convenience classes and functions.

Class AdjustableSemaphore

A semaphore whose value may be tuned after instantiation.

Function bg(func, daemon=None, name=None, no_start=False, no_logexc=False)

Dispatch the callable func in its own Thread; return the Thread.

Parameters:

• func: callable to run in its own Thread.
• daemon: optional argument specifying the .daemon attribute.
• name: optional argument specifying the Thread name.
• no_start: optional argument, default False. If true, do not start the Thread.
• no_logexc: if false (default False), wrap func in @logexc.

Class LockableMixin

Trite mixin to control access to an object via its ._lock attribute. Exposes the ._lock as the property .lock. Presents a context manager interface for obtaining an object's lock.

Function locked(func)

A decorator for monitor functions that must run within a lock. Relies upon a ._lock attribute for locking.

Function locked_property(func, lock_name='_lock', prop_name=None, unset_object=None)

A thread safe property whose value is cached. The lock is taken if the value needs to computed.

Function via(cmanager, func, *a, **kw)

Return a callable that calls the supplied func inside a with statement using the context manager cmanager. This intended use case is aimed at deferred function calls.

Class WorkerThreadPool

MRO: cs.resources.MultiOpenMixin, cs.obj.O
A pool of worker threads to run functions.

Method WorkerThreadPool.__init__(self, name=None, max_spare=4)

Initialise the WorkerThreadPool.

Paramaters: name: optional name for the pool max_spare: maximum size of each idle pool (daemon and non-daemon)

Class WTPoolEntry

MRO: builtins.tuple
WTPoolEntry(thread, queue)

Release Log

Release 20190812: bg: compute default name before wrapping func in @logexc.

Release 20190729: bg: provide default name, run callable inside Pfx, add optional no_logexc=False param preventing @logec wrapper if true.

Release 20190422: bg(): new optional no_start=False keyword argument, preventing Thread.start if true

Release 20190102: Drop some unused classes. New LockableMixin, presenting a context manager and a .lock property.

Release 20160828: Use "install_requires" instead of "requires" in DISTINFO.

Release 20160827: Replace bare "excepts" with "except BaseException". Doc updates. Other minor improvements.

Release 20150115: First PyPI release.