A threading library written in python. Help you build threaded app.
This module was originally included in ComicCrawler.
- Pause, resume, stop, and restart a thread.
- Support child threads.
- Easily run asynchronous task across multiple threads.
- Communicate between threads with events.
- Use channel to broadcast events.
pip install pythreadworker
Basic operations and event:
#! python3
# Always use worker.sleep. pyWorker would process event queue during
# waiting.
from worker import create_worker, listen, sleep
@create_worker
def increaser():
count = 1
@listen("SET_VALUE")
def _(event):
nonlocal count
# you don't need a lock to manipulate `count`
count = event.data
while True:
print(count)
# because the listener and the while loop are in the same thread
count += 1
sleep(1)
while True:
command = input("input command: ")
if command == "start":
increaser.start()
elif command == "stop":
increaser.stop()
elif command == "pause":
increaser.pause()
elif command == "resume":
increaser.resume()
elif command.startswith("set"):
increaser.fire("SET_VALUE", int(command[4:]))
elif command == "exit":
increaser.stop()
break
Async task:
#! python3
from worker import aynsc_, sleep
def long_work(t):
sleep(t)
return "Finished in {} second(s)".format(t)
# The async task will be executed in another thread.
pending = async_(long_work, 5)
# Do other stuff here...
# Wait the thread to complete and get the result. If the task is already
# finished, it returns directly with the result.
print(pending.get())
Use Channel to broadcast events:
#! python3
from worker import Worker, Channel
channel = Channel()
def create_printer(name):
printer = Worker()
@printer.listen("PRINT")
def _(event):
print(name, "recieved", event.data)
channel.sub(printer)
printer.start()
return printer
foo = create_printer("foo")
bar = create_printer("bar")
channel.pub("PRINT", "Hello channel!")
foo.stop()
bar.stop()
Child thread and event bubbling/broadcasting:
#! python3
from worker import Worker, sleep
def create_thread(name, parent):
thread = Worker(parent=parent)
@thread.listen("HELLO")
def _(event):
print(name)
return thread.start()
parent = create_thread("parent", None)
child = create_thread("child", parent)
grand = create_thread("grand", child)
# broadcast/bubble is happened in main thread. It doesn't gaurantee the
# execution order of listeners.
parent.fire("HELLO", broadcast=True)
sleep(1)
grand.fire("HELLO", bubble=True)
sleep(1)
# stop a parent thread would also stop its children
parent.stop()
The module creates a event queue for each thread, including the main thread. When blocking functions are called (worker.sleep
, worker.wait_event
, worker.Async.get
, etc), they enter the event loop so the thread can process events, communicate with other threads, or raise an exception during the call.
Which also means that if you don't use functions provided by pyThreadWorker, the module has no chance to affect your existing code. It should be easy to work with other frameworks.
http://pythreadworker.readthedocs.io/en/latest/
- Thread safe operations: http://effbot.org/pyfaq/what-kinds-of-global-value-mutation-are-thread-safe.htm
- 0.10.0 (Apr 19, 2022)
- Change: require python 3.10+.
- Change: now calling
wait_*
functions would initiate a root worker if there is no worker on the current thread.
- 0.9.0 (Jun 8, 2018)
- Change: The signature of `later()` is changed. You should use it to schedule a task on the specific thread.
- Change: The listener registered by `listener()` shortcut would be removed once the thread is stopped.
- Add:
permanent
andonce
arguments toListener
. - Add:
Defer
. A util to handle cross thread communication.
- 0.8.0 (Mar 26, 2017)
- Add print_traceback option to Worker.
- Ability to use
later
as decorator. - Drop __all__ in __init__.py.
- function rename: async -> async_, sync -> await_.
- Async now extends Worker and needs start() to run.
- later() now doesn't use current thread as target by default. To use current thread as target, pass target=True.
- Various function are able to used as decorator, including
await_, async_, later
. - Drop daemon Thread, use daemon Worker.
- Add
Worker.wait_until
. - Add
create_worker
. - Refactor.
- 0.7.0 (Feb 26, 2017)
- Improve docs.
- Drop
def target(thread)
syntax, usecurrent()
to get current thread instead. - Use pylint and sphinx.
- Export more shortcuts.
- 0.6.0 (Jul 1, 2016)
- Add
thread.later
.
- Add
- 0.5.1 (Apr 22, 2016)
- Use float in sleep function.
- 0.5.0 (Apr 22, 2016)
- Add sync.
- 0.4.0 (Apr 20, 2016) breaking change
- Interface completely changed
- Drop
Message.put, .get
- Drop
UserWorker
- Drop
Worker.create_child
. Useparent
option in constructor instead. - Drop
global_cleanup
- Add
sleep
- Add
current
- Add
Channel
- Add
Listener.priority
- Add
daemon
option toWorker
Worker.cleanup
-->Worker.update
Worker.message
-->Worker.fire
Worker.wait_message
-->Worker.wait_event
Worker.message_loop
-->Worker.wait_forever
- 0.3.0 (Jun 14, 2015)
- Catch BaseException.