def __init__(self):
self.threads = {} # { thread number -> 1 }
self.queue = Queue()
self.thread_mgmt_lock = thread.allocate_lock()
def __init__(self):
self.threads = {} # { thread number -> 1 }
self.queue = Queue()
self.thread_mgmt_lock = threading.Lock()
class ThreadedTaskDispatcher(object):
"""A Task Dispatcher that creates a thread for each task.
"""
stop_count = 0 # Number of threads that will stop soon.
start_new_thread = thread.start_new_thread
logger = logger
def __init__(self):
self.threads = {} # { thread number -> 1 }
self.queue = Queue()
self.thread_mgmt_lock = thread.allocate_lock()
def handler_thread(self, thread_no):
threads = self.threads
try:
while threads.get(thread_no):
task = self.queue.get()
if task is None:
# Special value: kill this thread.
break
try:
task.service()
except Exception as e:
self.logger.exception(
'Exception when servicing %r' % task)
if isinstance(e, JustTesting):
break
finally:
mlock = self.thread_mgmt_lock
mlock.acquire()
try:
self.stop_count -= 1
threads.pop(thread_no, None)
finally:
mlock.release()
def set_thread_count(self, count):
mlock = self.thread_mgmt_lock
mlock.acquire()
try:
threads = self.threads
thread_no = 0
running = len(threads) - self.stop_count
while running < count:
# Start threads.
while thread_no in threads:
thread_no = thread_no + 1
threads[thread_no] = 1
running += 1
self.start_new_thread(self.handler_thread, (thread_no,))
thread_no = thread_no + 1
if running > count:
# Stop threads.
to_stop = running - count
self.stop_count += to_stop
for n in range(to_stop):
self.queue.put(None)
running -= 1
finally:
mlock.release()
def add_task(self, task):
try:
task.defer()
self.queue.put(task)
except:
task.cancel()
raise
def shutdown(self, cancel_pending=True, timeout=5):
self.set_thread_count(0)
# Ensure the threads shut down.
threads = self.threads
expiration = time.time() + timeout
while threads:
if time.time() >= expiration:
self.logger.warning(
"%d thread(s) still running" %
len(threads))
break
time.sleep(0.1)
if cancel_pending:
# Cancel remaining tasks.
try:
queue = self.queue
while not queue.empty():
task = queue.get()
if task is not None:
task.cancel()
except Empty: # pragma: no cover
pass
return True
return False
class ThreadedTaskDispatcher(object):
"""A Task Dispatcher that creates a thread for each task.
"""
stop_count = 0 # Number of threads that will stop soon.
logger = logger
def __init__(self):
self.threads = {} # { thread number -> 1 }
self.queue = Queue()
self.thread_mgmt_lock = threading.Lock()
def start_new_thread(self, target, args):
t = threading.Thread(target=target, name='waitress', args=args)
t.daemon = True
t.start()
def handler_thread(self, thread_no):
threads = self.threads
try:
while threads.get(thread_no):
task = self.queue.get()
if task is None:
# Special value: kill this thread.
break
try:
task.service()
except Exception as e:
self.logger.exception('Exception when servicing %r' % task)
if isinstance(e, JustTesting):
break
finally:
with self.thread_mgmt_lock:
self.stop_count -= 1
threads.pop(thread_no, None)
def set_thread_count(self, count):
with self.thread_mgmt_lock:
threads = self.threads
thread_no = 0
running = len(threads) - self.stop_count
while running < count:
# Start threads.
while thread_no in threads:
thread_no = thread_no + 1
threads[thread_no] = 1
running += 1
self.start_new_thread(self.handler_thread, (thread_no, ))
thread_no = thread_no + 1
if running > count:
# Stop threads.
to_stop = running - count
self.stop_count += to_stop
for n in range(to_stop):
self.queue.put(None)
running -= 1
def add_task(self, task):
try:
task.defer()
self.queue.put(task)
except:
task.cancel()
raise
def shutdown(self, cancel_pending=True, timeout=5):
self.set_thread_count(0)
# Ensure the threads shut down.
threads = self.threads
expiration = time.time() + timeout
while threads:
if time.time() >= expiration:
self.logger.warning("%d thread(s) still running" %
len(threads))
break
time.sleep(0.1)
if cancel_pending:
# Cancel remaining tasks.
try:
queue = self.queue
while not queue.empty():
task = queue.get()
if task is not None:
task.cancel()
except Empty: # pragma: no cover
pass
return True
return False
